Hydration strategy key as high school athletes begin practice

James Lang portrait

James Lang says coaches need to by proactive about hydration. Photo by Ryan Riley

AMES, Iowa – The first week of high school sports practices is a particularly vulnerable time for athletes, says an Iowa State University assistant professor of kinesiology. James Lang studies how environmental stresses, such as heat, affect how our bodies regulate internal temperature.

Lang says being proactive about hydration, rather than reactive, is important to keep athletes safe. He has the following recommendations for coaches and athletes:

Give athletes time to acclimate to the heat. Coaches should recognize not all athletes are prepared for the heat and humidity when practice begins, Lang said. It generally takes a week for our bodies to adapt, and heat acclimation is one of the most important preventative measure against heat illnesses. Lang suggests scheduling practice for early morning or evening and avoiding consecutive days of two-a-day practices during the first week. Football coaches should also limit pad use, opting for helmet-only for the first five days. Lang says proper hydration is essential to helping our bodies acclimate to the heat.

Hydration needs to begin before a workout. Most of us only drink water when we’re thirsty. Lang says that’s fine throughout the day, but he recommends athletes drink at least 16 ounces of water two or three hours prior to practice. Then 10 to 15 minutes before they begin, have another 8-ounce glass. Coaches should develop a hydration strategy for workouts, requiring athletes to take a water break versus simply making water available. Lang says thirst is not a good indicator of when to hydrate during practice.

“Athletes need to have a hydration plan and cannot rely upon thirst. They can suffer some of the ill effects of dehydration or heat exhaustion before feeling any indication of thirst,” he said. “Athletes losing 2 percent of their body weight in hydration are already performing at a deficit, and this may be borderline when they begin to feel thirsty.”

Lang has worked with college athletes and marathon runners for various studies and found dehydration to be a common problem. Even when athletes were given instruction to properly hydrate before coming into the lab, many tested at or near clinical dehydration, he said.

Measure weight to adequately replenish fluids after practice. Some athletes sweat more than others, which is why Lang recommends athletes weigh in before and after practice, as weight loss reflects sweat rate during a workout. In fact, anyone spending time in the garden or working outdoors in the heat should do the same. Lang says as a general rule, one should drink 16 ounces of fluid to make up for each pound lost.

“For harder workouts, it may be difficult to drink that back immediately, and it may take some time,” he said. “But having a big glass of water and eating salty snacks after practice is important.”

For intense workouts, a sports drink may be a good option to encourage more drinking while replenishing electrolytes, such as sodium.  

Be aware of the warning signs and take action. The warning signs of dehydration or heat exhaustion can be subtle or difficult to recognize, Lang said. Initial signs of dehydration may include a dull headache, dizziness or nausea. Symptoms that progress to goosebumps, severe headache and vomiting are all potential red flags for more severe heat illness. If players show any of these symptoms, they need to get fluids and go inside to a cool environment.

A common misconception with heat-related illnesses is that people stop sweating. Lang says this is not a good indicator. Athletes also may feel pressure to play through symptoms or limit what they drink during practice to prove their toughness.

“That is not the right mentality. Coaches really need to educate athletes about how to properly maintain hydration and the risks of not doing so. The best performing athlete will be properly hydrated.”

Everyone should be mindful of how they hydrate. These recommendations are beneficial for anyone who regularly exercises, especially in intense heat. Lang says heart rate increases when it’s hot in order to get more blood flowing to the skin to dissipate heat. For example, runners who use heart rate to measure workout intensity will reach their target heart rate at a slower pace on a hot day, and this will be exacerbated with dehydration.

Lang says it is harder for our bodies to regulate temperature as we age, which puts added strain on our cardiovascular system. This is important to keep in mind with exercise, but also with regular daily activities.