By: Lisa E Heaton, MS, RD, CSSD and Meagan O’Connor, MS, RD, CSSD
When preparing a hydration strategy for an athlete competing in cold weather environments, the primary areas to focus on are euhydration and body temperature regulation. Many athletes will focus on staying warm but have little concern for hydration status because they may not feel or notice that they are sweating. It is important to help your athletes understand that when practicing or competing in a cool environment, their muscles are still generating heat and they are sweating, even if they cannot see it.
On the Field Hydration
Many factors may impact how much fluid a player will voluntarily drink during a practice or game in a cold environment (table 1). It is important to address and minimize the impact of these factors to support appropriate player hydration. In the cold, hypohydration of <3% body weight (BW) loss is unlikely to be detrimental to performance.1-3 That does not mean that your players can be careless with fluid replacement though, because if an athlete does lose 3% or more of their BW then their performance may become impaired.
Sweating rates may remain high in some players. Sweat rate will depend on exercise-induced heat production and how many layers of clothing a player wears to stay warm, as well as the permeability of that clothing.3,4 Clothing that is less permeable will trap sweat, impeding evaporation.4 Understanding the clothing your athlete will wear and his unique sweating rate in those cooler conditions can help to determine how much fluid he will need to maintain BW within 3%.
Other factors to consider are if the conditions are cold, windy and rainy. Wet clothing may increase the risk of hypothermia.3,4 In these conditions, it may be beneficial for the athlete to change out of wet clothing as soon as possible. The availability of warm fluids in this situation may be beneficial to promote warming.
All-Day Hydration
General Hydration
Regardless of the conditions that an athlete will be competing in, they want to come to the field in a euhydrated state. The player’s habits leading up to practices and games are just as important as his on-the-field hydration strategy. The simplest way for the athlete to assess if he is drinking adequately is to monitor urine color and volume. If urine is a dark yellow, then the athlete has not consumed enough fluid. Alternately, if the urine is clear and the athlete is using the bathroom frequently, he may be consuming too much too quickly. Encourage your athlete to have fluid readily available and to consume it throughout the day versus in large bolus doses. Table 2 provides practical tips to support all-day hydration.
| Table 1: Factors that May Increase Risk of Hypohydration When Playing in Cold Environments |
| Cold-induced diuresis |
| Impaired thirst sensation |
| Reduced desire to drink |
| Limited access to fluids |
| Self-restricted fluid intake to minimize urination |
| Sweat losses from over-dressing |
| Evaporation through respiration |
Hydration When Traveling
Staying hydrated during travel is very important for athletes, especially since travel days are when they have the chance to recover between games. Proper hydration should be included as part of the overall strategy to promote recovery and adaptation to travel because it may lessen the effects of jet lag.5,6 Dehydration may be detrimental to performance when flying across the country to compete. Encourage athletes to travel with an empty bottle so that they can fill it prior to the flight or bus ride. Opting for still water, sparkling water or 100% juice will be better options than
soda or alcoholic beverages. To help retain fluids, athletes should choose salty snacks such as pretzels, nuts or jerky while on the plane or bus. Consuming carbohydrate sources will also help the body to absorb fluids.
Key Take-aways
- Fluid losses from cold-induced diuresis and evaporation through respiration increase in cold weather – these may not be as visible to your athletes and the desire to drink is reduced
- Clothing worn for warmth to accommodate cold weather can impact evaporation of sweat
- Preparing for competition and all-day hydration is as important as in-game hydration
- Focus on travel hydration as part of the athlete’s recovery process/preparation for the next game
Conclusion
It is important for athletes to focus on hydration throughout the day and in all environments. By staying on top of hydration needs throughout the season, we can better help to prepare athletes to compete to the best of their ability.
| Table 2: Practical Tips to Promote All-Day Hydration |
| Carry a refillable bottle, try a 32oz bottle so that it doesn’t need to be refilled as frequently |
| Space fluids throughout the day, rather than large amounts in one sitting |
| Include fruits and vegetable in meals, they are made of a significant amount of water |
| Add salty foods to meals and snacks, especially after games or practices or when athletes are sweating |
| Include fruits or vegetables (cucumber is great) in water to add flavor |
| If an athlete prefers soda, encourage he try sparkling water |
References
- Meyer NL, Manore MM, Helle C. Nutrition for winter sports. Journal of Sports Sciences. 2011; 29(suppl 1): S127–136.
- Cheuvront SN, Ely BR, Wilber RL. Environment and Exercise. In: Maughan RJ, ed. Sports Nutrition, The Encyclopaedia of Sports Medicine, an IOC Medical Commission Publication, 1st edition. West Sussex, UK: John Wiley & Sons Ltd.; 2014: 425–438.
- Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine, Academy of Nutrition and Dietetics, Dietitians of Canada. Joint Position Statement: Nutrition and Athletic Performance. Med Sci Sport Exerc. 2016; 48(3):543-568.
- Sawka MN, Burke LM, Eichner ER, Maughan RJ, Montain SJ, Stachenfeld NS. ACSM Position Stand: Exercise and fluid replacement. Med Sci Sport Exerc. 2007; 39(2):377-390.
- Reilly T, Waterhouse J, Burke LM, Alonso JM. Nutrition for travel. J Sport Sci. 2007; 25 (suppl 1): S125-34.
- Samuels CT. Jet and travel fatigue: a comprehensive management plan for sports medicine physicians and high-performance support teams. Clin J Sport Med. 2012; 22(3):268-273.