The Little Picture:
The consumption of carbohydrate during exercise has been shown to be a critical part of maintaining and enhancing performance during intense and prolonged exercise (1, 2, 3, 4).
At the same time, the overconsumption of carbohydrate during exercise has been associated with gastro-intestinal distress (GI-distress), which can be exacerbated by dehydration, heat stress, and highly concentrated carbohydrate sources that empty from the stomach at a faster rate than they can be absorbed by the small intestine (10, 11, 12, 13, 14, 15, 16, 17, 18, 19).
While overconsumption of carbohydrate and under-consumption of fluids is at the heart of GI-distress, a number of factors may help alleviate GI-distress including the use of more than one type of carbohydrate (i.e., glucose & fructose), the addition of fiber like pectin (to help slow the emptying of carbohydrate from the stomach), and the removal of excess food additives (20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30).
We’ve always believed in fresh portables made from scratch to quell GI-distress. But we also recognize, that in the same way we were able to greatly improve the sports drink, there were many opportunities to improve carbohydrate supplements. With that goal in mind, we developed our Fruit Drops - a pectin based energy chew with a specific ratio of glucose and fructose that is flavored only with real fruit and that does not contain the coloring agents, flavoring agents, and waxes common to many similar products.
Made in a convenient bite size drop that contains 4 grams of carbohydrate or 16 Calories per drop, our Fruit Drops are a simple way to regulate carbohydrate consumption during exercise for when we don’t have the time or resources to make fresh food portables from scratch.
Use our Fruit Drops as an easy and convenient source of carbohydrate to help maintain blood sugar and performance during prolonged exercise. As a starting point, for activities lasting longer than 2 hours, consume 1 package of Fruit Drops, containing 160 Calories (40 grams carbohydrate), each hour, beginning the first hour. Realize that the upper limit for carbohydrate absorption and use is about 100 grams per hour (2.5 packages of Fruit Drops). So keep in mind other sources of carbohydrate that you might be consuming like our Exercise Hydration Mix, which contains 80 Calories or 20 grams of carbohydrate per 500 ml serving, to avoid upsetting your gut.
The Big Picture:
Our “Fruit Drops” were made for people who need an easy and convenient source of carbohydrate to fuel their exercise performance. The rationale for their use is based on the simple fact that the consumption of carbohydrate is a critical part of maintaining and enhancing performance during intense and prolonged exercise (1, 2, 3, 4).
While designed for sport and an active lifestyle, it’s not lost upon us that this product is essentially a source of simple sugars and that an excess of sugar is often blamed for obesity and disease (5, 6). While excess of any sort is likely dangerous, it’s important to realize that obesity is a complex and multifactorial issue as are the metabolic diseases associated with it (7). A clear example of this is the fact that artificial sweeteners, which have no calories, are also associated with obesity (8, 9). That all said, we developed our Fruit Drops with physical activity and the problem of maintaining blood sugar during exercise in mind and do not advocate their use outside of the context of athletic performance. Which is to say, use common sense and don’t eat them if you’re just sitting around and don’t need the fuel.
Ironically, for some, the problem of sustaining adequate carbohydrate intake during exercise can result in gastrointestinal distress (GI-distress) in endurance events if too much carbohydrate is consumed at once or at rates that exceed the ability of the small intestine (i.e., gut) to absorb all of the carbohydrate presented to it (10, 11, 12, 13, 14, 15). GI-distress is especially common with hyperosmolar (i.e., a molecular concentration or osmolarity greater than blood) or high calorie liquid and semi-liquid carbohydrate solutions that empty rapidly from the stomach into the gut and can be exacerbated by the use of only a single type of carbohydrate, by food additives not recognized by the gut that increase tonicity (i.e., the number of molecules unable to cross the intestinal wall), and by dehydration or heat stress which can damage the intestinal membrane (12, 16, 17, 18, 19).
While eating too much too fast without enough water under extreme stress is at the heart of GI-distress, there are a few things that may help. For example, adding pectin, a form of fruit fiber, to carbohydrate can slow the rate that carbohydrate empties from the stomach, which may theoretically smooth and temper the load on the gut without significantly affecting carbohydrate absorption or the post-prandial glucose response (20, 21). In addition the use of multiple-transportable carbohydrates in the form of glucose and fructose can improve the absorption of carbohydrate across the gut while reducing the potential for GI-distress (22, 23, 24, 25, 26, 27). Finally, food additives like coloring agents and emulsifiers may harm beneficial intestinal bacteria or microbiota and may negatively affect the intestinal barrier already under stress from the transport of normal foodstuffs like sugar and salt (28, 29, 30). Thus, eliminating ingredients not critical to a carbohydrate supplement may further reduce the stress on the small intestine, not only by reducing the overall osmolarity and tonicity, but by limiting any harmful effect on the intestinal wall.
Although freshly made portables is our preferred solution for maintaining adequate carbohydrate intake during exercise, it was in balancing the need for a convenient and simple fuel for athletic performance with the potential for GI-distress that is common to carbohydrate supplements that our Fruit Drops were developed. Effectively, our Fruit Drops are a pectin based energy chew or gumdrop containing a specific ratio of glucose and fructose, flavored only with real fruit, and without excess ingredients like flavoring agents, coloring agents, perfumes, or waxes common to many energy chews – modifications that attempt to eliminate many of the problems associated with some prepackaged carbohydrate sources.
A single package of Fruit Drops contains 10 drops, at 16 Calories a piece for a total of 160 Calories or 40 grams of carbohydrate per package. With maximal rates of exogenous carbohydrate absorption and oxidation in the range of 70-100 grams per hour (1, 2), a single pack of Fruit Drops along with 1 to 2 servings (500 ml per serving) of our Exercise Hydration Mix (20 grams per serving) each hour, is adequate to meet the upper limit of carbohydrate need in the fittest individuals during the most strenuous exercise.
Still, the intake of carbohydrate during exercise to improve or maintain performance is individual and specific to one’s energy expenditure – something that is highly variable depending upon individual fitness, exercise intensity, the intensity pattern, and exercise duration. Moreover, the maintenance of performance during exercise is not just about adequate carbohydrate ingestion it’s also about adequate hydration and electrolyte replacement (31). While our Fruit Drops can easily provide enough carbohydrate for even the fittest individuals, no modifications, including those made to our Fruit Drops, can prevent GI-distress if carbohydrate is over-consumed, especially without adequate water and sodium. Like all things in the realm of performance and nutrition, it’s up to the individual to determine what works best for them, to use common sense, and to have a well thought out plan for replacing fuel, water, and electrolytes during exercise; which might even mean abstaining from drinking and eating for very short and intense exercise bouts where internal stores are probably more than adequate to meet energy needs and sweat loss.
It’s with this sense of pragmatism that we created our Fruit Drops using the same thinking and process that we used to develop our Exercise Hydration Mix. In the same way that we were never happy with sports drinks until we made our own, we were never satisfied with energy chews until we literally reimagined them from scratch. Although we weren’t sure if we were going to be able to change this category of sports nutrition, we did know that we weren’t going to bring a product to market if we didn’t. It’s for this reason that we truly believe our Fruit Drops change energy chews in the same way our Exercise Hydration Mix changed sports drinks – for the better. Like our drink mixes, our Fruit drops are based on sound science without neglecting taste or real world performance. So for those times when you don’t have enough time to prepare your favorite cookie, rice cake or other real food portable, our Fruit Drops provide a simple and convenient alternative to help fuel your hardest and longest adventures.
When we first created our Exercise Hydration Mix, our goal was to solve the persistent complaint from athletes that sugary sports drinks upset their bellies and left a bad taste in their mouth – complaints that ultimately hampered hydration and hurt performance. To quell complaints and improve performance we began mining the scientific literature, tinkering in our kitchen, and experimenting in the field. This led us to develop a sports drink from scratch with a number of key features: 1) less sugar, 2) a specific ratio of sugars in the form of glucose and fructose, 3) a lighter taste profile created by using real fruit, 4) a profile of electrolytes that better matched what was actually lost in sweat, and the 5) elimination of excess ingredients like coloring agents, emulsifiers, preservatives, and flavoring agents. The result – a very light and clean sports drink with an extremely low molecular concentration or osmolarity (160 mOsmol/L) that transformed how athletes and the industry view hydration.
Our goal in making our “Fruit Drops” was to apply the key lessons we learned when formulating our Exercise Hydration mix to the category of “energy chews and blocks.” To be clear, we were never fans of energy chews for the same reason we were never happy with sports drinks before we made our own. We also didn’t know if it was possible to transform the common energy chew into something we wanted to use ourselves or give to our friends and family. But in the same way we reimagined sports drinks and hydration, we thought it worth a try to reinvent the energy chew. Moreover, we realized the benefit of simplicity and convenience for those needing more carbohydrate than provided by our Exercise Hydration Mix, especially since cooking real food portables from scratch isn't always possible.
To reinvent the energy chew, we took the basic recipe for a gumdrop and made the following modifications:
1. We made our Fruit Drops less sweet by adding slightly more water. This makes our fruit drop softer, less sticky, easier to chew, and more palatable. Gram for gram, this also makes our fruit drop about 15% less sweet or energy dense than competing energy chews. Although this reduces the total calories per bite, it makes eating more fruit drops easier on the palate and gut, which improves one’s ability to stay fueled over the long haul.
2. We made cane sugar the primary ingredient followed by tapioca syrup to get a specific ratio of two sugars – glucose and fructose – that we believe better matches the ratio of fructose and glucose transporters in the small intestine. This allows improved absorption of carbohydrate by taking advantage of the two key sugar transporters in the gut. Our ratio of sugars is significantly different than what is found in competing energy chews – a ratio we put considerable time and effort in developing.
3. Compared to other products we increased the sodium content of our fruit drops to help replace a small portion of the sodium that is lost via sweat. The increased sodium content also has the benefit of satiating the craving for salt that people often get during exercise. Finally, adding sodium along with glucose helps to facilitate the transport of water into the body.
4. Rather than using natural or synthetic flavoring agents we used real fruit for flavor. This gives our Fruit Drops a subtle and light flavor. It tastes like real fruit because it’s made with real fruit.
5. We eliminated a number of ingredients that we consider to be excess that aren’t easily recognized or managed by the body. These ingredients include carnauba wax, coloring agents, additional vitamins, and strong perfumes and flavoring agents.
6. To prevent our Fruit Drops from sticking together we added a sour sugar coating using a combination of apple acid (fumaric acid) and crystalized sugar. Not only does this make each drop easier to handle, it gives our drops a unique and salivating taste. Most importantly, it allowed us to eliminate wax and oils from our fruit drops.
To our delight, the process of tinkering, testing, and trying eventually led to modifications that profoundly changed the taste, feel, and function of our Fruit Drops compared to other energy chews. Admittedly, we didn’t begin with high expectations that the transformation we achieved was even possible. At the same time, we did have extremely high expectations that we weren’t going to put out a product that didn't completely blow us away. The epiphany is that we were all blown away by the end product. We developed something we wanted for ourselves – something we were so happy with that the difficulty and stress of brining something new to market as quickly as possible became moot. Ultimately, we get that there’s a demand for energy chews, but as athletes, coaches, and people our first priority was something better for ourselves and our active friends and family.
Thoughts on Usage:
The use of our Fruit Drops really depends on two things – calories and convenience. Do you actually need the calories? Is your blood sugar low? Are you even hungry? And, most importantly, are you lacking the time and resources to prepare something from scratch?
If the answer to the questions above are yes, then for most people having a package of Fruit Drops, containing 160 Calories (40 grams of carbohydrate), for each hour of exercise is likely more than enough to fuel most activities, especially if adequately hydrated with something like our Exercise Hydration Mix which contains an additional 80 Calories (20 grams of carbohydrate) per 500 ml serving.
Carbohydrate need and usage, however, is a highly individual thing and specific to the type, intensity, and duration of exercise. Thus, regulating carbohydrate consumption is ultimately the responsibility of the individual. It’s a responsibility that can be vetted through direct metabolic measurement in an exercise physiology lab or through careful self-experimentation in the field. With that in mind, realize that our usage recommendations – to have a package on hand for each hour of exercise – is simply a starting point that doesn’t trump an individual’s specific needs or their responsibility to assess them.
It’s also important to realize that the upper limit for external or exogenous carbohydrate absorption and usage during exercise for the fittest individuals is about 100 grams of carbohydrate per hour or 400 Calories. That’s not to say that we don’t burn more than 400 Calorie in an hour. What this means is that most people can’t actually absorb and use more than 400 Calories of ingested carbohydrate each hour – that above 100 grams of carbohydrate in a single hour, the extra fuel is not likely to be absorbed or used, and only increases the risk for gastro-intestinal distress, even if more calories are actually being burned by the body. The reality is that the energy we use during exercise is highly dependent upon the fat and carbohydrate (i.e., glycogen) we have stored in our bodies. The exogenous carbohydrate we consume only supplements what is stored.
With all that in mind, a solid foundation for better understanding the calories that one needs during exercise can be found in the Feed Zone Portables cookbook (32). As a general rule, for activities lasting 2 to 6 hours in length, a reasonable goal is to replace half the calories burned per hour. Measuring calories accurately is it’s own problem that is addressed in detail in the Feed Zone Portables. But, for perspective, a 154 lb person walking at 3 mph will burn about 230 Calories per hour. At a 12-minute mile or 5 mph, the energy requirement goes up to 600 Calories per hour. At a 6-minute mile or 10 mph, the energy needed will be just over 1000 Calories per hour. So unless you’re able to hold an exercise intensity equivalent to a 6-minute mile pace for more than 2 hours, it’s unlikely that you’ll ever need to consume more than 100 grams or 400 Calories per hour, which just happens to be the upper limit of what our gastrointestinal system can even absorb per hour while exercising. What this means is that we don't think anyone needs or can consume more than 2.5 packs of Fruit Drops per hour.
Ultimately, usage is about context. Energy rich foods and simple sugars like those found in our Fruit Drops are great if we are exercising for prolonged periods of time, but not great if we are sedentary or exercising for short durations. Moreover, even for the fittest athletes there is an upper limit for how much carbohydrate that can be consumed and absorbed, so relying on and improving our ability to use stored glycogen and fat to reduce our need for exogenous carbohydrate is an important key to endurance performance. When all is said and done, our Fruit Drops are simply a convenient and extremely simple carbohydrate supplement that is a great alternative to freshly made portables when we don’t have the time to be in the kitchen or as a safety net in our pocket or pack for situations when we find ourselves needing more energy than we thought. So keep a pack or two handy for whenever you’re on the move.
Allen Lim, PhD
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Health agencies refer to the formula in our Rescue Hydration Mix as an “ORS,” which stands for “Oral Rehydration Solution” or “Oral Rehydration Salts.” An ORS is a drink specifically intended to rehydrate children and adults who are dehydrated from diarrhea. Compared to common sports drinks, our Rescue Hydration Mix, which is based on recommendations developed by the World Health Organization (WHO), contains more sodium, less sugar, as well as and a small amount of zinc. Unlike the WHO formula, however, our mix also includes the use of real fruit and higher quality electrolytes for taste and function without any of the excess flavoring agents, artificial sweeteners, coloring agents, or emulsifiers found in some commercially available oral rehydration solutions. Use Rescue Hydration mix as a non-synthetic alternative to oral rehydration solutions laden with excess ingredients, to rehydrate anytime you or your kids need to quickly replace water and electrolytes.
The Story Behind Rescue Hydration Mix
We developed our Exercise Hydration Mix to rehydrate people when they’re sweating without the insult of neon colors and excess ingredients common to many sports drinks. But sweating isn’t the only way that people can become dehydrated.
Dehydration is also a huge problem when people, especially kids, are sick and experiencing diarrhea. In cases of diarrhea, large amounts of fluids and electrolytes can be lost when the intestinal wall becomes impaired due to a virus or bacteria. The result is that water and important electrolytes like sodium spill from inside the body across the intestinal wall into the gut and down the bowels where dehydration eventually announces itself in an explosive crescendo. As uncomfortable as this might be, it’s not the discomfort of diarrhea that is the issue; it’s the risk of death from dehydration and the loss of electrolytes. In fact, the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) report that in developing countries dehydration due to diarrheal diseases is the second leading cause of death in children under five years of age – deaths that are easily preventable with the use of Oral Rehydration Salts (ORS) (1, 2, 3).
Oral Rehydration Salts (ORS) are powdered mixes containing a relatively high amount of sodium and a little bit of sugar or glucose that, as the name implies, rehydrates people by optimizing the replenishment of water and electrolytes (1). The mechanism behind an ORS is relatively simple. Not only does an ORS help replace what is lost, the addition of sodium and glucose to water actually helps improve the transport of water across the small intestine, or gut, back into the body.
The water we drink can move across the intestinal wall into the body in two ways. The simplest way is passively through a process called osmosis. Osmosis is driven by the difference in the concentration of dissolved molecules or solutes on either side of the intestinal wall. The important fact to understand is that water moves from the side with the lower solute concentration to the side with the higher solute concentration. The solute (or molecular concentration) of a solution is measured as a solution’s osmolarity (Osm/L). The osmolarity inside the body is measured as blood osmolarity, which is normally about 280 mOsm/L. Thus, if someone drinks a solution with an osmolarity lower than blood (<280 mOsm/L), water will move passively from inside the gut into the body (low to high). Likewise, if someone drinks a solution with an osmolarity greater than blood, water will move from inside the body into the gut, potentially causing bloating or diarrhea. This highlights one of they key problems with osmosis; that water movement depends on a favorable concentration gradient, which may or may not be present depending upon what someone is drinking or eating.
Fortunately, water transport into the body can also be facilitated by the active co-transport of sodium and glucose. When sodium and glucose are present, they are actively transported together across the small intestine into the body through the use of energy requiring pumps, which also opens a channel for the entry of water. Specifically, for every 2 molecules of sodium and 1 molecule of glucose that are transported into the body, 210 molecules of water are also transported (4). Thus, the addition of sodium and glucose to a solution greatly improves the movement of water back into the body – an extremely simple remedy that can literally save lives.
Because of this, the World Health Organization has provided guidelines for the production of Oral Rehydration Salts. These guidelines are part of the public domain and are used to help encourage the production of a cost effective ORS for developing countries and the general population (3). They call for specific amounts of sodium (1700 mg/L), potassium (784 mg/L), glucose (13.5 g/L), and zinc (10 mg/L) at an osmolarity lower than blood (245 mOsm/L). Sodium and potassium replace the two most important electrolytes lost due to diarrhea, while the addition of glucose along with sodium improves water re-absorption. Finally, zinc has been shown to help prevent diarrhea and is now considered a critical ingredient in the formulation of ORS. While the mechanism behind how zinc works is not entirely clear, it’s thought that zinc improves immune function at the intestinal wall, helping to repair the initial intestinal damage or insult causing the diarrhea (5, 9). All said, the ultimate goal is a high sodium, low sugar, low osmolarity drink that facilitates water and electrolyte replenishment and absorption by both osmosis and the active transport of sodium and glucose while also providing small amounts of zinc for improved gut health.
While the guidelines provided by the WHO are profound and extraordinarily important to public health, the biggest problem with ORS is the taste. Making ORS exactly to WHO specifications results in a taste profile that we can only describe as a chalky sweat with slightly bitter and metallic notes. It may be for this reason that in the United States, it's common to find that many commercially available ORS use less sodium (1000-1200 mg/L) and include artificial sweeteners, flavoring agents, chemical colors, and emulsifiers in their formula. This raises the osmotic pressure of some commercially available ORS from the osmolarity recommended by the WHO (245 mOsm/L) to values greater than blood (> 280 mOsm/L)*, which hampers functionality in an attempt to improve the look and palatability. The irony is that, we feel, these ingredients only marginally improve the taste, masking the salt and electrolytes with a synthetic and unnatural flavor by using ingredients that aren’t recognized by the body and that may contribute to additional gastrointestinal distress due to the higher osmolarity.
This problem of excess synthetic ingredients was the same problem that we at Skratch Labs experienced with sports drinks – a problem that motivated the formulation of our Exercise Hydration mix. Thus, we saw an opportunity to not only improve the taste of the WHO ORS formula but to eliminate the excess chemicals used by some manufacturers of ORS. We didn’t want our kids, our loved ones, or ourselves to be drinking something when they were sick that was akin to a toxic waste dump. More importantly, we knew we could help and we wanted to help.
This hit home for us when our friend, Audie, a Peace Corp worker in Mozambique asked if we could donate some drink mix to the village she lived and worked in. What we learned from Audie was that the kids in her village wouldn’t drink the WHO formula that they were provided by relief agencies because of the taste and she needed an alternative. So when Audie’s family went to visit her in Mozambique we sent as much of a high electrolyte and low sugar drink mix as they could deliver to try. That little trial was a huge success. Both the kids and adults loved the mix and when a number of the kids became sick with diarrhea, it proved highly effective as a remedy to treat their dehydration, not just because of the high level of electrolytes but because they actually wanted to drink it.
That experience pushed us to consciously formulate a product that more closely met the guidelines set forth by the WHO. In doing so, we learned that the formula recommended by the WHO was a balance between cost and efficacy. It’s a formula that not only has clinical relevance; it’s a formula that also has to be made cheaply in developing countries. Not bound by cost, we decided to make a formula that met the WHO guidelines but that used more of the very expensive and preferable citrate based salts like sodium citrate and potassium citrate instead of relying on cheaper chloride based salts like sodium chloride and potassium chloride. We had previously discovered that, for some athletes, high amounts of chloride could be irritating to the gut when we used those salts to make our sports drink. We also focused on the taste of our formula using real fruit for flavor and a ratio of cane sugar and glucose that helped improve the taste and enhance the absorption of sugars (6).
The result was our Rescue Hydration Mix - a formula with 1500 mg of sodium, 500 mg of potassium, 17 g of glucose (32 gram total sugar), and 10 mg of zinc per liter of water with an extremely low osmolarity of 225 mOsm/L*. By avoiding excess ingredients, we were able to make our drink slightly sweeter than the WHO formula, by using real sugar instead of artificial sweeteners, and still have a significantly lower osmolarity than either the current WHO formula or other pediatric electrolyte solutions. At the same time we kept the appropriate ratio of glucose to sodium in the mix to maximize water absorption by the co-transport of glucose and sodium (4). Finally, we lowered the overall electrolyte content slightly compared to the WHO formula to improve the taste, while still using significantly more electrolytes than similar commercially available ORS. Ultimately, by not being constrained by cost, we were able to make subtle changes that we believe improve on the WHO guidelines with respect to taste and function.
Although our Rescue Hydration Mix was specifically based on the WHO guidelines for kids and adults experiencing dehydration due to diarrhea, many of our customers have found that the high sodium and lower sugar content also make it a great product for use when dehydrated for any reason. What we know is that while most sports drinks and electrolyte replacement products are not optimized for the dehydration associated with diarrhea, we have found, like many of our customers, that our Rescue Hydration Mix is very effective for remedying other forms of dehydration not associated with diarrhea - a fact that is often shared with us by many late night revelers.
Ultimately, our Rescue Hydration Mix with its high sodium and relatively low sugar content is designed to improve the absorption of water and electrolytes back into the body. At 1500 mg of sodium per liter, our Rescue Hydration Mix has about twice the sodium of our Exercise Hydration Mix (720 mg Na+/L) and about half as much sodium as our Hyper Hydration Mix (3500 mg Na+/L). Given that sweat sodium can be highly variable (7), for those who lose more sodium than either our Exercise Hydration Mix or other sports drink formulas provide, our Rescue Hydration Mix can be a great way to replace lost sodium especially after a bout of exercise that causes a large fluid and sodium loss.
The one caveat is that our Rescue Hydration Mix contains 45% of the USRDA for zinc (5 mg per 500 ml serving & 10 mg per liter). While a number of papers have shown that zinc can be important to immune function when sick or for general health (8, 9), it’s important to realize that drinking too much of our Rescue Hydration Mix when not sick may lead to consuming an inappropriate amount of zinc. Chronic (60-450 mg per day) or acute over-ingestion (>450 mg) of zinc can result in nausea, vomiting, a loss of appetite, abdominal cramps, diarrhea, and headaches (10, 11). The Food and Nutrition Board (FNB), lists the upper daily limit of zinc in infants to young adults at a range from 5 to 34 mg (7-12 mo = 5 mg, 1-3 yrs = 7 mg, 4-8 yrs = 12 mg, 9-13 yrs = 23 mg, 14-18 yrs =34 mg) and adults at 40 mg (10). For an adult, to reach this upper daily limit, one would need to drink 4 liters or 8 x 16.9 ounce servings of our Rescue Hydration Mix in one day. For that reason, we don’t recommend that anyone drink more than 8 servings of Rescue Hydration Mix per day. Simply put, it is not an alternative to our Exercise Hydration Mix or Hyper Hydration Mix when high volumes of fluid are required during activity.
In summary, we designed our Rescue Hydration Mix to help kids and adults who are dehydrated due to diarrhea. We developed our mix when we realized the importance of ORS to public health, especially in developing countries and saw room to improve the taste of the WHO formula while eliminating the excess ingredients common to a number of commercially available formulas. The net result is an ORS that we believe tastes better and that does not contain excess ingredients like emulsifiers, coloring agents, flavoring agents or artificial sweeteners, giving it an extremely low osmolarity. That low osmolarity combined with the addition of sodium and glucose ensures the rapid absorption of water by both passive (osmosis) and active mechanisms (facilitated transport). Because other drink mix formulas are not designed specifically to deal with dehydration associated with diarrhea in either kids or adults, our Rescue Hydration Mix fills a very unique market and need. That said, our Rescue Hydration Mix can also be used in any situation that involves severe dehydration. But since our Rescue Hydration Mix contains zinc, which has been shown to be important to the cessation of diarrhea by enhancing immune function in the gut, no more than 8 servings of our Rescue Hydration Mix is recommended per day. Like our other drink mixes, this product fits our mission to provide people with products that help them take care of themselves and their families. While we started Skratch Labs because we care about sport and performance, the reality is we care a lot more about people and their health.
Allen Lim, PhD
1. End preventable deaths: Global Action Plan for Prevention and Control of Pneumonia and Diarrhoea. World Health Organization / The United Nations Children’s Fund (UNICEF), 2013.
2. Diarrhoea: Why Children are still dying and what can be done. World Health Organization / The United Nations Children’s Fund (UNICEF), 2009.
3. Oral Rehydration Salts: Production of the new ORS. World Health Organization / The United Nations Children’s Fund (UNICEF), 2006.
4. Wright, E. M., & Loo, D. D. (2000). Coupling between Na+, sugar, and water transport across the intestine. Ann N Y Acad Sci, 915, 54-66.
5. M Imran Qadir, A Arshad, B. Ahmad. Zinc: Role in the management of diarrhea and cholera. World J Clin Cases. 2013 July 16; 1(4):140-142.
6. Jeukendrup, A. E., & Moseley, L. (2010). Multiple transportable carbohydrates enhance gastric emptying and fluid delivery. Scand J Med Sci Sports, 20(1), 112-121.
7. Shirreffs, S. M., & Maughan, R. J. (1997). Whole body sweat collection in humans: an improved method with preliminary data on electrolyte content. J Appl Physiol, 82(1), 336-341.
8. Maywald, M., & Rink, L. (2015). Zinc homeostasis and immunosenescence. J Trace Elem Med Biol, 29, 24-30.
9. Basnet, S., Mathisen, M., & Strand, T. A. (2014). Oral zinc and common childhood infections-An update. J Trace Elem Med Biol.
10. Lewis MR, Kokan L. Zinc gluconate: acute ingestion. J Toxicol Clin Toxicol 1998;36:99-101.
11. Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc . Washington, DC: National Academy Press, 2001.
*Osmolality in mOsmol/kg, which is used synonymously with osmolarity measured in mOsmol/L, was measured at the Applied Exercise Science Laboratory in the Department of Integrative Physiology at the University of Colorado at Boulder using a Wescor VAPRO® Vapor Pressure Osmometer, manufactured by EliTech Group Solutions, Princeton, NJ using commercially available oral rehydration solutions purchased at a local grocery store. 2015.
At Skratch Labs, all of our hydration products are driven by science but crafted and sold as real food, not as supplements. While it’s a subtle distinction for some, it’s a fundamental difference that defines everything we do. For example, we are meticulous about the formula in our Exercise Hydration Mix, making sure that we have an electrolyte ratio that best matches what we lose in sweat and a blend of sugars that optimizes absorption in the small intestine to prevent gastrointestinal distress (i.e., gut rot). At the same time, none of our drink mixes contain flavoring agents or artificial ingredients. Instead, we use whole functional foods that have been dried and crushed like raspberries, oranges, lemons, mangos, and pineapples to flavor and enrich our line. This gives all of our drinks a simple and clean taste that hydrates us while also providing the nutritional benefits associated with the foods we use. Most recently, we took this a step further by developing a flavor using Matcha – a type of green tea that is consumed whole rather than brewed, making it convenient and incredibly nutrient dense compared to other teas.
Like many plant-based foods, tea is a functional food. A functional food contains essential nutrients like carbohydrate, fat, protein, vitamins, and minerals as well as biologically active compounds that affect one’s physiology and that can contribute to disease prevention (Hayat, 2013; Deldicque, 2008). The natural compounds in foods that are not essential nutrients but that are important to our health are referred to as phytochemicals or phytonutrients. Phytochemicals in turn have a broad and complex classification system that has generated a litany of jargon in the marketing and science surrounding functional foods as well as an equivalent amount of confusion when it comes to understanding what we are actually consuming and whether it’s actually good for us.
For now, I’ll skip out on describing all of the classes of phytochemicals but mention the ones that are more common and relevant to tea. For example, one class of phytochemicals are alkaloids that include caffeine and caffeine-like compounds like theobromine and theophylline found in tea, coffee, and cocoa. Another class of phytochemicals are polyphenols which are further categorized into non-flavonoids and flavonoid compounds. Non-flavonoids include compounds like reseveratrol common to grapes and wine while flavonoids include compounds like anthocyanins, quercitin, and tanins, which can be further classified into catechins or flavan-3-ols. It’s these catechins that are specifically found in high quantities in tea and which can be further broken down into four major types of catechins in tea including epigallocatechin-3-gallate (EGCG), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and epicatechin (EC) that are the compounds that impart many of the health benefits associated with tea (Kim, 2014).
While all of these names are confusing all by themselves, the confusion is often confounded because when people describe a particular phytochemical, it’s common to use the different names within a particular class as synonyms for one another. For example, EGCG can be described as a catechin. A catechin can be described as a tannin. A tannin can be described as a flavonoid. A flavonoid can be described as a polyphenol. And finally, a polyphenol can be described as a phytochemical. To keep things easy and coming full circle, we’ll just describe good things in food that aren’t essential nutrients as phytonutrients and only talk about specific compound like the caffeine or EGCG in tea when appropriate.
With that in mind, the reason that phytonutrients in tea, specifically, catechins like EGCG have physiological significance and a number of health benefits is because they have an incredible array of unique attributes that include anti-oxidative (Jowko, 2011; Panza, 2008), anti-inflammatory (Hagiwara, 2014; Haramizu, 2013; Nicod, 2014), anti-carcinogenic (Sato, 1999; Siddiqui, 2014), anti-hypertensive (Khalesi, 2014; Mousavi, 2013; Onakypoya, 2014), anti-microbial (Hagiwara, 2014; Lin, 2014; Pang, 2014), neuro-protective (Noguchi-Shinohara, 2014), DNA protective (Ho, 2014), cholesterol lowering (Eichenberger, 2009; Kono 1996; Onakypoya, 2014; Yousaf, 2014), and thermogenic or metabolism increasing properties (Hodgson, 2013; Jeukendrup, 2011). And ultimately, all of these things are good things, especially when reviewing the wide array of research studies describing health benefits for specific diseases like cardiovascular disease (Ghanbari, 2014; Santesso, 2014), cancer (Butt, 2013; Green, 2014; Greenberg, 2013; Huang, 2014; Inoue, 1998; Wang, 2014), urinary tract infections (Katz, 2014), type II diabetes (Pham, 2014; Venables, 2008), arthritis (Byun, 2014; Yang, 2014; Riegsecker, 2013), stroke (Nabavi, 2014), obesity (Byun, 2014), dental diseases (Gaur, 2014), neurodegenerative diseases like Parkinson’s (Qi, 2014; Gao, 2013; Albarracin, 2012; Tanaka, 2011), and dermatological issues (Scheinfeld, 2013; Pazyar, 2012).
Beyond these disease preventing properties, tea also can act as a stimulant due to naturally occurring caffeine as well as an amino acid called L-theanine, which has been show to be a mood stabilizer, working synergistically with caffeine to improve focus (Yoto, 2014; Camfield, 2014; Ross. 2014; Giesbrecht, 2010). And while much has been made about caffeine as a performance enhancer due to its ability to mobilize free fatty acids (Jeukendrup, 2011), improve alertness (Beaven, 2013), and enhance glycogen re-synthesis (Beelen, 2012; Taylor, 2011) it’s also clear that those effects only come at high doses of caffeine (3-6 mg per kg of body weight) and are better if you are unaccustomed to caffeine (Burke, 2008; Ganio, 2009; Deldicque, 2008). In addition, it’s also clear that at very high doses, caffeine can have negative affects ranging from sleep disturbance to anxiety to cardiovascular complications (Youngstedt, 1998, 2000; Rogers, 2013; Chrysant, 2014).
From an exercise standpoint, there’s less evidence that phytonutrients beyond caffeine like catechins in tea are beneficial to actual performance. That said, some studies in mice have shown improved endurance capacity in mice associated with EGCG supplementation resulting from an increase in fat use (Murase, 2005) as well as less of an age related decline in endurance performance (Murase, 2008). Interestingly, one in vitro (outside of the body) study has shown that EGCG can help prevent muscle wasting (Mirza, 2014) which may have implications for humans during exercise or in recovery from exercise, though those implications may be a bit of a stretch, especially since actual benefits in exercising humans are unclear. For example, a single 640 mg dose of EGCG in soccer players showed no reduction in oxidative stress or muscle damage (Jowko, 2012). An acute dose of green tea catechins (22 mg per kg of body weight), however, immediately after exercise in Tae Kwon did show improvements in immune function (Lin, 2014). Finally, in one human study, short term consumption (945 mg over 48 hours) of EGCG has been shown to increase maximal oxygen consumption without changes in cardiac output, hinting a greater ability of muscle to extract oxygen (Richards, 2010). Unfortunately, much more research is needed to bear out any real world performance benefits.
That all said, we weren’t just thinking about the potential health or performance benefits of tea when we developed our newest Exercise Hydration Mix that contains Matcha – a type of green tea. For what it’s worth, like many people, we just like tea. We like the way it tastes and how it makes us feel. Unfortunately, we don’t always have the time or resources to brew it. This is where Matcha comes in. Like all other teas, Matcha comes from the plant Camillia Sinensis. There are three basic types of tea – green, oolong, and black tea. They’re distinguished by whether the plants are allowed to ferment before drying. Green tea is unfermented, oolong is partially fermented and black tea is fermented. The fermentation process changes the amount of phytonutrients available. For example, black tea is higher in caffeine than green or oolong, but green tea is higher in catechins like EGCG than either oolong or black tea. Unlike other teas, Matcha is unique because it’s grown in the shade, significantly increasing its chlorophyll content—the component in plants that make them green and that may also add to the positive health benefits of tea (Jiang, 2013). In addition, Matcha is not brewed. Instead, the entire leaf is ground into a powder and consumed whole. Because the entire leaf is consumed, this increases the amount of phytonutrients that can be consumed and concentrated into a drink, compared to brewed tea. But most importantly, because Matcha is a powder it’s actually possible to blend it into a drink mix making it a convenient and highly functional ingredient.
A single 16 oz serving of our Exercise Hydration Mix with Matcha + Lemons contains about 500 mg of whole ground Matcha. Traditionally, if someone were making a 16 oz serving of Matcha tea, they might use about 2000 mg or a teaspoon of whole Matcha powder. So per serving we’re about a quarter of a typical serving of Matcha that someone might traditionally consume. The reason we did this is that our assumption is that during prolonged exercise someone might consume multiple servings of our Exercise Hydration Mix and we wanted to make sure that people didn’t over-consume Matcha relative to what’s traditionally consumed. In addition, this helps to keep the overall flavor profile light and prevents the overly tannic taste profile that is common when drinking Matcha and other teas. This also means that the amount of caffeine per serving is lower at approximately 16 mg per 16 oz serving. As a point of reference an 8 oz cup of coffee might have anywhere from 70-100 mg of caffeine whereas a typical 8 oz cup of Matcha tea might have about 30-40 mg of caffeine. While the amount of caffeine in our Exercise Hydration Mix with Matcha + Lemons is not high, it is there and it is natural with 5 servings equaling a cup of coffee. Over the course of a long day, this small amount can add up if someone is consuming enough to keep hydrated, which is the ultimate purpose of our line of Exercise Hydration mixes.
Although it’s nice to know that teas, in particular, green teas like Matcha have a host of potential health benefits (Hayat, 2013), it’s unlikely that a single drink of anything is likely to improve performance or health (Jowko, 2012; Randell, 2013). The reality is that we never intended nor do we think that our Exercise Hydration Mix with Matcha + Lemons is, by itself, a panacea for poor health or performance. Like all things in life, it’s important to always look at the big picture when thinking about one’s well being. That picture includes one’s overall diet, physical activity, stress level, social support, sleep and innumerable other factors spread over a lifetime. Ultimately, what we believe is that using whole food ingredients with known functional benefits is just better than the common practice of using artificial ingredients like coloring agents, emulsifiers, and synthetic sweeteners that may actually be harmful to our health (Simmons, 2014). By using Matcha we don’t just get a functional food, we get an incredible and refreshing taste that helps to encourage drinking and that keeps us hydrated with all of the potential upsides of real tea.
Coconut water is naturally sweet and high in the electrolyte potassium. So it’s not uncommon for people to ask about the use of coconut water as a real food sports drink. But, when assessing the use of coconut water as sports drink, what comes to mind is C.G. Jung’s idea of “shadows” – the aspects of our lives that are in actuality completely opposite of what we think or perceive. It’s an apt reference point, because if sports drinks have a dark shadow, it’s coconut water. Coconut water is fine if you just want something real to drink when you’re not exercising or for short duration exercise (< 90 minutes or less) (1), but if you’re sweating a lot during prolonged exercise, it’s definitely the wrong choice.
In the realm of human physiology, coconut water is the exact opposite of what we need to replace the sweat we lose when we are exercising. The reason for this is that the primary electrolyte in coconut water is potassium, whereas the primary electrolyte in sweat is sodium. More specifically, 16 oz of coconut water contains 950 mg of potassium and only 50 mg of sodium. In contrast, 16 oz of sweat contains anywhere from 200 to 700 mg of sodium, and only about 50 to 110 mg of potassium (2,3) (Table 1).
450 ± 250
80 ± 30
25 ± 17
6 ± 6
Table 1. Electrolyte Content in 16 oz of Coconut Water, Skratch Exercise Hydration Mix, and Sweat.
The high sodium and low potassium content of sweat reflects the relatively high sodium and low potassium concentration found in our blood or vascular space that feeds our sweat glands. This difference is due to the fact that pumps in our cell membranes that set up the chemical-electrical gradients across cells that allow proper cell function and communication, do so by pumping potassium into cells and sodium out of cells, making intracellular (inside cells) potassium levels very high compared to sodium, and extracellular (outside of cells) sodium levels very high compared to potassium.
Because water equilibrates between the major spaces across the body, which include our vascular space (blood vessels), extracellular space, and intracellular space, when we consume an excess of sodium we tend to shift water into our vascular space and when we consume an excess of potassium we tend to shift water into our cells. This is why, in some people, excess sodium consumption can raise blood pressure. Likewise, when we consume foods or liquids that are very high in potassium, we tend to increase our intracellular water stores.
During exercise, however, increasing the water volume in our vascular space is what is critical to help provide the necessary blood volume to deliver oxygen, eliminate heat, and provide valuable fluid for sweat. So in the context of exercise, consuming water and ample sodium is much more important than consuming potassium, not just to replace what we lose in sweat, but to maintain an adequate blood volume to meet the increased demands on our circulatory system especially in the heat (4,5). In contrast, consuming coconut water or plenty of fruits and vegetables that are high in potassium along with water isn’t a bad strategy for rehydrating cells when recovering, though it’s important to remember that we don’t deplete nearly the same amount of potassium during exercise as we do sodium.
In most cases, drinking a bottle or two of coconut water during exercise isn’t going to kill us, as our kidneys are pretty good at keeping our electrolyte concentrations in check, especially if consumption isn’t excessive. But it definitely isn’t going to help us during exercise compared to a good sports drink with adequate sodium. That said, drinking only coconut water for long periods of time while exercising in the heat is one of the rare situations that could lead to dangerous electrolyte imbalances within the body that may be extremely harmful. While, a lot has been written about the hyponatremia that can occur if we only drink water during prolonged and heavy exercise in the heat, drinking only coconut water can exacerbate the situation, since the excess potassium consumption only compounds the inadequate sodium replacement (6). Thus, in situations where drinking water alone can be harmful, be assured that drinking only coconut water may be just as is or even more harmful (7).
Ultimately, coconut water is the exact opposite of what we need when we are sweating heavily during exercise. It’s like Bizarro – Superman’s opposite – a character that Alvin Schwartz, one of the original writers for the Superman strip, found inspiration for through C.G. Jung’s “shadow” archetype. Just like Bizarro and Superman, there are a lot of similarities between coconut water and the all-natural Exercise Hydration Mix on the surface – both contain the same amount of calories, both contain electrolytes, and both are made with real food ingredients. But don’t be fooled, when you take a closer look, the reality is that coconut water is the Bizarro sports drink.
1. Kalman, D. S., Feldman, S., Krieger, D. R., & Bloomer, R. J. (2012). Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. J Int Soc Sports Nutr, 9(1), 1.
2. Shirreffs, S. M., & Maughan, R. J. (1997). Whole body sweat collection in humans: an improved method with preliminary data on electrolyte content. J Appl Physiol, 82(1), 336-341.
3. Adams, R., Johnson, R. E., & Sargent, F. (1958). The osmotic pressure (freezing point) of human sweat in relation to its chemical composition. Q J Exp Physiol Cogn Med Sci, 43(3), 241-257.
4. Sawka, M. N., & Montain, S. J. (2000). Fluid and electrolyte supplementation for exercise heat stress. Am J Clin Nutr, 72(2 Suppl), 564S-572S.
5. Sharp, R. L. (2006). Role of sodium in fluid homeostasis with exercise. J Am Coll Nutr, 25(3 Suppl), 231S-239S.
6. Schucany, W. G. (2007). Exercise-associated hyponatremia. Proc (Bayl Univ Med Cent), 20(4), 398-401.
7. Noakes, T. D., Goodwin, N., Rayner, B. L., Branken, T., & Taylor, R. K. (1985). Water intoxication: a possible complication during endurance exercise. Med Sci Sports Exerc, 17(3), 370-375.
The Back Story:
For the last two years, we’ve been making a secret drink mix that is extremely high in sodium to over-hydrate or “hyper-hydrate” athletes immediately before they put themselves in grueling situations where they end up sweating more than they can possibly drink.
Given its purpose, we called the product our Hyper Hydration Drink Mix and kept access to it limited to only our most hot and sweaty customers – NASCAR drivers, fire fighters, and a handful of professional runners and cyclists. We weren’t trying to be elite by limiting the product’s access. Rather, we had legitimate concerns about the product’s taste and worried about what might happen if the product was used inappropriately or without hands on instruction.
So for almost two years, we tinkered, studied, and worked carefully with a cast of characters – some very fast, others slow, but all extremely smart & sweaty - to evolve our formula until we reached a point that we felt, when used as directed, the product was safe, effective, and palatable for the general athletic population to use as a method to preemptively hydrate before events known, or with the potential, to elicit severe dehydration.
It took us a while, but we felt it important to take the time and care. As part of that diligence, we want to emphasize that our Hyper Hydration Drink Mix is not a sports drink or a “use every time you exercise” product. More to the point, this product is not intended for casual hydration. In fact, we encourage you not to use our Hyper Hydration Drink Mix until you finish reading this blog, talk to your coach, health care professionals, visit google, and give your individual situation and this product some real consideration. It may not be for you. But if you decide it is, then our experience has been that it’s probably exactly what you’ve been looking for.
First, a Review of Sweat – Water & Salt:
When it’s hot or more appropriately when we get really hot, whether it’s through intense exercise or from baking under a garish sun, we sweat to cool our bodies. Without that sweat and the evaporative cooling that comes with it we can overheat and literally start cooking ourselves from the inside out, which isn’t exactly good for either performance or one’s health. Unfortunately, as we sweat we also dehydrate, losing precious water and salt, both of which are critical for normal bodily functions. It’s a bit of a catch 22. Either overheat or dehydrate or both – all of which are bad.
While the body is almost 60% water by weight, a 70 kg person doesn’t have 42 liters (1 kg of water = 1 L of water) of water to spare to keep them cool. Depending upon the situation (airflow, temperature, work intensity), exercise performance can suffer with as little as a 2-3% drop in body weight due to dehydration. By the time someone loses 10% of body weight from dehydration (7 kg or 15.4 lbs for a 70 kg or 154 lb person), it’s likely that they are critically ill or very close to it. Unlike stored fuel in the form of carbohydrate or fat, we’d kill ourselves before we even came close to tapping into all of our water reserves.
In addition to thinking about total body water, it’s also important to realize that the water stored in our body isn’t all in one big reservoir. About two-thirds (2/3) of it is inside our cells (intracellular space) while the other one-third (1/3) is outside of cells (extracellular space). Of the water outside of the cells only one-fifth (1/5) of it is in the circulatory system as plasma in the blood (intravascular space), while the other four-fifths (4/5) lies in the space between blood vessels and cells (interstitial space).
The net result is that for an average person our blood volume is only about 5-6 liters, with only about 2.5-3 liters of that being water or plasma. Because maintaining that small plasma volume is critical to keeping our cardiovascular system functioning and precious oxygen flowing to our cells, it’s very easy to see how quickly even a small amount of dehydration can affect performance and thermoregulation (i.e., the maintenance of a stable body temperature). Although, our body can quickly shift water from one body space to another to maintain central blood volume and blood pressure, in the heat or during heavy exercise, sweat rates can easily reach rates as high as 2-4 liters per hour, which puts an incredible strain on our total body water reserves and on the availability of water in our cardiovascular system. One way to think of it is that in an hour or two of intense exercise in the heat, our bodies need to find a way to replace almost all of the water in our blood.
Equally important, however, is the fact that the water in our plasma or blood isn’t just water – it’s more of a salty soup, containing about 9 grams of sodium chloride per liter (3.5 grams from sodium and 5.5 grams from chloride) – an amount that is similar to the sodium concentration in chicken noodle soup which comes in at 3 to 4 grams of sodium per liter. Since the water in our bodies or more specifically in our plasma is so salty, the fluid that enters any one of the two million sweat glands across our skin is also salty. In fact, while a number of electrolytes like potassium, calcium, and magnesium are also lost in sweat, sodium chloride makes up the overwhelming majority of the electrolyte loss in sweat. For this reason, electrolyte loss in sweat is really synonymous with salt loss. More importantly, it’s the loss or dilution of sodium, not chloride, that negatively affects our physiology – a phenomenon called hyponatremia that can result in a host of problems that range the gamut from fatigue, confusion, headache, nausea, muscle cramps, seizures, and in rare cases death. Because of these potential issues, getting a handle on the concentration of sodium in sweat (i.e., “sweat sodium”) and replacing that sodium in addition to water, instead of water alone, when dehydrated from heavy sweating is paramount to performance and survival.
Unfortunately, getting a handle on the amount of sodium we lose in sweat isn’t that easy. Unlike the relative ease of estimating water loss through changes in body weight using a simple bathroom scale, measuring sweat sodium requires expensive and less accessible equipment. When sweat sodium is measured, however, incredibly large differences between individuals are found, with sodium concentrations ranging from 300 to 2000 mg per liter of sweat with a median somewhere between 700 to 800 mg per liter. The bottom line is that the sodium concentration of sweat is not a “one size fits all” phenomena.
The reason behind this massive sweat sodium range is primarily genetic. When sweat first enters the sweat gland it has the same sodium concentration as blood at 3500 mg per liter (3.5 g/L). But as that sweat moves through the duct or lumen of the sweat gland towards the surface of the skin, small channels inside the duct reabsorb, on average, two-thirds of the sodium. But like many physiological attributes, the number and performance of these sodium specific channels is highly individual with a genetic basis that explains most of the extreme range in sweat sodium concentration. Non-genetic factors, however, can also affect sweat sodium. These factors include heat acclimatization (spares sodium), training (spares sodium), the sweat rate in and of itself (increases in sweat rate increase sweat sodium loss), body weight and shape (a low body surface area to mass requires more sweat), and dietary sodium intake (increases in dietary sodium increase sweat sodium loss).
Together, these genetic and non-genetic factors explain why some of us are consistently covered in white salt at the end of a long day of exercise while others are not. They may also explain why some more easily exhibit signs associated with severe dehydration and hyponatremia like cramping, nausea, fatigue, heat stress, and headaches after a prolonged period of heavy sweating despite the use of a sports drink. Ultimately, whether someone knows their sweat rate or sweat sodium, these collective signs are a real world and real time barometer that are extremely important to pay attention to and understand.
If you’ve paid enough attention to yourself during prolonged endurance exercise or during any activity that causes you to sweat at unreasonably high rates then you probably already have a pretty good sense of whether or not your current hydration strategies are adequate. But as a point of self-review, ask yourself the following questions:
There’s a possibility that you think these questions are crazy and that you answered “no” to most of them. If that’s the case and none of the issues listed above are a problem for you, then you can stop reading. Our Hyper Hydration Drink Mix isn’t for you and you don’t need to waste your time and money to try it.
On the other hand, if these questions resonate with you and you feel like you’ve just locked eyes with someone standing off in the distance - someone who really understands you, then we may be on to something. Despite our irrevocable propensity for jocularity (i.e., we like to laugh at ourselves & keep things funny), this really isn’t a laughing or joking matter. Severe dehydration resulting in both water and sodium loss can be very dangerous. But so can loading up on a lot of water and sodium that you don’t need, which is essentially the solution that we’ve come up with to help all of the folks out there who do answer the questions above with a definitive “yes.”
The Solution (Common sense, inspiration, and the formula):
One thing to realize is that, despite the product we’ve developed, there is no one simple solution to all of the problems listed above. Ultimately, common sense and safety during any activity needs to rule supreme. So as a reminder, realize that you still need to take care of yourself with proper nutrition, sleep, and training. No single product will ever make up for self-awareness and consistent preparation. With that in mind, also realize that science is not a set of facts, it’s the testing of theories. And in the realm of your personal performance, you are the experiment, which requires a level of precision, care, and honesty that may lead you to conclude that our Hyper Hydration Mix does or doesn’t work for you. Ultimately, knowing how something works for you as an individual is far more important than knowing how it works for others, despite the fact that every bit of data informs our personal decisions.
That all said, the basic question we’ve been working on is how to safely and effectively maximize the water and sodium reserve within the body, in particular the volume of the intravascular space (i.e., the water & salt in the cardiovascular system, aka, vascular space or plasma volume), to preemptively combat dehydration. Obviously, one strategy is to simply drink more water and increase dietary salt intake in the week or days before an event. Many bowls of miso soup come to mind. In addition, another practical idea is to dramatically increase the intake of carbohydrate in the week or days before an event, since stored carbohydrate in the form of muscle glycogen contains a significant amount of water. If these two strategies are implemented properly, many athletes will gain anywhere from 3-5 pounds of water weight – an indication that they are properly tapered and nourished before an event.
While there are a host of other techniques that have been used, with varying efficacy, to hyper hydrate the body immediately before exercise, we’ve drawn inspiration for our Hyper Hydration Drink Mix from the most effective and commonly used technique for treating severe dehydration and for increasing intravascular volume - IV hydration using normal saline. Normal saline, also known as an isotonic saline solution, has the same osmolarity and the same sodium chloride concentration as the plasma in the vascular space, making it a perfectly balanced solution to quickly rehydrate the body.
As a point of education or review, osmolarity refers to the number of molecules per liter of solution and can be thought of as analogous to the number of total passengers on a plane. This is different than concentration, which accounts for the mass or weight of those molecules in a given liter of solution and is analogous to the weight of the passengers on a plane. It’s the osmolarity of one solution relative to another that determines the movement of water across a membrane. In order to keep water within the vascular space, the osmolarity needs to be kept constant. Otherwise water would shift from an area of low osmolarity or osmotic pressure to an area of high osmotic pressure. Likewise, the concentration of sodium also needs to be kept constant since most physiological functions depend on a stable sodium concentration. For example, if the concentration of sodium where to decrease in the blood, also resulting in a drop in the osmolarity of blood, water would begin shifting out of the vascular space, into the interstitial or intracellular space, essentially dehydrating the cardiovascular compartment. At the same time, water would also be excreted by the kidneys to help return the concentration of sodium back to normal - a situation that would further dehydrate the body as a whole. Ultimately, osmolarity and concentration rule supreme. An ideal sports drink, for example, needs to have the same sodium concentration as sweat and a very low osmolarity compared to blood so that water in the gut can rapidly move into the blood stream. Similarly, the ideal solution to increase total body water, especially in the vascular space before sweating ensues, needs to have the same sodium concentration as blood or plasma as well as the same osmolarity making it “isotonic.”
Under the right circumstances, IV hydration with normal saline is safe and effective. But the use of IV hydration immediately before an athletic event in an otherwise healthy individual is not the right circumstance for a number of reasons. First, it’s just not practical or efficient. In fact, a number of studies have demonstrated that in patients that are conscious and free of gastro-intestinal problems, oral rehydration is easier and faster than IV rehydration. Second, the use of IV hydration is cost prohibitive for most athletes, though there are a number of reports that in some sports like American football, that the use of IV hydration pre-game is common practice, especially for athletes known to have issues with dehydration. Whether this is ethical or not is its own and final debate against IV hydration as a pre-exercise hyper hydration technique.
More importantly, however, there’s a very specific reason why normal saline is generally infused and not ingested orally. That reason is because it’s nearly impossible for someone to rapidly ingest a large volume of normal saline because of it’s taste and because of the irritation caused by the large chloride concentration. Anyone willing to drink a liter or more of a normal saline solution would likely end up feeling nauseous and vomiting. It’s that bad, so we’ve been told by our local ER doctors. Our experience with athletes has always been that when too much sodium chloride or table salt was put in solution, the chloride could be a major irritant. That said we never experienced problems with sodium chloride when it was paired with real food. It’s a funny thing but perhaps a sign that we are not yet smarter than nature when drinking a bowl of salty soup is soothing while a saline solution with the equivalent amount of salt is not. Go figure.
Based on all of this, we formulated our Hyper Hydration Mix to have the same osmolarity and sodium concentration as blood at 3.5 grams per liter. But, instead of using sodium chloride, we paired the sodium in our solution with citrate, which is essentially a neutralized fruit acid or citric acid, the primary ingredient in lime juice. One of the major benefits of using sodium citrate instead of sodium chloride is that sodium citrate is very easy on the gut. The second benefit is that citrate, unlike chloride ion, can be consumed as a substrate or fuel source for energy creating metabolic pathways, specifically as a metabolite in the Citric Acid Cycle (aka, Kreb’s Cycle), a critical pathway for the conversion of sugar and fat into energy. Finally, sodium citrate is a very strong buffer. When it comes to the control of our body’s acidity level (i.e., acid-base balance), increasing positively charged sodium ions and decreasing negatively charged chloride can actually help to buffer or make the body less acidic – an idea known as the “Strong Ion Difference.” Ultimately, this buffering capacity may have positive consequences during intense exercise, especially in the first 5 to 10 minutes, though the performance literature supporting this is mixed.
Beyond the use of a large quantity of sodium citrate instead of sodium chloride, our Hyper Hydration Mix is also paired with a small amount of cane sugar and glucose. Water movement across the small intestine can be facilitated by the co-transport of sodium and glucose, where the pairing of 1 glucose molecule to every 2 sodium molecules allows the movement of 210 water molecules across the intestine via a specific sodium-glucose transporter. This co-transport is in addition to the passive movement of water across the intestine via osmosis. Because of this mechanism, we added enough glucose to the formula so that every sodium molecule could be used to maximize the movement of water into the body.
Finally, we struggled to make this high sodium drink palatable. The answer finally came to us in the form of a mango, or more accurately, in the form of many mangos. Putting aside the science hat for a moment and considering the problem from a culinary perspective, we realized that many cultures use mango to cut the saltiness of a dish. To our happy surprise, it worked. But, it took a lot of mangos. The total number of mangos, not the science, is the real secret behind the formula, so we’ll keep that to ourselves for now. Just know that it’s the most expensive ingredient in the entire product. In fact, you’re not really buying a lot of sodium, you’re buying a lot of mangos. Still, with the lower sugar and the extremely high sodium content, there’s no way that we could ever make this product taste even close to our line of Exercise Hydration Mixes. Compared, however, to normal saline and many other sports drink on the market, we feel pretty good about where we landed, especially since we were still able to solve the problem at hand with a bare minimum all-natural approach.
Based on the number of total mango molecules, sodium molecules, and sugar molecules, we pretty much had to stop there to keep the drink isotonic at 280 mOsm/L. Although, we tried throwing more ingredients in the mix, experimenting with different levels and types of sodium salts, percentages of carbohydrate, and fruits we found that the less is more approach worked the best. For example, any more sodium or additional ingredients and we risked making a solution with too high of an osmolarity which could result in significant gastro-intestinal distress and even diarrhea. In contrast, any less sodium than what’s found in blood and we wouldn’t maximize the amount of fluid retained in the vascular space before the kidneys would filter the excess water because of changes in blood pressure or sodium concentration.
In the end, this product is intended for one specific purpose – to maximize hydration before an event that’s about to punish the participant with a heavy dose of dehydration. Our solution was to create a product that increases the total sodium and water reserve within the body. Not only is this useful for athletes who know they won’t be able to drink enough to match their sweat losses, it’s also been extremely useful for athletes who know that they lose more sodium that our Exercise Hydration Mix provides them. Ultimately, dehydration is about a loss of both water and sodium and our Hyper Hydration Mix helps athletes to maintain both. And since it’s sometimes hard to get a handle on how much sodium or water you’re about to lose, then sometimes the simplest solution is to just start with more of what you know you’re going to lose and that you know you can’t afford to lose.
Concerns with the Solution:
What’s ironic about all of this is that the high sodium content that forms the basis of our solution for extreme sweat rates is also the biggest single risk and problem with the solution. At 1700 mg for a single 500 ml serving (3.5 gram per liter), our Hyper Hydration Drink Mix is inappropriate for casual exercise use. A single serving, is similar to the amount of sodium that you’d find in two slices of Pizza Hut Supreme pizza (1720 mg Na+) or six slices of bologna (1850 mg Na+), or two cups of miso soup (2000 mg Na+). Despite the fact that all of the foods listed above are commonly consumed and thought of as safe, like our Hyper Hydration Drink Mix, they can lead to the potential for an unsafe increase in blood pressure, especially in physically inactive individuals. Thus, our biggest concern is that someone who is not healthy or is not intending to use the product mistakenly uses it, putting an inadvertent strain on their cardiovascular system.
Beyond the potential for an elevation in blood pressure, there’s also the risk that sodium sensitive individuals who don’t lose a remarkable amount of sodium in their sweat or who are already adequately hydrated will experience bloating and excessive water retention with the product. For most in this category this will lead to a little discomfort and the knock to their vanity from not looking as ripped or vascular. At some point, the excess fluid will be relieved by excess urination, which in and of itself can be a hassle or concern, especially if occurring in the middle of a workout or ride.
Another concern is that because our Hyper Hydration Drink mix already has a very high sodium concentration and osmotic pressure equal to blood, if very sweet or salty drinks and foods are paired with the product, especially in the presence of a lot of caffeine, then there is a risk that the combined osmotic pressure could overwhelm a person’s gut and cause diarrhea. So it’s important that the drink is used by itself on a relatively empty stomach.
For some, a real valid concern is that they won’t enjoy the taste. If that’s the case, we’d suggest not using it and trying to drink 2-4 bowls of miso-soup right before a grueling event with minimal access to hydration.
Finally, some athletes that we worked with were concerned that the extra water weight would hurt their power to weight ratio. While too much fuel on a helicopter can definitely keep it from flying, when it comes to performance in very intense and hot situations, despite the increase in water weight, it’s unlikely that there would be any hit to that all too precious power to weight output. If anything, the improvement in cardiac output will likely enhance performance, especially relative to competitors who are more dehydrated late in a race or event.
Practical Advice on Experimenting & Usage of Hyper Hydration:
Like most ideas concerning training and nutrition, we are all individuals and responses will vary from person to person. As a generic recommendation, we advise the following directions for use:
Based on these generic recommendations, the athletes we have worked with to develop this product have adopted varying personal strategies for the use of the product. Many find that it’s helpful to “top themselves off” the morning of an event by drinking 1 to 2 servings of Hyper Hydration Mix a few hours before competition. If they are already dehydrated from training or the previous days competition, they’ll tend to hold most of the extra fluid they consume and not urinate a lot of it away. If, however, they are adequately hydrated, then using the drink in the morning gives them time to urinate any excess fluid away before competition.
Other athletes have reported that they have good success when they begin using the Hyper Hydration Mix the day or night before a very important event as part of their taper. While simply increasing their water and dietary sodium intake might work equally as well, for some using our Hyper Hydration Mix is a simple and convenient way to bolster their water and sodium reserves. That said, it’s by no means the only way. In fact, we’ve found that some athletes simply use our product because they are unsure of where they are with respect to their hydration status on any given day. One way to get to know where your hydration stands is to get familiar with your morning body weights as well as the changes in body weight caused by training or competing in different environments. Large or sudden drops in weight are likely due to dehydration.
For athletes, who know that they are adequately hydrated, they have found that our Hyper Hydration Mix becomes more effective when they consume it closer to the start of exercise. This is because if they drink too far out from exercise, the sudden increase in blood pressure simply causes them to urinate most of the extra water away. By waiting until just before exercise, blood flow is redirected away from their kidneys while sweating begins to pull away the excess water and salt reserve. This typically creates the biggest increase in performance relative to their non hyper-hydrated competitors. That said, it only works in very hot environments and for very intense bouts of exercise or competition.
The most important thing to remember is that our Hyper Hydration Mix has very specific use parameters. It’s not a drink anytime sports drink and needs to be used carefully and sparingly with real attention to how you feel and respond. Everyone is different and what works for one person may not work for you. Be willing to experiment and test and above all else use common sense. Less is often more, especially with a product that already has more in it.
I asked my little nephew the other day if he knew what a calorie was and he quickly replied, “It’s what makes you fat.” I didn’t know if I wanted to laugh or cry. While he was technically correct and his response was unknowingly witty and oddly in tune, I also realized that I might have exposed him to too many pro cyclists and that a three year old shouldn't be concerned about his power to weight ratio. I tried to explain that calories don’t make you fat on their own, but eating more calories than you need can. He didn’t seem to really care about what I was saying so we went back to the more constructive task of tearing up pieces of paper for no particular reason.
Still, his answer got me thinking about whether any of us really understand calories. For whatever reason, one of the most commonly asked questions I get asked when I’m at a bike race is; “Hey Al, how many calories do these riders eat?” I’m so sick of hearing that question that my knee jerk response is always something dry like, “A lot more than you.” But, If I’m in a particularly good mood, I might slowly and critically look the person up and down, and respond in a matter of fact albeit facetious tone; “Obviously less than you.” That answer always seems to leave them even more confused.
So to set the record straight, let’s get some facts on the table:
1. A calorie is a unit of measure for energy just like a centimeter or an inch is a unit of measure for distance. Specifically, one calorie is the amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius, whereas 1 Calorie with an upper case “C” is equal to 1 kilocalorie or kcal (i.e., 1000 calories), which is equal to the energy needed to raise the temperature of 1 kilogram (1000 grams) of water 1 degree Celsius. In the United States, food is always represented using the upper case “Calories” instead of Kcals because smart people out there felt that Americans couldn’t handle using the “kilo” or “k” designation. That’s the equivalent to making “Grams” with an upper case “G” synonymous with “kilograms” or “kg.” Everyone else just uses “kcals” or “kilocalories.”
2. I’m not saying you’re fat and I’m very sorry for what I said earlier. Maybe we’re all just affected by misguided societal ideals. Know that if you just focus on your health and happiness the way you look is beautiful to me. In fact, I made you a Christina Aguilera iTunes mix. Listen to that first song because “You are beautiful, in every single way.”
3. Energy can take on many forms from the mechanical work done by a lever or machine, the heat given off by a fire, the radiation given off by a nuclear reactor, and even the sound of a tree falling in the woods that no one hears. In the end, energy is what allows us to exist, to move, and to be something other than a cold inanimate blob of silent nothingness.
4. Really, you’re not fat. Well, okay maybe you could lose a few pounds, but we could all lose a few pounds. We cool?
5. In effect, a calorie is a way to measure heat or the heat that something gives off when it’s burning. To measure the calories or energy in food, scientists literally put a measured quantity of that food in something called a bomb calorimeter and using a whole lot of pressure and oxygen, light a match to detonate that food. The heat given off by that explosion is measured in calories and everyone is happy because they got to blow something up in a lab (lab work is not always so exciting).
6. I’m not fat either. I’m just an athlete with extra (okay a lot of extra) fuel.
7. It’s convenient to represent the energy in food using calories (i.e., as the heat food gives off when we burn it), because when our bodies metabolize food we are literally “burning” that food to create heat, potential energy in the chemical bonds of adenosine triphosphate (ATP), and mechanical work when the ATP is broken. In addition, both processes require the use of oxygen. Thus, we can quantify energy by either measuring the heat given off by a chemical reaction or by the oxygen consumed in that reaction.
8. I said I was sorry.
9. A power meter like the CycleOps PowerTap measures mechanical energy or work by measuring the amount of physical force applied to the rear hub and the distance that hub travels or spins. Mechanical energy is measured in Joules, which is different than a calorie. One calorie is equal to 4.186 joules or roughly 4 joules per calorie. The human body, however, isn’t perfectly efficient, meaning only a fraction of the calories we burn while riding a bike gets turned into mechanical work or joules that moves the pedals. Most of those calories we burn are wasted as heat lost to the world. Specifically only about 1 out of every 4 calories we burn gets converted to joules or useful work. Since the conversion of joules to calories is roughly 4 joules to 1 calorie, the two cancel one another out, such that 1 joule of work measured by a power meter is roughly 1 calorie burned by the body. On a power meter, work is normally given in kilojoules or kj’s so 1000 kj’s of work is equal to about 1000 kilocalories or kcals which by US convention is equal to 1000 Calories (with an upper case “C”) of food. By measuring someone’s exact efficiency in the laboratory we can get a pretty good estimate of the calories they burn when riding with a power meter in the field. This is how we measure and know how many calories riders burn when they compete in races like the Tour of California. Long story short, if their power meter says they did about 3500 kilojoules or kjs, they’ve burned a little over 3500 Calories or kcals.
10. The CDC reports that 35.7 percent of Americans are obese. Obesity itself is closely associated with heart disease, stroke, type-2 diabetes, and certain types of cancer, making obesity the leading cause of preventable death. In 2008, the US spent $147 billion dollars on medial costs related to obesity and on average the medical costs for people who are obese are $1,429 higher than those who are normal weight. Those costs continue to climb.
11. A typical professional cyclist who weighs on average 154 lbs will burn 700 to 900 Calories per hour during a typical stage of the Tour of California. At 3 to 6 hours a day that’s a range between 2,100 to 5,400 Calories with an average day coming in at 3,500 Calories on the bike. Add an additional 2000 to 2500 Calories for daily living and resting metabolic rate and on average a pro-cyclist will consume between 5,000 to 7,000 Calories per day. An average person may only need 1,500 to 2,500 Calories per day to maintain a normal weight.
12. There are 3,500 Calories in 1 pound of fat. Just in case you were wondering.
My nephew, Kian, at 3 years years old, ripping his 12" mountain bike on the trails:
So far, every time I’ve gotten on a plane this year, I’ve flown to somewhere colder than where I was previously. I started the year in Los Angeles, leaving LAX at a nice balmy 70˚F, before heading back home to Colorado where temperatures were a cold but manageable 40˚F. Unfortunately, things started really getting tough when I headed out to spend the week in Verona, Wisconsin for the Cyclocross National Championships, where we brought the Skratch Lab’s kitchen trailer to cook for racers and spectators. I knew it was going to be cold heading out, but working in 20 to 30˚F temperatures all day was a harsh reminder of all of the challenges and risks associated with exercise and exposure in sub-freezing temperatures.
While I’ve spent a large part of my career thinking about how to improve performance in hot weather conditions, the reality is that humans are extremely well suited to cope with the heat. When it gets hot, we easily and effectively redirect blood flow to help dissipate heat to the skin, we sweat to help cool that skin, we make quick hormonal adaptations that increase our ability to hold and store water, and we become more efficient at this whole process the more we are exposed to the heat.
In stark contrast, humans have very few and fairly unsubstantial responses to the cold. Blood vessels can clamp down to help keep warm blood at the core, we might shiver to increase our metabolic rate, and for some individuals, after consistent exposure to the cold an increase in the core temp during exercise or an input of heat into the core can cause blood flow to increase to the hands and feet helping to keep the extremities warm despite the cold – something known as the “Hunter’s Reflex.” These responses, however, do little to actually keep us from losing precious body heat. Unlike some animals, our fur is limited and we can’t just burn fat to create heat, so our only real option for preventing hypothermia or other cold weather related injuries like frostbite or exercise-induced bronchoconstriction depends on our behavior and technology.
When we exercise in the cold, we might be creating extra heat, but the combination of sweat, movement, and an increased ventilation rate can create some real problems. Ironically, one of those problems is the loss of even more heat and the risk of getting too cold once we stop exercising because of excess moisture from sweat. In fact, Eric Larssen, who we supported on his recent attempt to ride to the South Pole, faced temperatures in Antarctica that were so cold that he had to find an exercise intensity that was just hard enough to keep his bicycle moving, but easy enough that he would minimize any sweat production or risk freezing when he stopped.
That extra heat production from exercise and the ease at which we can lose that heat in the cold also puts extra strain on our fuel stores. In particular, when exercising in the cold, we preferentially rely on carbohydrate in the form of stored glycogen. A lot of that is due to an increase in our fight or flight response – activation of our sympathetic nervous system that works in the background without conscious attention to keep us charging under stress. Cold as a basic stress causes our sympathetic nervous system to light up which can cause us to waste precious energy, especially carbohydrate, making it a lot easier to bonk or hit the wall in the cold. Despite having ample fat stores available to us, once we run out of carbohydrate, we risk becoming hypoglycemic (low blood sugar). Since our nervous system and brain rely solely on glucose (i.e., sugar or carbohydrate) we can get really loopy when that happens. While becoming hypoglycemic at any temperature is bad enough, becoming hypoglycemic and hypothermic can be even worse since in and of itself, hypothermia can also lead to a host of issues like confusion, apathy, irritability, and cardiac arrhythmias. Thus, making sure we have plenty of food available, especially simple sugar, can be a lifesaver when it’s cold or when we get cold.
This increase in sympathetic tone can also result in something known as cold diuresis. Essentially, when we’re cold or exposed to the cold we pee – a lot. As our sympathetic tone increases, it causes our blood vessels to stiffen which increases our blood pressure. At the same time, the cold causes blood vessels in our skin and periphery to constrict which drives more blood to our central blood volume further increasing blood pressure. This ultimately causes our kidneys to respond by pushing out dilute urine into our bladder and inadvertently dehydrating us even if we previously drank enough.
Another issue is that cold air is extremely dry air, which can damage our delicate lungs which function best when the air we breathe is brought up to 100% humidity and to body temperature (37.0˚C / 98.6˚F). This is easily done at warm temperatures, but at a given relative humidity, the colder the temperature the less water the air holds. As an example, at 100% relative humidity, there is 44% less water in the air from 0˚C compared to 10˚C (5 grams of water per liter of air versus 9 grams of water per liter of air). So when people say “it’s too cold to snow” it probably is too cold to snow since the air can’t hold the moisture. The net result is that as the temperature drops, we lose more water and heat through our lungs to humidify and heat the air we breathe. Specifically, depending upon the humidity, at 0˚C (32˚F), we can lose anywhere from 20-30% more water through our lungs compared to 20˚C (68˚F), and from 40-50% more water compared to when the temperature is at 30˚C (86˚F).
At rest, when our ventilation rate is only about 5 liters of air per minute, the amount of water we lose through our lungs is fairly insignificant - about 10.5 ml of water per hour at 0˚C and 6.5 ml of water per hour at 30˚C. But this small amount can become a really big deal when we are exercising and ventilation rates can be as high as 100 to 150 liters of air per minute. At a ventilation rate of 100 liters per minute, we can lose as much as 211 ml of water in an hour at 0˚C through our lungs versus 132 ml of water in an hour at 30˚C. This difference isn’t trivial since in many cases, our lungs can’t actually keep up with this differentially and the air we breathe isn’t fully brought up to temperature and humidity in the lower airways. This can lead to inflammation, damage to our airway structure, and a higher prevalence of exercise-induced bronchoconstriction and asthma in the cold winter season – something that can be worsened by dehydration or inadequate fluid replacement in the cold.
The question, however, is if all of this actually adds up to real dehydration in cold weather. While there are obvious risks of not getting adequate fuel and hydration in the cold and while there is a good rationale for how one might be at risk for becoming dehydrated in cold environments, there’s not too much research on hydration status in cold temperatures. This may be due to the fact that it’s not actually a problem and not something that we either worry about or study. But, that lack of attention may also be a problem in and of itself. In fact, in a recent study examining hydration status and sodium balance in a group of junior women’s soccer players in a cool environment, the players did not drink enough or consume enough sodium despite very low sweat rates (Gibson, et al. 2012). In another study, that examined water turnover and core temperature on Mt. Rainier, researchers found that hydration demands during the ascent in a group of seven novice climbers was elevated and that the climbers lost a significant amount of fluid despite not showing an elevation in core temperature (Hailes, et al. 2012). In both situations, dehydration occurred despite a lack of a heat stress and perhaps because of a lack of drive to drink due to the cold. Because, even a small amount of dehydration can hurt performance (Yoshida, et al. 2002), it stands to reason that staying focused on hydration, even in the winter, can help improve one’s performance.
With all of this in mind, it’s obviously important to first and foremost do everything you can to stay warm when temperatures are cold. For the most part, much of this comes down to our behavior – to being prepared and having the right gear if you’re planning to head out and exercise in the cold. Investing in the right clothing is obviously the first place to start – a high quality and tight wicking base next to the skin, an insulting wool over that, high loft materials for extra warmth as another layer of defense, and a final barrier to stop the wind on top. Add to that gloves, a good neck gaiter, something to cover your face and create a barrier to help maintain moisture lost through breathing, good head protection and booties to keep your feet warm. Also, instead of putting air activated toe and hand warmers around your feet and hands, try putting them next to your chest and see if that “Hunter’s Reflex” works for you.
Beyond the right clothing, it’s just as important to focus on your food and hydration in the winter as it is anytime of the year with some subtle differences. First and foremost, realize that your need for carbohydrate at any given intensity is probably going to be higher when it’s cold. So don’t forget to eat and to bring those simple sugars outdoors with you. Next, just because you may not sense that you are losing a lot of fluid or you may not feel that you need to drink, making sure you stay on top of your hydration, especially with something warm. It’s a lot easier to keep your core temperature up from the inside out than it is from the outside in, so having an insulated bottle and keeping some warm hydration product can be a small but significant thing. This is one of the main reasons we decided to develop our Apple and Cinnamon exercise hydration drink mix. We wanted something that would taste good hot and that would remind us to bring something hot out with us that had some calories and electrolytes in it for exercising in the cold.
Finally, use common sense. Sometimes it’s best to just stay indoors and go to the gym, get on a treadmill, or ride the trainer. Be smart out there and use your head. In cold weather, it’s really our best tool.
For more on the topic, check out the references below:
Gibson, J. C., Stuart-Hill, L. A., Pethick, W., & Gaul, C. A. (2012). Hydration status and fluid and sodium balance in elite Canadian junior women’s soccer players in a cool environment. Appl Physiol Nutr Metab, 37(5), 931-937.
Hailes, W. S., Cuddy, J. S., Slivka, D. S., Hansen, K., & Ruby, B. C. (2012). Water turnover and core temperature on Mount Rainier. Wilderness Environ Med, 23(3), 255-259.
Kippelen, P., Fitch, K. D., Anderson, S. D., Bougault, V., Boulet, L. P., Rundell, K. W. et al. (2012). Respiratory health of elite athletes - preventing airway injury: a critical review. Br J Sports Med, 46(7), 471-476.
Marek, E., Volke, J., Muckenhoff, K., Platen, P., & Marek, W. (2013). Exercise in cold air and hydrogen peroxide release in exhaled breath condensate. Adv Exp Med Biol, 756, 169-177.
McMahon, J. A., & Howe, A. (2012). Cold weather issues in sideline and event management. Curr Sports Med Rep, 11(3), 135-141.
Sue-Chu, M. (2012). Winter sports athletes: long-term effects of cold air exposure. Br J Sports Med, 46(6), 397-401.
Yoshida, T., Takanishi, T., Nakai, S., Yorimoto, A., & Morimoto, T. (2002). The critical level of water deficit causing a decrease in human exercise performance: a practical field study. Eur J Appl Physiol, 87(6), 529-534.
(2011). Update: cold weather injuries, U.S. Armed Forces, July 2006-June 2011. MSMR, 18(10), 14-18.