When a child is growing fast, because the body will secrete a lot of lactic acid or after a lot of exercise, the body will release lactic acid, it is likely to cause the symptoms of sore feet, which is a normal situation, no treatment, more rest, drink more water, promote the body’s metabolism can relieve the symptoms of sore feet. However, some children are infected by streptococcus, resulting in rheumatism, rheumatoid diseases and abnormal kidney metabolism of uric acid, it is likely to produce symptoms of sore feet, foot pain, which belongs to the pathological symptoms, to go to the hospital for further examination, you can test the rheumatism four, kidney function, for a clear diagnosis of the disease of sore feet is very good help. Usually also pay attention to the dietary improvement, eat more fruits and vegetables, and eat less particularly greasy, spicy, stimulating food is also conducive to the excretion of lactic acid.