Lies Overheard at the Gym
Do you still believe a dance class can lengthen your muscles? We take that to task—along with other myths about exercising.
fitness myths
Running causes knee arthritis.
Runners of a certain age are often encouraged to enjoy every mile while they're still healthy because their knees are doomed. And it's true that with every sneaker-clad step, you hit the ground with enormous force—it's estimated to be about eight times your body weight. But all that pounding does not substantially increase the risk of knee arthritis in healthy people, several studies have concluded—including one of almost 75,000 runners. While runners hit the ground harder, they also take longer strides and fewer steps, and therefore hit the ground less often. So, over time, running produces no more wear and tear on the knees than walking. (Note: Runners' knees could still be susceptible to injuries unrelated to arthritis, like patellofemoral pain syndrome, which can happen at any age.)
fitness myths
Certain exercises can elongate your muscles, creating a longer, leaner, more dancer-like physique.
The proponents of this myth (hint: They're usually wearing a leotard) swear that stretching, reaching, contracting and pulsing moves can help you develop longer, leaner muscles (as opposed to those infamous "bulky" muscles you often hear about—which probably wouldn't ever happen because your testosterone level is naturally too low). In Pilates and ballet-style workouts, you isolate different muscles and tighten them, then slowly control the release (or you contract, contract more, contract more, hold...then release). Instead of putting a heavy load on the muscle (in the form of a dumbbell, for example), you work against gravity and your body's own resistance. These moves cannot permanently lengthen the muscle, says Jessica Matthews, an associate professor of exercise science at Miramar College in San Diego. Nothing can, because muscles are attached to the bone at specific points, so the only way to lengthen them is to surgically detach and reattach them. However, Pilates and other dance-inspired exercises can improve your flexibility, increase joint mobility and significantly strengthen all of the muscles that make up your core, Matthews says. When your core is stronger, you stand straighter, and you'll probably look taller—even if your muscles have not grown in length.
fitness myths
Muscle weighs more than fat—so despite what the scale says, you're still losing weight.
You've amped up your workouts to include weightlifting, but you notice the numbers on the scale slowly creeping up instead of down. Must be because of all that heavy muscle you're putting on, right? Matthews explains that you should be still be losing fat, and it's unlikely that it will be "replaced" by weight in the form of muscle. So if you are gaining weight, it's more likely due to the extra calories you may be consuming (consciously or unconsciously) to recover from your workouts. Beware of calorie-packed protein drinks and bars marketed for gym-goers, and refuel with healthy snacks like low-fat chocolate milk or nuts.
fitness myths
You can do mouth exercises to get rid of chin jiggle.
One more time: You can't precision-target fat loss. It's just not possible to burn off the jiggle under your chin—or your arms or the backs of your legs or any other specific 5-inch-by-5-inch-square area. When you lose weight, you lose it all over your body, explains Matthew Berenc, director of the Equinox Fitness Training Institute. Some people may happen to notice more of a difference in the way that exercise makes their jaw or arms look, but it's in their genes—there's really nothing the rest of us can do to guarantee those results.
fitness myths
You shouldn’t drink water during yoga class.
Your yoga instructor may argue that reaching for your water bottle in the middle of class breaks your concentration—but so does the woozy, lightheaded feeling that can result from dehydration. As for the claim that sipping water between asanas affects your subtle energies and cools your system in a way that negatively affects your physical practice: This has yet to be proven by science. A few sips—not guzzles—during your practice won't make it more difficult to perform poses, says Matthews (who, as a registered yoga instructor, teaches classes with the yoga certification program at Miracosta College) and can be especially important during Bikram or other challenging classes in which you're sweating profusely. Your instructor may want you to learn how to manage mild discomfort, but that doesn't mean she wants you to suffer (and if it does, you might want to find another yogi).

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