Five Cardio Myths You Need to Stop Believing

Five Cardio Myths You Need to Stop Believing  from Women’s Health

At the end of a rough day, the rhythmic swooshing of the elliptical, whir of a bike, or patter of feet on the belt of a treadmill might sound like music to your ears—for stress relief, cardio is effective. It's also, of course, good for your heart (um, it's in the name), and helps burn calories (BUT you already know not to trust the calorie counter on the display, right?). Still, while all that good stuff is true, there are a lot of fallacies running around out there, and following them may be stopping you in your fitness tracks. Here, 5 of the biggest cardio myths:

MYTH #1: Cardio, cardio, and more cardio is the ticket to faster weight loss.

FACT: Hours logged on those fast-paced gym machines alone are not the best way to melt off the FAT. "You may lose “weight” doing cardio only, but unfortunately it's the wrong kind of weight," says Kansas City-based personal trainer Greg Justice. Cardio alone burns away both muscle and fat. 

For a lasting change, you have to integrate strength workouts into your routine. "Weight training builds lean muscle mass, which elevates your metabolism and burns more fat, even when you're not exercising," says Justice. He recommends Metabolic Resistance Training, a hybrid method in which weight training is done at a faster pace, with minimal rest. One example of this double whammy: kettlebell training.

MYTH #2: If you don't have an hour to commit to the cardio gods, it's not worth it.

FACT: Flat-out not true. All body movement contributes to calorie burn. What you can change, though, is how efficiently you burn those calories. "You may be able to do lower intensity, steady-state cardio longer, but the key is what happens after your workout," says Justice. "By doing high-intensity interval training [HIIT], which means you incorporate intense periods of work with short recovery, your metabolism is elevated and you'll be burning calories for up to 38 hours after your HIIT workout is completed." So, if you think you have to pray at the altar of the treadmill, take heart. "The American Heart Association says that doing three, 20-minute sessions of cardio at a vigorous intensity is the equivalent of doing five, 30-minute sessions at a moderate level [like fast walking]," says exercise scientist Wayne Westcott, Ph.D. Even 10 minutes at a high intensity is beneficial. And a recent study suggests that short, infrequent bouts of slow running can do your heart good. So, no excuses that you don't have the time!

MYTH #3: Doing cardio on an empty stomach torches maximum body fat.

FACT: This one comes from the idea that if your body doesn't have readily available food calories, it'll dip into the body's stored fat supply, shrinking that muffin top. Research bears out that the opposite is true: A 2011 meta-analysis concluded fat burn is consistent regardless of whether or not you've eaten before a workout. And other research shows an unfavorable effect on muscle catabolism (a.k.a. muscle loss) from skipping a pre-workout snack. "Your body needs energy to perform and energy comes in the form of food,” says Justice. "I'm not talking about gorging yourself, but having a small (healthy, balanced) snack before doing cardio can actually help you perform at a higher level."

MYTH #4: It's important to stay in the "fat-burning zone" if your aim is to burn fat.

FACT: Like a lot of fitness fallacies, this one seems logical, but the details reveal a different picture. At a lower intensity—the heart rate deemed the "fat-burning zone"—you will indeed burn a greater percentage of your calories from fat. But, as Westcott explains, its total calories burned (those pesky calories out) that matter for fat loss, not the percentage. The math: If you run at 7 miles per hour, you’ll burn 25% of your calories from fat, while walking at half that speed at 3.5 mph burns 40% from fat, says Westcott, citing past research. So far, walking seems to have an edge. However, at that 7 mph pace, you might burn about 500 calories in 30 minutes, which would amount to 125 fat calories. At the 3.5 mph walking pace, you might burn about 250 calories in the same time, and 40% of 250 is only 100, so neither total calories nor the "fat-burning zone" doesn't win that race. Bottom line: Working out at a higher intensity equals more total calories torched, which is what leads to more pounds lost.

MYTH #5: If you go for a run or a bike ride, you can skip a leg strength workout. FACT: Unless you're doing full-on sprints uphill or cranking the bike's resistance to the point where you can barely push the pedals (and yet you push), you are not getting much muscle-building benefit from your workout.

So while you feel like your legs and glutes did some work, in order to get the awesome metabolic gains of strengthening and sculpting those largest muscles in your body, you have to incorporate strength moves like squats, deadlifts, and lunges. Not only that, but strength workouts will make you a better runner and cyclist. "Back when I coached track at Penn State, our runners dominated the sport," says Westcott. "We were the only ones at the time having our athletes strength-train. Now, of course, everybody does.”