The following scenario will probably feel familiar to a lot of recreational golfers…
You’re standing over the golf ball, preparing to hit a shot. Then, the very first move you make in your backswing is a retraction. Your trail arm withdraws, kinda like you’re about to elbow a pickpocket that’s trying to steal your wallet from your back right pocket. We don’t want that. Try this drill with your PlaneMate band to gain awareness in your arms.
Wrap the long green band around your upper back and connect both sides to an aim stick. The aim stick should comfortably rest across your lower pecs.
Take a few slow speed swings. If you artificially try to retract your trail arm in your backswing your arm will hit the stick. Focus on rotating your body as you elevate your arms. Once you get the hang of it you can start to ramp up your speed.