Momentum comes in handy when you're attempting a long-jump, but not if you're lifting weights. Each exercise involves two phases: a concentric (contracting) move and an eccentric (stretch) phase. "Building momentum by swinging your arms when doing a move like a bicep curl or a tricep push-down sacrifices results by not controlling the eccentric phase, and also increases your risk of injury," says Irv Rubenstein, PhD, exercise physiologist and founder of STEPS Fitness, a science-based fitness facility in Nashville. Practice a two-second count on the concentric move and a four- to five-second count on the eccentric.
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You Hold On For Dear Life
Grasping the sidebars when walking on the treadmill or hanging on tight to the handles of the elliptical trainer cheats you out of the best possible workout, says Rubenstein. "In addition, if you're using your arms to make it easier on your legs, you'll tire faster, because your arms can't work as hard as your legs," he says. Instead, use the rails only as a guide, keeping your fingertips lightly on them. If you find it impossible to maintain proper form without clutching the bars, try lowering the incline or slowing down your pace.
Holding a stretch for only a few seconds does little to increase your flexibility. The right way to stretch: Hold still (no bouncing!) for at least 20 to 30 seconds. "Another common cheat comes during a hamstring stretch," says Rubenstein. If you round your back so you can reach farther down your extended leg, you're preventing your hamstrings from actually getting stretched. It also puts unnecessary strain on your back.
You Play The Waiting Game
Few things are more frustrating than dealing with a crowded gym, especially when other exercisers occupy the machines and equipment you'd planned on using. But, waiting around wastes valuable time, says Tom Holland, exercise physiologist and author of Beat The Gym. "Don't wait for the equipment to be available — instead, fill time with exercises you can do without a machine, such as crunches, planks, or push-ups," he says. Or, you could jump rope or do a set of high-knees, suggests Jessica Matthews, assistant professor of exercise science at Miramar College in San Diego. Anything's better than waiting around: "Spending five or more minutes between sets negatively impacts the overall quality and effectiveness of your workout," Matthews says.
Seems like a good way to save time, right? Wrong. "Stretching between exercises, especially static stretching, may decrease the amount of weight you can lift," Rubenstein says. So, leave stretches for the end of your workout, as part of your cool-down.
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When The Going Gets Tough, You Stop
Simply showing up isn't enough if you don't put any real effort behind your moves, says Holland. "You can easily cheat your workout, even during an intense cycling class," he says. "If you don't increase the tension when the instructor tells you to, you can coast through and barely break a sweat." The same applies to other classes; maybe you substitute a difficult move (burpees) with an easier one (jogging in place). Instead, when you need a boost, try repeating a positive mantra to yourself, which may help you push through when you'd rather quit. A recent study published in Medicine & Science in Sports & Exercise found that cyclists who recited positive self-talk pedaled two minutes longer than those who did not. Tell yourself, "I am strong" or "I can do this."
Skipping out on the warm-up or cool-down means you're missing a couple of crucial components of the class experience, says Matthews. "The warm-up phase allows for your body temperature and heart rate to gradually increase, which helps reduce the risk of developing injuries, while also preparing you for the main conditioning phase of the class," she says. Meanwhile, abruptly stopping after an intense workout can produce pooling of blood in the lower extremities, which can sometimes lead to dizziness and even fainting, she says. So, show up on time and stick with it to the end.
You're A Bookworm
If you're reading this article while you're on the treadmill, you're not working hard enough, says Holland. "If you can read, text, or otherwise give your attention to some other non-workout related issue, you're cheating yourself." Put down the magazine and smartphone and focus on the task at hand. An exception: music. Listening to tunes while working out can reduce your perception of effort and increase endurance by 15%, according to several studies. So, switch your book for an iPod for a more enjoyable, longer workout.
Most gyms have televisions so members can catch up on the news or watch movies while doing cardio, and some even feature them in weightlifting areas. But, spending half your workout flipping through the channels distracts you from the reason you came to the gym in the first place, says Holland. Pick a channel and leave it there so you can spend the rest of your workout focusing on your fitness.
You Only Do One Type Of Workout
Don't stick to just one routine. Studies have shown that constantly mixing things up — for example, going for a run one day, while strength-training the next, and practicing yoga later in the week — is a smarter choice for optimal health. To prevent plateaus, you want to constantly keep your body and muscles guessing.
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