Cramps are another villain to myths and confusion. Research provides few answers on what causes them and how to prevent them. Cramps can range from a slight twinge to excruciating pain, and may last for a few seconds to several minutes of time.
Cramps are the involuntary contraction of the muscle, but the mechanism behind this abnormal stimulation is unknown. The most convincing is that a high training workload or poor fitness in the muscle increases cramping, whilst poor stretching may also contribute. We know that some electrolytes are involved in muscle contraction however besides sodium, loss of electrolytes such as magnesium and calcium from sweating is minimal and little evidence supports dehydration or loss of electrolytes as a cause of cramps.
So you’re best bet is to allow adequate rest, stretching and recovery from exercise, be careful not to increase intensity towards the end of a long session when muscles may be fatigued. And although the evidence is weak, staying hydrated before, during and after exercise may help or at the very least provide other health and performance benefits.
VIS Sports Dietitian, Kylie Andrew