If you still believe that stretching your hamstrings and quads before a jog will help improve your performance, you’ve fallen for one of many popular exercise myths.
Confusing, conflicting and even ridiculous information about exercise gets repeated so often that many of us start accepting it as truth.
“People are always looking for a quick fix or that edge to maximize exercise time and results. However, some of these things are not grounded in exercise science,” said Kristin Ugrob, fitness program director at the Magdalena Ecke Family YMCA in Encinitas.
Fitness misinformation can sabotage efforts to get in shape by leading us to waste time, effort and money on workouts that don’t really work. They can even harm our health and increase our risk for injury.
“Following (fitness myths) doesn’t allow you to maximize your workout and see results, so you’re not as likely to stick with it,” said Jessica Matthews, exercise physiologist with the San Diego-based American Council on Exercise.
Some common exercise myths:
Myth: Exercise allows you to eat anything and as much as you want.
Truth: “It’s calories in versus calories out. You can eat everything you want, you just can’t eat too much of it,” Ugrob said. “It’s important to make healthy food choices and not make up for the calories you’re burning (in exercise) at the table.”
Research has shown that one reason exercisers don’t always see a desired weight is because they misjudge both the number of calories burned during exercise and the number of calories in food eaten.
“Instead of sabotaging your workout efforts, reward yourself with healthful nutrition that supports your health and fitness goals,” Matthews said.
Myth: You can sit for long periods with no ill effects as long as you exercise.
Truth: “New research shows that even if people are physically fit, long, uninterrupted periods of sedentary behavior may be bad for their heath,” Matthews said.
Australian researchers at the Heart and Diabetes Institute at the University of Queensland determined that longer-than-average bouts of sitting and lying down are associated with a higher percentage of body fat in women.
“The take-home message is to try to be as active as possible whenever you can,” she said. “In addition to your regularly scheduled workouts, take the stairs instead of the elevator, park far away from the entrance to the grocery store and take a 10-minute stretching break at work.”
Myth: Strength training gives women bulky, masculine-looking bodies.
Truth: Genetic factors are largely responsible for an individual’s muscular responses to resistance training. This is especially true for women, who typically are smaller in size, have less muscle tissue and produce lower levels of testosterone than men.
“Only a very small percentage of women possess the genetic potential to truly ‘bulk-up.’ Even most men are unable to add large amounts of muscle mass, despite their physiological advantages,” Matthews said.
One appealing aspect of strength training is that it positively affects metabolic rate, allowing the body to burn fat at a slightly higher rate throughout the entire day.
According to Ugrob, each pound of muscle on your body burns about 60 calories a day. So, if you have two pounds of muscle, it’s the equivalent of burning off two chocolate chip cookies, by doing nothing but maintaining that muscle.
Myth: When you stop exercising, your muscle turns to fat.
Truth: Muscles and fat are separate and distinct types of tissue.
“When you stop exercising, the muscle atrophies and you lose that calorie-burning tissue in the body so you build up more fat in that space,” Ugrob said.
Myth: Running is bad for your knees.
Truth: Although it’s a common belief that running will ruin your knees, a number of research studies have reported the contrary.
A 20-year study conducted at Stanford University found that runners’ knees were no more or less healthy than the knees of non-runners. In fact, research has shown that individuals who walk or run regularly tend to have thicker, healthier knee cartilage than their sedentary counterparts.
However, Matthews explained that proper mechanics and strength training are “crucial to minimize the risk of injury and reduce the likelihood of developing knee-related issues such as osteoarthritis.”
A pre-existing knee problem sometimes can be exacerbated by running. In that case, Ugrob recommends cross-training and adding cycling, swimming and walking to a running routine.
Myth: Exercising in the morning burns more calories than exercising in the afternoon or evening.
Truth: “Exercising consistently burns more calories than exercising inconsistently,” Ugrob said. It doesn’t matter what time of day or night you exercise, he added, as long as you do it regularly.
Myth: Static stretching before an event improves performance and decreases injury rates.
Truth: Stretching before an event can actually increase the risk of strains and pulls because the muscles are not sufficiently warmed up, Ugrob said.
Research has shown that pre-exercise static stretching does not prevent injury, nor does it provide any additional protection from muscle soreness. It may also reduce the level of physical performance during activity, according to Matthews.
Static stretching should be part of the cool-down segment at the end of a workout since it’s safer and more effective to stretch muscles that are properly warmed and more pliable. At the beginning of an activity, fitness experts recommend an active, dynamic warm-up involving range-of-motion movements that resemble sport- or movement-specific actions.
“This type of stretching before a workout helps to increase body temperature, enhance joint flexibility and increase muscle elasticity through a range of motion, functionally preparing the body for the activity to come,” Matthews said.
Myth: It’s possible to spot reduce by exercising specific body parts.
Truth: The concept of spot reducing is based on the flawed notion that it is possible to “burn off” fat from a specific part of the body by selectively exercising that area.
“One reason spot reducing sometimes appears to work is if the caloric expenditure is sufficient enough, it will cause fat from the entire body to be reduced, including a particular target area,” Matthews said.
Myth: You burn more calories and fat if you exercise longer at a low intensity.
Truth: You actually burn more calories if you exercise at a higher intensity for a shorter period of time.
One of the best ways to add intensity to a workout is interval training in which short bursts of intense exercise are added to the usual regimen.
“The bottom line is consistent, progressively challenging aerobic exercise will ultimately help your body become a much more efficient ‘fat burner,’ ” Matthews said.