why do my knees crack when i squat

The cracking sound in your knees when you squat is usually due to a normal phenomenon called crepitus. This happens when the surfaces within your knee joint, such as cartilage and surrounding soft tissues, rub against each other or when small gas bubbles in the joint fluid pop during movement. It is common and generally harmless if there is no accompanying pain, swelling, or stiffness. As people age, natural changes like cartilage wear can make the joint surfaces less smooth, which can increase these cracking or popping noises. Other causes include tendons or ligaments snapping over bony prominences around the knee. However, if knee cracking comes with pain, swelling, locking, or a grinding sensation, it may indicate a more serious issue such as cartilage injury or osteoarthritis and warrants a medical evaluation. In summary, knee cracking when squatting is common and not usually a cause for concern unless it is painful or accompanied by other symptoms.