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A rotary golf swing is basically a one plane swing. It gives more consistent results as the club head swings on just one plane, that is one angle, around you so there is less to go wrong than if you swing on two planes.

To make a rotary golf swing, you need to turn your body around a fixed spine angle. Address the golf ball and then stand straight up with your spine. Tilt forward from your hips about 40 degrees and take your stance up so that your feet are shoulder width apart. Begin your back swing by rotating your shoulders to the right, if you are a right handed golfer, and maintain your forward spine tilt throughout your swing. Your arms will remain low as your shoulder turn pulls the club head on to the inside. Continue to turn and as you reach the top of your back swing, your left arm should be in line with your shoulder plane. Ensure that your left arm is at the same angle to the ground as your shoulders are.

To begin the down swing of a rotary golf swing, you now need to turn the left side of your body towards the target. Your arm movement is very passive and your body should keep turning constantly through impact and into your follow through. Your body turn should lead the club head back to the golf ball on the same path that it was moved away from the ball on. Your right forearm will be on plane at around hip high before impact, with your left forearm very much on the inside. As you swing through impact and into the follow through position with a rotary golf swing, you cannot turn enough. The club will move back on to the inside of the target line very quickly and the body will continue to rotate hard until the shoulders finish aiming very left of the target.

If you are very arms dominant in your golf swing, then you are using your arms much more than you are using your body as you swing. As a result, you will be lifting the golf club up and away from the golf ball rather than making a rotary action in your body and this will produce a less powerful golf swing.

A rotary swing involves your body rotating around your spine to produce power. As you swing through impact, your torso should be rotating towards the target with very little rotation in your arms and hands to square the club face to the target. If your hands turn over through impact, then the club face will close and the ball will be struck to the left of the target.

A rotary golf swing is a very powerful movement. By using the larger muscles of your torso as well as the smaller ones, you generate maximum club head speed through impact and you will produce your longest golf shots.