Curl weight up slowly, pausing at the top and letting the weight down slowly in a controlled motion. Don't arch your back to help (cheat) with the lift. With a dumbbell, start with the weights at your side, palms inward; as you get halfway up the lift, supinate slowly so your palm is facing upward at the end of the lift to better contract the biceps.
• Alternate: Biceps Cable Exercise: A standing biceps curl with upper cable isolates your biceps nicely and helps develop you biceps "peak."
• Free weights can include dumbbells or barbells. Curls can also be done while standing on tubing.
• If you have lower back problems, try seated biceps curls with dumbbells.