Such as practice sit-ups incorrect posture or excessive force will cause physical hazards, the most common sit-ups on the body’s hazards is cervical spine damage, if excessive cervical force when doing sit-ups will lead to the cervical vertebrae of the second section of the forward protrusion, so it will lead to cervical nerve root compression, strain, which will occur in the upper arm pain, numbness, dizziness, head swelling, etc., all belong to the sit-ups way The way of sit-ups, incorrect methods, stretching and compression of the cervical spine and the resulting harm. Sit-ups if done incorrectly, and did not use the bilateral rectus abdominis, transverse abdominis and medial abdominal muscles, such as excessive application of the lumbar spine force will make the lumbar intervertebral disc protrusion, thus causing compression of the lumbar intervertebral disc, will cause the sciatic nerve and lower limb numbness, pain and other hazards.