WATER, SODIUM, AND MUSCLE CRAMPS
Also called heat cramps, muscle cramps can occur at any time but are more common in longer events during hot weather. They are usually associated with dehydration and sodium loss, more often in athletes with reduced fitness and health. For example, those with adrenal dysfunction will often have low sodium levels and be less likely to regulate water efficiently, causing muscle cramps. Muscle imbalance and muscle fatigue can also be associated with muscle cramps during training and competition, with or without dehydration and sodium loss.
Regularly consuming sufficient amounts of water, along with sodium, can be very helpful to treat and prevent this type of cramping. However, potassium—traditionally suggested for muscle cramps—may be less helpful and can even be harmful in athletes whose sodium levels are very low. That’s because potassium levels in most of these athletes are already normal or too high.

 

 

Serious Heat Illness

 

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Heat exhaustion and heat stroke are two examples of severe illness in athletes. The problem more commonly occurs during competition in hot environments, where athletes are unable to regulate their body temperature, resulting in very high temperatures and dehydration (of over 3 percent body weight). Athletes typically complain of fatigue, lightheadedness, feeling hot (sometimes cold), stomach and muscle cramps, nausea, headache, and sometimes heart palpitations. In more severe cases, vomiting, diarrhea, hyperventilation, altered mental states, rapid heartbeat, and the inability to perform, or even to walk, can occur. The symptoms of heat stroke may also include confusion, amnesia, disorientation, visual disturbance, seizure, and even coma. Most of these signs and symptoms are due to the effects of dehydration on the brain and body.
Remaining hydrated, rehydrating quickly following hard training and competition, and maintaining proper overall fitness and health is the best remedy to avoid heat illness. Treatment requires medical attention, and often includes immediate submersion of the athlete’s trunk, legs, and arms into cool or iced water to reduce body temperature. If not available, the use of ice packs or ice water towels around the trunk, legs, and arms can also be helpful.
Regulating the consumption of water and electrolytes, especially sodium, should be a primary focus for all athletes. This goes beyond drinking enough water when working out or racing and includes maintaining high levels of aerobic function and overall health.

Small amounts of sodium, in the form of sodium chloride (salt), can be added to water throughout the event. In addition to replenishing sodium, this can increase stomach emptying to get more fluid and sodium (and carbohydrate when used) absorbed into the blood. This can include about 500 mg per hour, although this procedure, like all experimentation, should be tried during training to assure no intestinal distress is created.

The addition of sodium can especially be helpful in longer events of more than about four hours, or if you’ve just traveled to an event and have not had one to two weeks to acclimate to hot weather.

While water and sodium regulation may be more difficult in athletes who are physically larger (due to increased water loss), athletes who are older or very young may have similar problems. By their mid-sixties, for example, many athletes have less tolerance to heat stress. In addition, their heart rates are higher with less blood flow (cardiac output); and both their sweat mechanism and thirst regulation are less effective. These factors may be less significant in those who are healthier and fitter.

On rare occasions, it is possible for adrenal dysfunction to produce excess aldosterone, typically during the early stages of overtraining. This could potentially contribute to increased potassium loss, although this situation occurs infrequently.