Avoid these muscle mistakes

Gaining strength is easy when you first start hitting the gym. "Your muscles go through a learning process, so almost anything you do triggers growth," says Mike Boyle, ATC. "But eventually your muscles adapt and improvements level off, and you have to train smarter to see results." Hit the refresh button by purging your fitness plan of these common pitfalls.

Mistake 1: You don't train your legs
Most guys' workouts are top-heavy. A sign of true fitness is a muscular backside. The largest muscles, including the glutes, are in your lower body. Training them releases hormones that build size and strength everywhere else. Try this: The elevated back-foot split squat. Hold a bar across your upper back using an overhand grip. Assume a staggered stance, with your left foot forward and your right foot back and on a six-inch step. Lower your body as far as you can and then push back up to the starting position. Do 10 reps, switch legs and repeat. That's one set; do three.

Mistake 2: You run too much
Logging km isn't a total waste of time, but it's close. This is because your body adapts quickly to repetitive movement, and that's running in a nutshell. Plus, running doesn't activate your fast twitch muscle fibres, which are great fat burners and body builders. Try this: Intervals-short bursts of intense activity followed by active rest. Set a treadmill to an eight per cent incline and run for 30 seconds. Then rest for one minute. Do this 10 times. This type of training leads to gains in aerobic and anaerobic performance that are significantly greater than with steady-state cardio, according to a recent Journal of Strength and Conditioning Research study.

Mistake: 3 You lift too slowly
Explosive lifting leads to fast gains. It activates more fast-twitch muscle fibres, which have the greatest growth potential. So lift like you mean it. You'll also crank up your heart rate, inadvertently increasing the number of calories you burn. Try this: Do the lifting phase of each exercise as fast as possible. (The actual speed doesn't matter. As long as the movement is explosive, your body will recruit fast-twitch fibres.) Then take at least two seconds to lower the weight.

Mistake 4: You stay in a comfort zone
Professional athletes don't sharpen their game simply by working on their strengths-they also eliminate weaknesses. So should you. Try this: Perform compound exercises (that is, moves that target multiple muscles), like deadlifts, chinups and dips. They're some of the toughest exercises you can do, and you can't make serious gains without them. Boost your results with the instant exercise upgrade on this page.