Jennifer Aniston has turned to strength training as the anti-aging protocol more women over 40 trust. Here’s what the science actually supports.
Jennifer Aniston has spent three decades fielding the same question about how she stays the way she is, and at 56 she has stopped crediting genetics. “As we get older, we lose our muscle mass. And that is so important because our bones depend on our muscles to keep strong and keep our skeleton strong so we don’t get frail and brittle bones and fall down and break our hips or suffer osteoporosis and all those awful things that we heard our grandparents talk about,” Aniston, partner of the low-impact fitness company Pvolve, told The Zoe Report last October. “That no pain, no gain [mentality] I think goes right out the window,” she said.
More and more women are making the same shift, treating built muscle as the thing that keeps skin, bones, and mobility intact with age. Money that used to go entirely to serums and lasers is increasingly going to dumbbells, protein, and a trainer.
Strength training’s rise in women over 40
Muscle is living, working tissue, and everyone loses it with age. Skeletal muscle mass drops by roughly 3 to 8 percent each decade after 30, and faster after 60, according to a review in the International Journal of Environmental Research and Public Health. For women, that loss lands at the same time as menopause, when falling estrogen thins bone as quickly as it thins collagen.
Dr. Vonda Wright, an orthopedic surgeon who writes about female longevity, argues that the usual anti-aging pitch insults the women it targets. “For generations, when you think of women living longer, the solution is anti-aging, as if there’s something wrong with us. There’s nothing wrong with us. We are aging in a different way than men,” she told CNN last September. What she is after is not a smaller number on the scale but a different body composition. “We are not losing weight. We are recomposing, meaning it matters what we’re made of, because we’re trying to maximize lean muscle and minimize body fat — not to be skinny but to be lean,” she said. Women can lose 15 percent to 20 percent of their bone density during the perimenopause years, Wright told the network, and muscle pulling on bone is one of the few things shown to slow that loss.
The benefits of building muscle
Dr. Gabrielle Lyon, the physician who coined the term “muscle-centric medicine,” treats muscle as central to metabolic health, not just appearance. “The more healthy muscle mass you have, the greater place for glucose disposal,” she said on the mindbodygreen podcast. She is sharply critical of how the current weight-loss boom ignores it. As GLP-1 drugs like Ozempic strip fat and often muscle along with it, Lyon warns the country is “trading one epidemic for another.”
Those drugs are part of why lifting has caught on. People who take them tend to lose muscle as well as fat, which is why doctors now pair the medication with strength training and more protein. Losing weight without protecting muscle, Lyon and Wright both argue, leaves a woman weaker in the years she can least afford it.
The payoff women describe is not only physical. “If you learn to lift heavy, what happens physically is you get stronger. But every time you’re done lifting, your brain feels invincible,” Wright told CNN. That sense of capability, more than a dress size, is what tends to keep women coming back to the weights.
Protein and recovery
For years, women were told to do cardio and eat less. The advice now runs the other way, toward lifting heavy and eating far more protein. Wright recommends “1 gram of protein per ideal pound a day, so that we support the muscle we’re trying to build,” a target most women fall well short of. Lyon points to leucine, the amino acid that triggers muscle growth, advising “around 2.5 grams of leucine per meal.” Harvard Health says the range is 1 to 1.3 grams of protein per kilogram of body weight for older adults who do resistance training, well above what most people eat.
Getting women to actually lift is the harder part. Barely one in five does. In 2020, 20.4 percent of women met federal guidelines for both aerobic and muscle-strengthening activity, compared with 28.3 percent of men, according to the Centers for Disease Control and Prevention, and the share drops with each decade, to 17.6 percent among women 50 to 64 and 10.8 percent past 65. The women with the most to gain from lifting are the least likely to do it.
Lifting weights will not smooth a wrinkle or erase a sunspot, and calling muscle “the ultimate anti-aging tool” oversells what it does for the surface of the skin. What it does do matters more. Strength held into old age is what keeps women mobile, out of the hospital after a fall, and living on their own, a bigger promise than a firmer face and, unlike most anti-aging claims, one backed by evidence.
Aniston frames it around the decades ahead rather than the face in the mirror. “I just keep doing what I’m doing and I keep myself strong,” she said. “I keep myself healthy.”
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