Cramps is the painful involuntary contraction of a muscle or muscles of the body and is generally caused due to strain or muscle fatigue. Symptoms Cramps are generally observed in some specific muscle groups such as the calves,the hamstrings,quadriceps and the abdominals. Root causes Cramps are caused due to the losing of salts by the body.This commonly takes place during rigorous exercising in extreme heat and is also a sign of poor flexibility of the body.