Women in their forties are still often told to stick with light weights and high reps. Research suggests many of them would benefit from lifting heavier.
Muscle mass declines by roughly 3 to 8 percent per decade after age 30, according to a widely cited review in Current Opinion in Clinical Nutrition and Metabolic Care. That rate climbs further after 60, and for women, strength losses speed up around menopause, largely for hormonal reasons.
Estrogen Helps Protect Muscle and Bone
A 2019 review in the journal Bone concluded that estrogen deficiency reduces strength in two ways, by making it harder to preserve muscle mass and by lowering the quality of the muscle that remains. It also noted that strength losses accelerate around the menopausal years.
Estrogen supports the satellite cells muscles rely on for repair, according to a 2022 review in Sports Medicine, and exercise can augment or mimic some of that effect. The ERMA study followed 234 women aged 47 to 55 through the transition and found significant losses in lean mass and thigh muscle. Higher physical activity was associated with better-preserved muscle.
Bone density changes over the same years. The Bone Health and Osteoporosis Foundation says a woman can lose up to 20 percent of her bone density in the five to seven years after menopause. The Menopause Society describes an average loss of about 2 percent a year, beginning one to three years before menopause.
Heavy Lifting Built Bone in the LIFTMOR Trial
Some of the strongest evidence that heavy lifting is safe and effective comes from LIFTMOR, published in the Journal of Bone and Mineral Research. Researchers assigned 101 postmenopausal women with low bone mass, average age 65, to either a supervised program of five sets of five reps above 85 percent of their one-rep max, twice a week for eight months, or a low-intensity home program.
Spine bone density rose 2.9 percent in the heavy group and fell 1.2 percent in the light group. At the femoral neck, the heavy group gained 0.3 percent while the light group lost 1.9 percent. Compliance was 92 percent, and the only adverse event reported was a minor lower back spasm.
A 2020 meta-analysis in Calcified Tissue International, covering 84 exercise groups of postmenopausal women, found all types of exercise improved bone density at the hip and spine, with resistance training showing the largest effect at the total hip.
Guidelines Recommend Strength Training at Least Twice a Week
Federal physical activity guidelines call for muscle-strengthening work covering all major muscle groups at least two days a week. The American College of Sports Medicine’s 2026 update suggests loads around 80 percent of one-rep max for two to three sets when the goal is strength.
For women getting started, a sensible approach is to train at least twice a week with compound lifts. Build up gradually with coaching on form, since LIFTMOR participants only lifted heavy under supervision. Anyone with a vertebral fracture should avoid lifts that load the spine in forward bending or twisting, per The Menopause Society, and should get individual advice first.
Diet plays a part as well. The PROT-AGE expert group recommends at least 1.2 grams per kilogram of body weight a day for active older adults, with at least 20 grams after exercise. Creatine has some support for muscle gains alongside resistance training in postmenopausal women, but a two-year trial found no effect on bone density, so it is not a bone treatment.
Muscle Is a Long-Term Health Asset
Dr. Sarah Daccarett, a physician who founded the women’s telehealth practice Inner Balance, believes strength doesn’t get enough attention in conversations about midlife women’s health. She’s more concerned about the muscle and bone women lose without noticing than about their weight.
“Frailty, not the number on the scale, is the real threat as women age,” she says.
For women with symptoms in this stage, the training plan and the hormone conversation are separate but connected. At Inner Balance, that conversation starts with a health assessment reviewed by a licensed clinician.
Starting with light weights is fine. The research suggests building up from there, with good coaching.
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Dr. Sarah Daccarett is a physician specializing in hormone health and the founder of Inner Balance, a clinician-led telehealth practice for women in perimenopause and menopause.
This article is for informational purposes only and does not substitute for professional medical advice. Anyone with osteoporosis, a previous fracture or a health condition should get individual advice before starting heavy training.
