Psoas major muscle

The psoas major is a large, powerful muscle that helps move the upper leg (femur) and the torso closer together in a flexion movement.

The psoas major muscle attaches on the lower spine (lumbar vertebrae) and passes in front of the hip-joint, underneath the inguinal ligament and to the top of the long thigh bone (the femur).

It forms part of a group of muscles called the hip flexors, whose action is primarily to lift the upper leg towards the body, when the body is fixed, or to pull the body towards the leg, when the leg is fixed.

It also plays a role in rotating the thigh at the hip.

Psoas Major Muscle

The Role of the Psoas Major in the Golf Swing

During the downswing, the obliques and psoas major are highly activated, creating a crunch-like position as your hips extend and your pelvis tilts (your belt buckle stays level, pointing forwards) while your chest remains over the ball.

The psoas major is an important part of your core, working to maintain posture, generate power, stabilise the body, and to decelerate the lower body for efficient energy transfer coming into impact.

Strengthening the psoas major is very important if you struggle with maintaining posture through the downswing and impact, especially with the longer clubs, where the greater length of the club’s shaft increases the forces that must be absorbed by the body.

Your hip flexors (including the psoas major) attach from your spine to your legs. When they are weak, they are not able to withstand the high forces of the longer clubs and are unable to hold your spine angle. This results in early extension (loss of spine angle) as the hip flexors lengthen under high loads, resulting in a loss of spinal posture before impact.