One of those common driving range tips I hear all the time while eve’s dropping on amateur golf lessons is to “keep your left are straight.” Now while I am a proponent of this move and teach it to many students myself, it is important to note that not everyone should or can keep their left arm perfectly straight through their back swing and impact. So why should your left arm be straight?
The left arm being straight in your backswing allows you to do two things. First, it allows you to maintain connection with your body. New players like Dustin Johnson and older players like Ben Hogan get their left arm perfectly across their shoulders in the backswing, then all they have to do is rotate back to the golf ball.
(HOGAN & DJ with their connected straight left arms)
Second, having straight left arm in the backswing creates width, and width in the backswing allows us to maintain “connection” and generate speed. Simply put, width is the ability to get our hands away from our head and body.
Last, it’s one less moving part. When the left arm bends in the backswing, it becomes a lever and although it can help generate extra power, it’s release back to impact needs to be timed perfectly to be effective.
Ok, so it sounds like you always want a straight left arm, right? Not so fast… Tour pros (most of them) are build to get in perfect positions, but most of us, are not. There are a few physical limitations which can keep us from properly getting in this position.
- A tight upper back – also known as the thorasic spine, if the mobility here is limited it will cause a lack of rotation in the back swing, which will limit the upper body and lower body separation. If this is the case. To compensate for the lack of rotation in the upper body, the left arm will bend at the elbow to help get the club back.
- Shoulder issues – A lot of my students tend to have very tight shoulders. This is a direct cause from sitting at a desk and hunching over a keyboard for 40 hours every week. When the shoulders round and close off the blade, it doesn’t allow for the right arm to rotate past your spine. A short and acute angle in the right arm will almost always lead to a bent left arm in the back swing.
(JB Holmes has a short rotation and bends his left arm… he is not lacking for distance.)
In any case, make sure that the move is correct for you, not for someone else. You can do some simple range of motion tests or come out and see your local PGA Pro for some help!