If you’ve ever observed a skinny teenager scarfing down a big tray of fast food, and thought to yourself, “I used to be able to eat like that,” you’re definitely not alone. There comes a point when indulging in a daily burger and fries cannot be done without consequence. The reason: As we age, our metabolism, or our basal metabolic rate (BMR), begins to decrease. And whether we like it or not, it’s a normal part of the aging process.
Simply put, BMR is the amount of energy (or calories) needed to keep your body functioning at rest. Three primary things influence BMR: your age, your weight, and your muscle mass. The lighter you are and the less muscle you have, the fewer calories your body needs to function and the slower your metabolism becomes.
Unfortunately, with each passing decade, muscle mass declines by five to 10 percent. As a result, your BMR begins to slowly decrease one to two percent every 10 years. (That means if you used to consume 1,500 calories to maintain your weight, you’d need to cut 15 to 30 calories from your daily diet to ward off weight gain.) This process starts at the not-so-ripe age of 20—and further decelerates after men turn 40 and after women turn 50.
That said, it’s no surprise that Johns Hopkins University researchers discovered that from early adulthood to middle age the average person gains one to two pounds per year. While it’s not possible to stop the aging process (sorry!), it is possible to control how much muscle mass we have—and that’s where hitting the gym comes into play.
Participating in a few weekly strength training sessions can help build muscle, and in turn, boost your metabolism so you can slip into those skinny jeans at any age—without counting calories. How’s it work? “Muscle is extremely metabolically active, meaning that it burns calories even when you’re at rest,” explained board-certified internist and endocrinologist Brunilda Nazario to U.S.News. Body fat, however, cannot make the same claim.
And before you claim to be “too old” to add muscle to your frame, know this: Studies show that healthy middle-aged and elderly adults can build muscle and rev their metabolisms—just like their younger counterparts. If that doesn’t inspire you to grab some dumbbells or hit a weight lifting class at your local gym, we’re not sure what will!
For optimal results, remember to follow up your workouts with a source of protein and a healthy carb (like an apple or an orange) to replenish your lost glycogen stores and rebuild your muscles.