14-year-old boy if leg cramps, triggered by a lack of calcium and muscle strain, as follows: First, lack of calcium: 14-year-old boy in puberty, lack of calcium can easily lead to leg muscle spasms, contraction, thus causing leg cramps. Second, muscle strain: 14-year-old boy leg muscle strain, spasm, 14-year-old boy running, jumping activities are more, easy to lead to leg muscles, fascia repeated force pull, easy to cause spasm, contraction, rest will appear leg cramps. So 14-year-old boys in the emergence of leg cramps, daily life can eat more high-calcium and high-protein soy products, dairy products, lean meat, eggs, fish and shrimp and other foods, to promote the protein, calcium supplementation, if necessary, you can take oral calcium tablets and vitamin D to alleviate leg cramps. Avoid repeated squatting, running and jumping activities in your daily life, so as not to aggravate the burden on the fascia of the leg muscles, resulting in the recurrence of leg cramps.