Most of the elbow crunching during push-ups is normal, and a small portion is caused by ligament laxity and uneven joint surfaces. 1. Physiological sound: when doing push-ups, all the weight of the body is concentrated in the elbow joint, the elbow joints are close together, and the cartilage of the joints rub against each other during the exercise process, giving out a crunching sound, which is normal, and it is recommended that you warm up before doing push-ups. 2. ligament laxity: push-ups elbow crunching can be considered elbow joint old trauma caused by ligament laxity of the elbow joint, do push-ups between the elbow joint and the joint friction increases, there is an abnormal ringing sound, may also be accompanied by pain and other symptoms. 3. Uneven joint surface: Uneven joint surface after elbow fracture can also lead to abnormal rattling of the elbow during push-ups, accompanied by pain, swelling and other discomforts. When the elbow crunches during push-ups and other symptoms such as pain occur, you should go to a regular hospital in time.