Few things are as painful as muscle cramps, which can occur at the most inopportune times. Just ask the tennis pro whose leg cramp causes him to lose a match, or the runner, cyclist or swimmer who can’t finish a race because of one, or the dancer who has a cramp during a performance. Usually the affected muscle is in the calf, foot or thigh (hamstrings or quadriceps). Note: Cramps that strike when you’re at rest, such as nocturnal leg cramps, have nothing to do with exercise and are not discussed here.
A cramp starts when the muscle is shortened—with your calf, for example, that occurs when you point the foot downward. Despite decades of research, exercise cramps remain a mystery. It used to be thought that they were caused by low levels of electrolytes in the blood (minerals such as calcium, sodium and potassium, which help regulate blood pressure and fluid balance), resulting from dehydration and heavy sweating. Thus, drinking lots of water or sports drinks has often been advised as a preventive.
But it turns out that there’s no solid evidence for any of this. In fact, several studies have found that people with cramps are not more likely to be dehydrated or low on electrolytes than those without cramps.
The prevailing theory now is that cramps are caused by plain old muscle fatigue. Being less-than-adequately fit and working out too intensely appear to increase the risk. Certain medications and medical conditions, including atherosclerosis (hardening of the arteries), also make cramps more likely. But much remains unknown, and exercise physiologists still can’t explain why some athletes are more prone to cramping than others.
How to prevent cramps
Proper training is the key to reducing the risk of exercise cramps—general endurance training as well as training specific to your sport or activity. When increasing the intensity of your workouts, do so gradually. Including plyometric exercises—basically, those that involve jumping or other explosive muscle contractions—may help.
How to stop a cramp
- Stretch the affected muscle. For a calf cramp, for instance, flex your foot upward. You can grab and pull the toes and ball of your foot to help flex it. Walking may help relieve a calf cramp, particularly if you put your full weight on your heels.
- Massage the muscle; it may hurt, but persevere.
- The stretch shown below can help relieve a calf cramp. Done regularly, it may also help prevent calf cramps.
Lean with your forearms against a wall and your feet perpendicular to it. Step back with the leg you want to stretch, keeping the front foot in place. Slowly bend your front knee until you feel a stretch in the rear leg, keeping the rear knee straight and heel on floor;