Avoiding these common shoulder training mistakes will keep you injury free and on the road to building cannonball-sized delts!

#1: Going Very Heavy With Behind-the-Neck Presses

Going heavy with your presses isn’t a mistake. That’s how you build size and strength in your shoulders. But when you’re using max weights for very low reps, stick with presses in which you lower the bar to the front of your head. Amateur bodybuilder and sports-medicine doctor Guillermo Escalante, Dsc, CSCS warns: “When you lower the bar, the deltoids are lengthening to a fully stretched position, but they’re also at their weakest.

The highest risk of injury in any sport occurs when the shoulder is abducted and externally rotated. Loading up a huge amount of weight is just asking for a tear.” Although the joints of some younger bodybuilders may be more resilient, for many others the risk is real. Keep your weights moderate if you’re doing behind-the-neck presses.

#2: Straightening Your Arm on Lateral Raises

Lateral raises targeting the middle delt are done with a slight bend in the elbow. The problem arises when the elbow isn’t locked throughout the movement. Too often you see guys with a 90-degree bend at the bottom, but their arm straightens to 180 degrees at the top, especially when they do one arm at a time. Straightening the arm is called elbow extension, and the triceps — not the debts — is responsible for this action. You can’t open and close the elbow joint during execution. Keep it locked in a slightly bent position.