The prime mover of hip extension is the gluteus maximus muscle.
The gluteus maximus is the largest muscle in the hip and is primarily responsible for the extension of the hip joint. This movement is crucial in various activities such as walking, running, and climbing stairs. When the leg moves backwards, the gluteus maximus contracts to pull the thigh down and back, effectively extending the hip.
In addition to the gluteus maximus, other muscles such as the hamstrings contribute to hip extension, but the gluteus maximus is considered the most powerful and significant muscle for this action. Strengthening the gluteus maximus is important for athletic performance and overall functional movement.