EAMC are are a common experienced condition experienced by athletes in every sport. There´s currently no scientific prove for the cause that is widely accepted. Theories for the cause relate to observational studies rather than sound experimental scientific evidence. That´s why treatment methods vary in terms of their effect and prevention strategies remain on luck which makes it hard to find the ultimate prevention strategies and it´s also a reason why these strategies remain unsuccessful.
As we looked on dehydration as a potential cause in the first article we´ll focus on heat as an influential factor and the science behind it.
If it´s not the fluid loss through heat, is it perhaps the heat itself that leads to the muscle cramps? The scientists are also following this trail. And indeed a picture emerges here: Many athletes complain of spasms, especially in competitions under hot and humid conditions. Martin Schwellnus of the University of Cape Town states the following:
"It is well documented that there are a number of mechanisms by which exercise in the heat will result in the development of muscle fatigue, independent of electrolyte depletion or dehydration."
In conclusion, heat has an inﬂuence on the neuromuscular control of the peripheral and central nervous system but this does not result in a greater occurrence of EAMC. However, more EAMC will occur due to increasing muscle fatigue, which causes a change in neuromuscular control due to a hot outside temperature.
The ﬁrst suggested prevention method for cramps is the consumption of salt and ﬂuid. People working in an industrial setting in a high temperature were given a saline solution orally and this prevented cramps to occur. This same prevention strategy is applied during tennis in the heat and it is recommended by the National Athletic Trainers’ Association to be well hydrated before exercise to avoid cramps. However a recent study shows that the total amount and rate of sodium intake during an ultramarathon in a hot environment is not related to muscle cramping, dehydration or hyponatremia.
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