[Malignant hyperthermia of effort or "heat stroke" (author's transl)].

Heat stroke following effort is not confined to hot regions. The authors have seen five cases in the Paris region between 1967 and 1974. It particularly affects young subjects, in pour training or living away from home. Clinically very similar to anaesthetic malignant hyperthermia, it has the same gravity, with a high mortality rate. It may be characterised by the triad: coma, muscular hypertonicity and hyperthermia of over 40 degrees C. Refrigeration, sedation and rehydration are all the more effective when started early. Improved knowledge of malignant hyperthermia of effort, within the more confused context of heat stroke, will ensure that it is recognised more frequently, limit its consequences and lead to better understanding of its underlying cause, the origin of which is undoubtedly muscular.