How can you treat or prevent cramps?

Muscle cramps during exercise can drastically affect performance and are a common problem amongst endurance athletes. These cramps are common during or after exercise and can range from a minor cramp in a small muscle that passes quickly on its own, to a very painful cramp in a large muscle that remains causing pain for hours. The causes of cramps are not fully understood, but there are a few of causes that have been identified (see What causes muscle cramps in exercise?’).

How to prevent muscle cramps?


One of the suggested causes of muscle cramps is electrolyte imbalance. This would occur as a result of mostly sodium losses in sweat. There is no question that electrolytes are needed for normal function of muscles and are used in the process of contraction and relaxation of muscles. Therefore, it is tempting to think that depleting these electrolytes could result in disrupted and uncontrolled muscle contraction (i.e. cramping). Having said that it is surprising that we have extremely limited evidence that this is actually the case and the only studies that are always referred to are very old studies in mineworkers who worked long days in very hot mines.

We have extremely limited evidence that depleting electrolytes could result in disrupted and uncontrolled muscle contraction (i.e. cramping)

Nevertheless, the risk of cramping may be reduced by maintaining a good electrolyte balance, which can be achieved through consuming electrolytes during exercise (most notably sodium). Trying to match the amount of electrolytes lost in sweat with the amount ingested is not necessary, but avoiding large losses at the end of exercise is recommended. What very large is, is not exactly known but a loss of 5 grams of sodium is unlikely to be a problem and this is a very large loss.

Training specificity will be crucial in the prevention of muscle cramps

Electrolyte imbalances are probably only explaining a small percentage of cases of muscle cramping. Poor conditioning of the muscle is far more important. Training specificity will be crucial in the prevention, both in terms of exercise duration and intensity. Because competition is usually just a little more intense and just a little more effort than the hardest training sessions, cramps are more likely to occur in this situation. Also, changing position on a bike, for example, may change recruitment patterns and will engage previously "less trained" muscles. This can increase the risk of cramps, at least anecdotally.