While it may sound counterintuitive, a growing number of women are opting to carry even more weight on their shoulders.

In pursuit of preserving strength, a slew of middle-aged women are purchasing weighted vests to optimize their health and counter age-related muscle and bone loss.

Katie Couric, former longtime Today anchor and cofounder of Katie Couric Media, began sporting a weighted vest this summer to strengthen her muscles and bones. Her Pilates instructor assured her that she wouldn’t be the only one donning a vest on her walk, in a video the two posted to Couric’s followers.

View this post on Instagram

A post shared by Katie Couric (@katiecouric)

Dr. Mary Claire Haver—known as social media’s leading menopause doctor under the account “The Pause Life”—has been one of the most viral to show off the weighted vest to her over 2 million Instagram and TikTok followers. Style aside, she swears by it for the same reasons as Couric: its ability to improve strength.

“I’m just trying to stay strong as long as I can,” Haver tells Fortune, who, as a practicing OBGYN and author of the NYT best-seller The New Menopause, often recommends the vest to her patients. “This is a gift to your future self to help keep your bones and muscles strong and even make them stronger, so that you’re more resilient to the effects of aging.”

Haver wears one of her six weighted vests when she is on Zoom calls, walking on the treadmill, and while cleaning around the house. She clocks in around an hour a day with the vest on, she tells Fortune.

Vest costs vary widely, from about $25 online for basic models to over $250 for athlete-endorsed G Vests from the brand OMORPHO, whose share of women who use the vests at least once a week have increased by 15% since 2022, according to the company’s sales team and survey data.

More women are regularly wearing weighted vests, according to sales and survey reports from OMORPHO.

Haver has been one of the voices leading the charge in destigmatizing aging for women. She’s joined by a growing number of celebrities, business leaders, and health experts who want to scream about menopause from the rooftops, educate viewers, and offer helpful ways to combat the realities of this normal part of life for middle-aged women.

What are the health benefits of a weighted vest?

As women approach their forties, they begin to naturally lose muscle mass, a process referred to as sarcopenia. Menopause accelerates this muscle and bone density loss as the hormone estrogen, which plays a crucial role in bone health, declines.

Wearing a weighted vest while walking or even doing house chores adds a a layer of resistance to your body that causes you to engage your muscles in ways you otherwise wouldn’t—similar to how walking with a bag of groceries activates your arm muscles.

“The muscle is something that the aging process chips away at, but it’s not inevitable,” Haver says, adding that to combat the phenomenon, “you have to work at it.”

However, many women have been undereducated on the realities of aging and menopause.

“I grew up in a generation of women where my only job was to be thin, and [I was told that] thin was healthy. All I did was aerobics. I didn’t lift weights. I didn’t do anything to try to keep my bones and muscles healthy,” Haver says.

View this post on Instagram

A post shared by Mary Claire Haver, MD, author The New Menopause (@drmaryclaire)

But as she saw more women develop osteoporosis, have fractures, and need surgery, she searched for a more novel solution for her patients and herself.

“What are some things that women can do at any age, especially starting younger, that would benefit them and their bone and muscle strength?” she asked herself. Osteoporosis, a disease that weakens bones and can cause fractures and breaks, affects one in five women over 50 compared to one in 20 men, according to the National Institute on Aging.

Haver came across a study from 2000 that found postmenopausal women who wore a weighted vest during a workout for five years were significantly less likely to lose bone mineral density in their hips.

56-year-old Joanna Strober, CEO of MIDI Health, a menopause care company, began wearing a weighted vest two years ago following a diagnosis of osteopenia, a loss in bone density that can become osteoporosis. In her latest scan, Strober says she has not lost any more bone density and has, therefore, slowed the progression of the disease. She credits a combination of the vest, weight training, and hormone replacement therapy.

Joanna Strober wears her weighted vest outside with a cup of coffee.

“It’s another way of keeping my bones strong,” Strober, who now wears an 18-pound vest while walking three or four times a week, tells Fortune. At MIDI, Strober’s work is reflective of her own health journey, and her mission is to “help women stay strong,” not merely treat menopause symptoms.

The Centers for Disease Control and Prevention (CDC) recommends weekly strength training, and specifies the importance of resistance training for older adults to counter the effects of muscle loss. If you’re willing to give the G.I. Joe look a try, the weighted vest may be an even more accessible strengthening tool to consider adding to your routine.

What kind of weighted vest do I buy?

Haver recommends her patients wear a weighted vest that is 5% to 10% of their body weight (so, someone who is 150 pounds would start with a 7.5-pound vest). Over time, you can increase weight, she adds.

“Even sitting with a weighted vest is better than sitting without one,” she says. “The body responds to resistance always.”

And Haver, who routinely walks in her neighborhood alongside her closest female friends, is here to normalize the tools she uses to optimize her health as she ages. You can find Haver, and eight of her friends, all leveling up the “hot girl” walk in Galveston, Texas, with their matching weighted vests.

“Everyone’s curious and wants to know about it,” she says.

Of note: Those with shoulder, back, or knee pain should check with their doctor about whether a weighted vest is right for them and how to properly incorporate it into their routine.

For more on aging well:

AARP’s new CEO vows to protect Social Security, Medicare, and ensure older adults age ‘on their own terms’
3 ancient foods are the staple of this blue zone’s longevity diet
4 tips to live a longer and healthier life

Women over 40 swear by a simple hack to build strength and counter aging