Fitness Myth No. 2: Doing crunches or working on an "ab machine" will get rid of belly fat.
Don't believe everything you hear on those late-night infomercials! Harr says that while an ab-crunching device might "help strengthen the muscles around your midsection and improve your posture," being able to "see" your abdominal muscles has to do with your overall percentage of body fat. If you don't lose the belly fat, he says, you won't see the ab muscles.
But can doing ab crunches help you to lose that belly fat? Experts say no.
"You can’t pick and choose areas where you’d like to burn fat," says Phil Tyne, director of the fitness center at the Baylor Tom Landry Health & Wellness Center in Dallas. So crunches aren't going to target weight loss in that area.
"In order to burn fat, you should create a workout that includes both cardiovascular and strength-training elements. This will decrease your overall body fat content," including the area around your midsection, he says.
Fitness Myth No. 3: An aerobic workout will boost your metabolism for hours after you stop working out.
This statement is actually true -- but the calorie burn is probably not nearly as much as you think!
Harr says that while your metabolism will continue to burn at a slightly higher rate after you finish an aerobic workout, the amount is not statistically significant. In fact, it allows you to burn only about 20 extra calories for the day. While there's a little bit more of a metabolic boost after strength training, he says, it's still marginal.
"It doesn't really count towards your caloric burn," he says.