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Many make judgment errors when lifting weights. Men are more likely to lift weights that are too heavy for them, while women tend to be fearful of bulking up and go for weights that are too light. But a recent study found you don’t need heavy weights to gain muscle — lighter weights can be just as effective if used correctly.

Danberg recommends choosing a weight that you can lift 30 times to start but afterward can lift only 15 times more. “You want to get to your repetition goal but be able to put down the weight and think, What’s next? You don’t want to feel exhausted to the point of ‘Oh, God, what did I do?’ ” says Danberg. “This will keep you injury free, but you will still feel the burn.”

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When it comes down to it, it’s all about maintaining correct form to get the most out of resistance training. “When you have incorrect form, chances are you are going to jeopardize your balance. You work your body harder than it actually has to work,” says Danberg.

Maintaining good form while lifting will also improve your overall posture. “Generally, people who don’t have good posture have tight or weak muscles,” says Danberg. “If you do not think about your form while you are lifting, you are training poor posture.”

Quick tips for correct form: keep a strong upper back, with your chin and chest up, and tighten your core.

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There’s nothing wrong with taking it slow, says Haley. A lot of exercises become more challenging when they’re slowed down. “Try lowering your arms slower when doing a bicep curl,” she says. “Using your full range of motion is sometimes harder because you need to use all your muscles to do it all the way.”

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