Strength training is better at much building muscle than a cardio-only routine, explains Michaela Devries-Aboud, Ph.D., an exercise physiologist at McMaster University. “When you lift weights, you overload the muscle and it works to adapt to be able to lift more weight. The way the muscle adapts is by increasing something called myofibrillar size (the contractile units of the muscle),” she explains. Resistance training stimulates this growth, which leads to an increase in muscle mass over time. “And while aerobic exercise can also [stimulate this process], this increase is not as great as it is with resistance exercise.”
More muscle = a higher BMR (base metabolic rate).
Having more lean muscle means your body will burn more calories at rest. Having more muscle increases your everyday base metabolic rate, or BMR (AKA, how many calories your body would burn just to keep itself running if you did nothing but binge on Netflix all day). “Muscle mass is a more metabolically expensive tissue,” explains Devries-Aboud. “The metabolic demand of a pound of muscle is greater than it is for a pound of fat, so just sitting around, the amount of energy needed to maintain a pound of muscle per day is greater than that of a pound of fat. The more muscle you have the more calories you burn throughout the day.”
“Muscle is constantly being broken down, recreated, and synthesized, and all these processes require energy. The more muscle you have, the more energy it takes for this process,” adds Tamir. So by building more muscle, you’re stoking the fires of your metabolism. By increasing your BMR and burning more calories at rest, you’re also increasing your calorie deficit, which is necessary for weight loss. (Head over here to get all of the formulas and information you need to figure out how many calories you should eat for weight loss.)
And don’t freak out if you don’t see huge results on the scale: “Go by how your clothes fit, because muscle is more compact than fat,” suggests Devries-Aboud. If you’re not losing as much weight as you think you should be, you’re probably building muscle as you’re losing fat, and that’s a good thing! (And no, you won’t get bulky.)
“That new muscle has a huge influence on decreasing body fat,” explains Holly Perkins, B.S., C.S.C.S. “The net result is that you are tighter and leaner, regardless of what the scale says.”
You’ll still burn calories during a strength workout.
Even though cardio gets a lot of the credit when it comes to calorie-torching workouts, you can still get a great burn during a strength-training session by adding in some heart-pumping elements. There are several things you can do maximize your burn, says Perkins: Move faster between exercises, don’t rest between sets, move quickly during each set, increase your reps, and choose heavier weights (but don’t go so heavy that you risk injury, of course). Or, “add a five-minute cardio burst in-between strength moves: Hop on the treadmill and jog or sprint for five minutes,” says Perkins.
“These methods work mostly because they increase your heart rate during the workout,” she explains. “An increase in heart rate means a greater need for fuel, and a greater need for fuel means that your body will demand more calories. Also, as a result of an intense workout, your excess post-exercise oxygen consumption, or EPOC, will [go up and] result in more calories being burned after the workout. Think of EPOC as a temporary boost to your metabolism.” This is known as the afterburn effect.
Here’s how to add strength training into your weight-loss plan.
At the end of the day, you still have to burn more calories than you take in to lose weight, and even though building muscle can help keep that up long-term, it’s still important to chip away at calories on a day-to-day basis. “Having a challenging cardiovascular routine helps in your caloric deficit,” says Tamir.
Moral of the story: Do both strength training and cardio, says Tamir. It’s important to include both types of training in a successful weight-loss plan. In general, Tamir recommends strength training three to four times a week for 45 to 60 minutes. “Strength training also gives you the ability to endure more during your aerobic training,” notes Tamir. “The stronger you are, the less effort it takes for you to complete aerobic exercise.”
This means you can increase your performance in cardio-based activities: “For example, having strong glutes for running helps you go faster for longer, which burns more calories. And doing exercises to strengthen your core can help you maintain form for biking, which can also help you burn more calories,” says Tamir.
So no need to ditch the dance cardio or treadmill workout—just throw some weights into your routine a few times a week, too.
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