Cramps are also known as muscle spasms, which often occur, and are mainly considered to be related to muscle fatigue, cold stimuli, and disease factors. 1. Muscle fatigue: Unreasonable exertion, movements that are more difficult than the body’s ability, and attempting new and unaccustomed movements can all lead to muscle fatigue, resulting in a decrease in movement coordination and triggering muscle spasms. 2. Cold stimulation: the cold environment will lead to increased muscle excitability, prompting muscle tonic contraction. 3. Disease diet: high fever, calcium deficiency, tetanus, epilepsy and other diseases, can also trigger this symptom. Frequent occurrence of this symptom, should cause the patient’s attention, as soon as possible to the medical examination, to be targeted treatment.