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Sudden involuntary and painful contraction of a tired muscle or a muscle group, cramp can appear during or after exercise. Several factors are often cited as being able to cause the appearance of cramps: accumulation of lactic acid or acid products from the muscle, mineral salts deficiency (Na, Mg, Ca, etc.) and/or vitamins (B1, B6, etc.), dehydration, great fatigue or a hot and humid atmosphere. Good hydration with a suitable drink and bicarbonate intake represent an aid in combating them.

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