There are many reasons for leg pain in teenagers, and the common ones are as follows. First of all, it may be the pain caused by the accumulation of too much lactic acid in the legs due to excessive exercise and lack of good rest. If this is the case, you should pay more attention to rest after exercise, and you can relieve the pain by soaking your feet. It may also be caused by the lack of calcium. Teenagers are in a period of vigorous growth, and the growth of skeletal muscles requires calcium, so the amount of calcium needed is relatively large. If the amount of calcium ingested at this time is insufficient, leg pain will occur. If it is caused by calcium deficiency, the intake of calcium should also be increased, and more sun exposure and exercise should be done to promote the absorption and transformation of calcium.