Does the Golf Swing Have a Constant Radius?

Wed, 02/29/2012

The idea of a constant swing radius is a good model to help learn the the swing shape but it is not entirely true and can lead to really poor dynamics.


If we accept that the golf swing is primarily a circular motion then it would make sense to keep the club head on the very perimetre of that circle. This not only is a feature of creating power but is vital for ball striking consistency.
If the arms get drawn toward us at the top of the swing then they are no longer on the arc which means that they will have to be outstretched again to make contact with ball. This in/out movement creates excessive degrees of freedom to have to deal with mid downswing and inevitably leads to topped and fat shots.

Straight left arm
This topic is some what in line with golfers that try to “keep their left arm straight”. However, this is not the best way to think about your arc for a number of reasons.

  • Not everyone has the flexibility to keep the lead arm locked out. A really straight left arm would lead most golfers to becoming very tight and stiff in their movement
  • From a motor learning perspective, latest research suggests that we are far better off focusing on the affects/ intentions of our movement than focusing on the actual body segments. (see more on this in the research section.)
  • The left arm is only straight in the backswing, just after impact the right arm straightens/thrusts as the left folds away in towards the body. You really don’t want to be thinking about all of this at 100mph. Aim to keep your hands as wide as possible and the arms will look after themselves.

This is a video taken from the ‘Everyday Golf Coach’ app that explains the concept and demonstrates a great drill that will help you maintain your radius all the way around your swing while keeping a quiet focus.

Strong Dynamics Lead to a Narrowing of the Down Swing

In the downswing the legs are moving left and the hands will be pulled in towards the body somewhat. This has the affect of narrowing the arc in relation to the upswing. This is part of strong dynamics and should be encouraged. Should one try and swing down on an acr that mirrors the upswing then the movement sequence will be compromised and the arc will be too wide. The result is an out to in swing path and fat shots.

This is a screenshot taken from Everyday Golf Coach Power that indicates the upswing arc and downswing.

And here is Hogan demonstrating the same affect

For a more in depth understanding of swing dynamics see our dedicated coaching app;