It doesn't matter how much you can lift or how long you've been lifting—one bad move can still land you on the disabled list. "Some of the most popular exercises out there are also among the most dangerous and ineffective," says Mike Boyle, A.T.C., owner of Mike Boyle Strength and conditioning in Woburn, Massachusetts.
Purge these body breakers from your routine before they stall your progress—or send you to the sidelines. (Plus: Is your workout burning flab—or just burning up your time? Don't fall for these 5 Fat-Loss Myths.)
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DITCH IT: Kipping Pullup
This move adds momentum-generating hip thrusts to the standard pullup and is a favorite of extreme-workout programs. It's also good for guys who struggle with the classic exercise. "It's a simple way to do more reps," says Boyle, "but each one violently pulls your shoulder joints, which are among the most delicate in your body."
DO IT: Chinup
Most men are able to complete more chinups than pullups—that's because the underhand grip allows the biceps to participate more in the exercise. Grab a chinup bar using a shoulder-width, underhand grip, and hang at arm's length. Cross your ankles behind you. Pull your chest to the bar, pause, and return to a dead hang with your arms fully extended.
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More: Take the Chinup Challenge
DITCH IT: 45-Degree Leg Press
"This exercise forces your back into a rounded position and compresses your spine," says Craig Ballantyne, C.T.T., author of Turbulence Training. "That can cause a herniated disk." Plus, the move doesn't engage your core or stabilizing muscles, so any gains from it won't translate well beyond the gym.
DO IT: Dumbbell Bulgarian Split Squat
"This exercise is much closer to real-world movements," says Ballantyne, "and it hits your core and tests your balance." Holding a pair of dumbbells at arm's length next to your sides (palms in), place the top of one foot on a bench behind you. Lower your body as far as you can. Pause, and return to the starting position. Do the same number of reps on each side.