The athletes playing football in this extreme heat, especially if there is a two-a-day practice sessions, must think seriously about prehydration. Coaches, captain, and parents must encourage the player to increase fluids and be well hydrated by drinking before, during, and again after practices.

The athlete who begins exercise with less than normal amount of body fluid runs the risk of adverse reactions to the cardiovascular system, body temperature regulation, and performance during the practice or game.

Athletes playing football can lose as much as 10 quarts of fluid during the sweat rate each day. Large losses of sodium and chloride occur when one sweats. These must be replaced during the practice sessions from day to day.

The athletes should begin their strength training exercise conditioning before going out for the pre-season practices. This helps them to become acclimated to warm weather. If one begins to exercise dehydrated, this will create the risk of heat illness and poor performance.

The athlete should get into a habit of drinking at least 160z of fluid in the evening before retiring and another 160z upon awaking in the a.m. to maintain fluid balance.

It is important to drink 160z-320z one hour before and another 160z about 20 minutes before the training sessions start. One may get into a method of weighing oneself before and after exercise to make sure one has taken enough fluid to prevent dehydration.

At times, with heavy sweating, fluids that contain carbohydrate and small amounts of sodium chloride will be helpful in fluid and mineral replacement during the practices or competition.

If the athlete has the slightest sign of thirst, this is a warning sign of dehydration and possible heat illness. Drink at least 80z every 15 minutes to replace fluid loss and 240z - 360z for every l lb of body weight loss after exercise.

Dr. Robert F. Weiss, a sports podiatrist, was a member of the Medical Advisory Committee of the 1984 and 1988 Olympic Marathon Trials. Weiss is a veteran of 35 Marathon & has a practice in Darien; affiliated with Stamford Hospital and member of Stamford Health Medical Group-Foot & Ankle. For info visit his Web site at www.stamford, and find a Physician-Dr. Robert F. Weiss.