Seventy-five percent of your body weight is water. We must maintain an adequate amount of water in our bodies to function properly. It becomes even more critical as the temperatures and humidity rises.

We lose water through the moisture in our breath, sweating, urinating and bowel movements. Also diabetes, diarrhea and vomiting can lead to dehydration. Diarrhea is the most common cause of severe dehydration.

Ten cups of water are lost per day by the average male. Electrolyte minerals such as sodium, potassium and calcium are also lost. If we do not replace our water and electrolytes as fast as we lose them, we will become dehydrated.

Thirst is the first symptom of dehydration. If you become thirsty you are already dehydrated. Try to maintain your water intake to avoid being thirsty.

Other symptoms are low blood pressure, irregular heartbeat, headache, nausea, muscle cramps, deep color urine and fatigue. More severe issues can arise if fluids are not replenished.

High school, collegiate and professional sports teams have strict rules on how much coaches can work their athletes in extreme temperatures. Several deaths have been reported after overexerting the body in the heat of the day.

My advice to anyone preparing for a race, playing a tennis match or a session of hot room yoga where the room my reach 100 degrees for up to 90 minutes is to drink enough fluids that you need to urinate just before you start.

This way you know you are well hydrated.

Your body can only absorb 24 to 32 ounces of fluid per hour. Therefore you cannot make up and recover from a large loss of fluids quickly.

Measure your sweat rate to determine how much water you have lost. Weigh yourself before and after your workout. Rehydrate yourself 16 ounces of fluids for every pound that you have lost. Do not try to lose weight by sweating. To lose weight, you want to lose fat not water.

I had two patients who had trained hard and qualified for an Ironman Triathlon. She was the better swimmer and cyclist, and he was the better runner. She beat him out of the water and finished the 112-mile bike ride ahead of him. At the 10-mile mark of the marathon, he passed her. He waited at the finish line for her.

Two hours later he found out she became disoriented on the race course and was taken to the hospital for IV- administered fluids. This was her first and last Ironman.

One of my high school runners went out too fast and hard at the Beach to Beacon race. She wanted to beat a fellow high school competitor. Her father told her to drink before the race because he knew it was going to be a hot day. She never made it past the five-mile mark before she could not continue due to dehydration.

I was playing in a local tennis tournament. I won my first two matches. In my third match I lost the first set and was winning the second when I noticed that my shirt was now dry and I was no longer sweating. The good news was my opponent was in worse shape and I held on for the victory.

Try to do your training in the morning before the heat of the day. If you have to exercise when it is hot, do not go all out and ease into your workouts. Drinking an icy slushy will allow you to last longer on a hot day.

Remember to hydrate before, during and after you exercise in the heat.


Dr. Robert Lynch is a former president of the Maine Chiropractic Association and head of the Lynch Chiropractic Arts Center in South Portland. “Staying in the Game” runs every other Thursday in the Press Herald.