Proper hydration is essential to have dialed in for your performance and to practice throughout your training program. Rehydration is simply replacing the water lost in your body which occurs daily from sweating, respiration, gastrointestinal and renal losses. Replacing the fluid lost can be done through consuming water, fluids with added electrolytes and foods with a high-water content. Here are four hydration tips to add to your summer training program:
1) Know When You Are Dehydrated.
Feeling thirsty throughout during the day is the first sign of dehydration. Clinically, dehydration can be defined as losing 2-3% of your body weight after exercise. Signs and symptoms of mild dehydration include feeling dizzy, lightheaded, reduced cognitive function and performance and feeling thirsty. Severe dehydration is losing 6-10% of your body weight which can result in more drastic and alarming symptoms such as a decrease in cardiac output and sweat rate, low blood pressure, dark amber urine, dry mouth, confusion and in serious cases even death. Taking a detailed look at your own urine before and after exercising is an easy way to assess your own hydration. Aim for a pale, lemonade color. Another useful strategy is to weigh yourself after voiding before and after exercise to understand your own sweat loss and potential weight loss. Rehydration can be obtained with a strategy of 1.25 to 1.5 liters for every 1 kilogram body weight loss1. This should be consumed throughout the day and not in one sitting when working to rehydrate your body.
2) Consider factors that affect your hydration
Your body’s hydration is influenced by various factors such as your own body’s sweat rate, environmental stress, sweat sodium concentration, activity level and age. Sweat rate was discussed above but it is also important to remember, as a triathlete, that you should determine your sweat rate before and after swim, bike and run training sessions as sweat rate will likely be different for the three sports. Similarly, knowing if you are more of a saltier sweater when exercising can help support your hydration and supplemental electrolyte strategies. This can be done either with a simple sweat sodium concentration test at performance centers, such as eNRG Performance, or a non-formal test includes checking your face, body or clothing after training for white residue. The environment is another factor to consider that affects your hydration. The environment in which you are training, hot, humid or altitude, can also play a significant factor in your hydration and electrolyte plan. Lastly, don’t forget that as you get older, there is a greater risk for dehydration due to decreased body water. Taking the time this summer to frequently assess your own sweat rate in different environments can help enhance your performance and training through proper hydration. If you are able to have a sweat sodium concentration test done, even better as you will have more information relative to your individual needs.
3) Create a Hydration Strategy During Training
A proper hydration strategy should be unique to each athlete’s activity level, sweat rate and racing and training environment. Getting into the habit of weighing yourself before and after training throughout the summer as the environmental conditions differ. Pre-exercise hydration strategies include consuming 5 to 10 mL per kilogram of body weight about 2 to 4 hours before exercise. During exercise, maintain fluid consumption at a rate of 0.4 – 0.8 liters of water per hour1. Athletes with high sweat rates should consider adding electrolytes to their hydration strategy as this can help prevent dehydration and possibly be part of the multifactorial muscle cramping issue.
4) Understand Symptoms of Hyperhydration
Hyperhydration can lead to hyponatremia, or low blood sodium. Clinical hyponatremia is defined when the body’s sodium level falls below a sodium concentration of 130 mEq/L. This can easily occur through consuming too much fluid during a training session or during one sitting. Symptoms of hyponatremia include weight gain, bloating, nausea, vomiting, headache, confusion, respiratory distress and even death if left untreated. Your body works tirelessly to ensure homeostasis and autoregulation of the body’s temperature through sweating. Having a personalized hydration strategy for your specific training and racing environment can help prevent hyperhydration and hyponatremia.
Crafting a unique hydration strategy can power your performance and training. A good starting point of how much water athletes should consume per day is roughly half your body weight in fluid ounces of water. This is of course a generalization and needs to be specific to the athlete, activity level, age and environment. Remember hydration starts before exercise begins and there are many factors that can affect your own hydration throughout the day.
Lauren Mitchell is a Registered Sport Dietitian at eNRG Performance. She has a Master’s Degree in Nutritional Sciences with an emphasis in Sports Nutrition and Wellness. Contact her at firstname.lastname@example.org or www.enrgperformance.com .
(1) Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance. J Am Diet Assoc. 2000;100(12):1543‐1556. doi:10.1016/S0002-8223(00)00428-4.