Rehabilitation Services

Newspaper Column

With the temperatures hovering in the mid to high nineties everyone who works out in the heat or is active outside needs to watch out for signs of dehydration and maintain proper hydration.

Dehydration normally occurs when one doesn’t drink enough fluid to replace what is lost through sweating. Sweat secretion and sweat evaporation are the body’s primary ways of dissipating heat to avoid dangerous and sometimes deadly internal temperatures. Without proper fluid intake one may experience one or more of the signs of dehydration such as thirst, fatigue, headaches, weakness, and nausea. One quick sign of dehydration can be urine that is excessively dark; urine color in a well-hydrated person should be clear or pale yellow.

During extreme temperatures or intense physical activity, dehydration can occur in as few as 15 minutes. The American College of Sports Medicine (ACSM) recommends that individuals pre-hydrate with about 16 oz. of fluid 2 hours before exercising. This will ensure better hydration and allow time to urinate off any excess fluid before the activity. Once exercise is started, early intake, within the first 15 minutes, of cooled fluid is encouraged. Drinking fluid once dehydration has begun, within 15 minutes in extreme conditions, can lead to stomach cramps and aches. Every person has individual fluid needs based on their fitness level, their body size, and the activity they are doing. In general it is recommended that an athlete drink between 6-8 oz. of fluid every 20 minutes.

For activities lasting less than 1 hour, water is a good fluid choice. However, for intense activities or activities lasting over 1 hour the ACSM states that flavored sports drinks with electrolytes and carbohydrates are better fluid choices. Sports drinks containing 4%-6% of carbohydrates (such as Gatorade) have been shown to delay fatigue, increase voluntary fluid intake and even enhance some athletic performances while being absorbed faster than pure water. Sports drinks with more than a 6% carbohydrate mixture and soft drinks are not recommended for fluid replacement immediately before, during or after strenuous activities.

Children involved with sports or outdoor activities are especially susceptible to dehydration and heat related problems. Children absorb more heat faster from the environment than adults do; they can not dissipate heat through sweating as efficiently as adults; and some children do not remember to drink enough fluids to replenish those lost.

The National Athletic Trainer’s Association recommends that children pre-hydrate before intense or outside activities one hour beforehand. During activities, children weighing less than 90 pounds need to drink from 3-5 oz. every 20 minutes and up to 6-9 oz. every 20 minutes for those weighing over 90 pounds. Other ways to beat the heat are to dress kids in light colored, loose fitting clothes; make sure kids have fluids in hand when they are sent outside or to games; keep their fluids cooler than the air temperature; and try to make sure there is plenty of shade during rest breaks.

Final Tips for good hydration with activities:

1. Pre-hydrate 2 hours before the activity.
2. Start drinking early into the activity, 15-20 minutes.
3. Have a cooled drink that you like on hand.
4. With intense activities or activities lasting over an hour drink a sports drink with 5% to 6% carbohydrates.
5. During the activity drink from 6-10 oz. of fluid every 20 minutes.

Ann Gasper, Rehab Marketing Coordinator, compiled this article from information provided by therapy staff at HSC Rehabilitation Center, which is located on the first floor of HSC Medical Center.