6 Surprising ways you’re sabotaging your workout

You huff and puff your way through weekly cardio workouts, and after all that sweating you want to see results, not that same stubborn layer of flab around your middle, right? The irony is that if your pudge won't budge, your workout might be to blame. Here's what top trainers and exercise physiologists wish you would stop doing-and how to tweak your routine quickly so you can reap the rewards of all your hard work.

1. You Sacrifice Good Form

High-intensity exercise may burn loads of calories, but not if you're hanging onto the handrails for dear life. It's important to focus on your form, even if that means lowering the intensity; otherwise, you won't recruit as many muscle fibers, so you burn fewer calories. Same goes for strength-training, according to James Levine, PhD, a scientist at the Mayo Clinic in Rochester, MN; his research has found that standing while lifting weights boosts calorie burn by about 50 calories per half-hour. Best of all, one study shows that good posture allows you to take in more oxygen so your workout feels easier, even while you're blasting more calories.

Do instead: Slow down and stand tall: You can burn 50 extra calories per session.

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2. You Exercise While Parched

Experts are constantly back and forth on the merits of the 8-glasses-a-day guideline. However, when it comes to working out, the importance of drinking up is clear. Nearly every cell in the body is composed of water-without it, they don't function efficiently during exercise, according to Dan Judelson, PhD, an assistant professor of kinesiology at California State University in Fullerton. Translation: You'll fatigue faster and your workout will feel tougher than it should.

Do instead: Sip 15 ounces of water 2 hours before working out.

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3. You Read on the Treadmill

If flipping through a magazine keeps you motivated, by all means do it, but the reality is that reading while exercising is so distracting that you're probably working at an intensity too low to burn a significant number of calories.

Do instead: Listen to upbeat music (save the mellow stuff for your next dinner party). According to researchers at Brunel University in London, this can increase the duration and intensity of your cardio bout; according to their research, runners who listened to motivational rock or pop music (think U2 or Madonna) exercised up to 15% longer--and felt better doing it.

Rock out to your favorite music during these treadmill workouts.

4. You Hate Your Workout

Seems obvious, but no matter how many calories an activity promises to burn, if you don't enjoy it, you'll be less likely to do it and won't reap the benefits. Think of it this way: If you burn 300 calories every time you exercise, but you dread it so much that you skip one session a week, it adds up to 1,200 calories a month-or more than 4 pounds a year.

Do instead: Any workout you want to do, rather than one you feel like you have to do. When University of Nebraska-Omaha researchers polled women who'd been exercising regularly for longer than a year, they found that one of the top predictors of adherence was choosing enjoyable activities.

Learn how to fit fitness into your day with surprisingly short bouts of activity.

5. You Skip Strength-Training

Over 80% of women forgo lifting weights, says the latest survey by the Sporting Goods Manufacturers Association. If you're one of them, it may be the number one reason that your scale is stuck. You've probably heard that strength-training can boost metabolism, but here's something you may not know: People who pair aerobic and resistance training eat less-517 fewer calories a day-than those who do only cardio, reports a new study in the Journal of Sports Science and Medicine. The combo workouts may increase satiety hormones more and boost the body's ability to break down food and stabilize blood sugar, so you feel full longer, says study author Brandon S. Shaw, PhD.

Do instead: Swap aerobic exercise for weights 3 times a week and you could lose 12.5 pounds in a year from this switch alone.

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6. You Believe Calorie-Burn Estimates

Oh, how sweet it would be if 20 minutes on a cardio machine really did blast 400 calories. But like most things in life that sound too good to be true, those digital displays broadcasting mega calorie burn are often bogus. Recent research presented at the National Strength and Conditioning Conference found that elliptical trainers over-estimate calorie burn by an average of 30%. If you're trying to create a calorie deficit to lose weight, those thought-you-burned-'em calories can add up over time and thwart your success.

Do instead: Consider investing in a heart rate monitor; the FT40 by Polar is a cinch to set up and use ($180; polarusa.com). Input some basic info (weight, height, age, activity level, and so on) and the gadget will accurately track your heart rate to compute the number of calories you torched.

Find out how eating can actually help you lose your pooch.

More Easy Tips for a Healthy and Trim Body from Prevention:

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20 Satisfying Meals That Help You Lose

Hour-by-Hour Eating Tips

Excuse-Proof Healthy Eating Plan

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