There are many reasons for muscle pain and weakness in both arms and legs, including excessive whole-body exercise, peripheral neuritis and cervical spondylosis. 1. Excessive whole-body exercise: If you don’t exercise for a long time and occasionally perform intense whole-body exercise such as calisthenics, it will easily cause the accumulation of lactic acid in the whole body, which will lead to the appearance of generalized muscle soreness, pain, weakness and other manifestations. 2. Peripheral neuritis: also known as multiple peripheral neuritis, mainly due to poisoning, nutritional deficiencies, metabolic disorders, inflammation, autoimmune diseases and other factors, caused by peripheral nerve damage. Common symptoms are symmetrical numbness, pain, abnormal sensation and muscle weakness at the ends of limbs. 3. Cervical spondylosis: such as cervical degenerative changes caused by local tissue hyperplasia or spinal canal stenosis, resulting in spinal nerve compression or injury. If the nerves innervating the upper and lower limbs are compressed, bilateral leg and arm pain and weakness may occur. In addition to the above causes, trauma (e.g., impact, falling, stumbling) and cerebrovascular disease (e.g., cerebral hemorrhage) may also present the above manifestations. If the above symptoms do not improve, it is recommended to go to the hospital, complete the relevant examinations, identify the cause of the disease, and under the guidance of the doctor, give targeted treatment.