With the extreme temperatures experienced in the summer months, heat stress injuries are a serious threat. This threat increases when you exercise. Many heat injuries occur during the hottest periods of the day, during periods of physical stress, to personnel who are either not acclimated or just recently acclimated. In spite of water being consumed the injury occurred. That could be because the individual did not consume enough water.
It is important to consume water prior to and during exercising. The chart above was borrowed from Fort Jackson and in my opinion, no one does heat injury prevention better than the U.S. Army. When the temperature is between 78 and 81.9 there is no limit on the amount of easy workout a person can do as long as they consume a ½ quart of water per hour. When the temperature goes above 90 degrees then the person should rest 10 minutes after every 50 minutes of easy workout and consume 1 quart of water per hour.
As with all things, this must be done in moderation. Many people who are exercising are trying to lose weight or might be skipping meals to stay fit. The body needs a balanced diet with all the minerals and nutrients to stay healthy. If one skips meals or doesn’t consume the right diet too much water can be harmful. Too much water can cause a condition known as Hyponatremia or what many refer to as “water intoxication”. The definition of Hyponatremia is a less than normal concentration of sodium in the blood, caused by inadequate excretion of water or by excessive water in the circulating bloodstream. In severe cases, the person may develop confusion and lethargy, leading to muscle excitability, convulsions, coma and possible death. The symptoms may mimic heat exhaustion.
- So what can one do to keep hydrated and prevent Hyponatremia? Here are a couple of ideas:
- Consume no more than 1 1/4 quarts of fluid per hour
- Daily fluid intake should not exceed 12 quarts per training day
- Provide electrolyte replacement drinks if possible at meals
Remember to keep track of the number of quarts consumed per hour by using a marker to put a check on the arm.
- To prevent heat injuries while exercising it is important to:
- Assess the risk daily and review it as conditions change.
- Watch the temperature closely and exercise accordingly.
- Know the signs and symptoms of heat stress injuries, use the buddy system, and raise concerns to your buddy.
- Risk can be reduced when one is acclimated to the temperature and weather conditions of the area.
- Ensure that a normal diet is eaten each day and know that drinking too much water can result in harm.