The pushup is a classic exercise that you learned in middle school. But for that same reason, you've probably picked up some bad habits throughout the years. "Your technique is just as important when doing a pushup as it is when you're doing a heavy lift," says Doug Nepodal, co-owner of Classic Iron Kettlebells in Ventura, California. "If you want to increase your gains, you've got to keep perfecting your technique." Here's how to clean up your pushups, and crank out more reps today. (We found 3 simple tricks to perfect your form and protect your shoulders: The Best Way to Do Pushups.)

The Mistake: You only concentrate on the push.

The move is called the pushup, but that doesn't mean you can ignore the descent. "Don't let gravity do the work for you," says Nepodal. "The eccentric, or lowering, portion of the move builds strength, too."

The Fix: At the top of the pushup, pretend to dig your hands into the floor by grabbing it with all of your fingers. This turns on your lats, which you'll use to pull your chest toward the floor. Your lats are the biggest muscles in your back, so activating them not only helps with lowering, but also helps when it's time to power up to top, says Nepodal. (Think you have the pushup down? Think again. Here are 5 Body-Weight Exercises You're Doing Wrong.)

The Mistake: Your hands are too far apart.

Placing your hands wide is a sneaky way to do less work. The reason: It shortens the distance from your body to the floor, says Nepodal. It also puts a greater emphasis on your chest, increasing the stress to your shoulders.

The Fix: Place your palms directly beneath your shoulders. This enables you to keep your elbows tucked close to your sides, working both your chest and triceps, says Nepodal. It makes the pushup harder, but it'll make you stronger in the long run and save your shoulders, he says. (You can Bolster Your Shoulders, put your strength to the test--and grow bigger--with the ultimate overhead exercise.)

The Mistake: You don't shake it out.

Muscle tightness occurs when you create high amounts of tension with load or volume. And while tension leads to strength and size gains, it can also lead to imbalances and pain if you don't release it after the exercise. "You've seen the guy who does a ton of bench presses, and then walks around with his shoulders pulled forward," says Nepodal. "The same thing can happen when you concentrate on both the lowering and lifting of a pushup because you're keeping your pecs and arms under tension longer."

The Fix: Perform a bridge stretch on a Swiss ball between sets. It'll stretch out your core, chest, shoulders, and even your lats, he says. Here's how to do it: Place your head and upper back on the ball, and reach your arms out perpendicular to your body. Let your hips sink toward the floor. Hold this position for 10 breaths. (Try these 5 Secrets to a Perfect Workout and you'll never be held back in the gym again!)

The Mistake: Your neck wobbles.
Nepodal calls this the chicken neck. "It happens when your chest and arms are tired, and your neck juts out toward the floor." Not only does it look silly, but it throws your spine out of alignment and increases your chance of injury. A complete pushup is when your chest, not your nose, touches the floor, he says.

The Fix: Your body should form a straight line from your head to your ankles. If a broomstick were placed on your back, it should make contact with your head, upper back, and butt. Keep your body in that alignment the entire time. (Discover the best muscle advice in Men's Health history!)