Weakness of the legs when walking in the elderly is commonly due to the following reasons: 1, chronic diseases of the lumbar spine: for example, lumbar disc herniation, lumbar spinal stenosis, or even a compression fracture of the lumbar spine may affect the lumbar nerves to a certain extent, edema and chronic inflammation of the nerves, so that the nerve conduction function, especially motor conduction function is impaired, muscle loss of nerve nutrition and innervation, muscle atrophy, resulting in a decrease in strength, elderly patients in walking easily feel fatigue and weakness; 2, muscle trauma: due to weakened muscle strength, easy to injury, such as muscle strains leading to edema, elderly patients in walking will also appear muscle weakness and soreness, after rest and symptomatic treatment can gradually reduce; 3, degenerative atrophy: some elderly patients due to less participation in sports activities, long-term lack of exercise, the May make the leg muscles appear obvious degenerative atrophy, so that patients in the process of walking leg muscle weakness as well as soreness, usually pay attention to strengthen exercise, the symptoms can gradually disappear.