For the causes of plantar cramps, the details are as follows: 1, calcium deficiency: calcium deficiency increases the excitability of the neuromuscular junction, often manifesting as hand and foot cramps, including, of course, plantar cramps. If an adult is deficient in calcium, it is manifested by the occurrence of calf gastrocnemius and plantar cramps at night. 2, injury to the plantar muscles, strain: for example, frequent weight-bearing activities or strenuous sports, such as going up and down stairs, hiking, walking with a burden, carrying a heavy schoolbag for a long distance on foot, can cause strain on the plantar muscles, resulting in inflammation of the plantar fascia, and protective Contraction, spasm, so there will also be the case of plantar cramps.