The main hazard of sit-ups is that exercisers who exercise unreasonably, resulting in increased likelihood of cervical spondylosis or lumbar disc herniation, often due to inaccurate exercise posture. 1. Cervical spondylosis: in fact, normal people sit-up exercise, often due to incorrect force or exercise too fierce and other reasons and the cervical spine caused great pressure, in the long run may lead to cervical spine damage and then induced cervical spondylosis. 2. Lumbar disc herniation: Lumbar disc herniation is also one of the possible hazards of long-term sit-ups. Completion of sit-ups often requires excessive bending of the lumbar spine, and if the exercise force is too large and too fierce, it may lead to lumbar disc herniation. It is recommended to pay attention to the correct posture in the daily sit-up exercise, and should control the exercise intensity and exercise time, to achieve a combination of work and rest, do not blindly training.