Muscle Loss in Men After 50

Men start with more muscle than women, which can make its loss easy to overlook until stairs feel steeper or a jar lid won’t budge. If you’re looking into muscle loss in men after 50, a few things are specific to men: where the loss happens, how testosterone fits in and how prostate cancer treatment can speed it up. Humanic Blue follows those threads separately rather than treating one hormone as the whole story.

Muscle loss does not begin on every man’s 50th birthday. A whole-body MRI study compared people of different ages and found lower muscle mass after midlife, largely in the legs. It could not establish when any individual began losing muscle. Prostate-cancer hormone treatment can also reduce lean tissue. Exercise trials in men receiving or previously treated with that therapy found improvements in strength and some everyday movement tests. The American College of Physicians advises against starting testosterone solely to improve physical function in men with age-related low testosterone. For living longer and better, strength and function matter—but these studies did not test whether preserving muscle extends life.

Where do men tend to lose muscle with age?

In the 2000 study from Queen’s University in Canada, researchers used whole-body MRI scans in men and women ages 18 to 88. Men had more skeletal muscle than women on average: 33.0 kg versus 21.0 kg. Muscle as a share of total body weight was lower in older age groups from earlier adulthood. The more marked difference in the total weight of muscle appeared after midlife and was largely explained by lower-body muscle. Because the design compared different people at one point in time, it describes an age pattern rather than proving when any participant began losing muscle.

That lower-body pattern matters because leg strength drives walking, stair climbing and getting up from a chair. The timeline and accelerators in your 50s, including inactive stretches and bed rest, are covered in Prevent Muscle Loss After 50.

How it’s measured. Sarcopenia is a muscle disorder involving low strength and low muscle quantity or quality. The European Working Group on Sarcopenia in Older People uses grip strength below 27 kg in men as one signal of probable sarcopenia. That is the force reading from a grip-testing device, not body weight. Confirmation requires evidence of low muscle quantity or quality, and poor physical performance indicates greater severity. The cutoff is a clinical case-finding tool—not a diagnosis or individual prognosis—and depends on standardized measurement, as covered in Grip Strength and Longevity.

The testosterone question

Testosterone falls slowly with age, and observational research links weight gain to further declines, as covered in Testosterone and Aging. It’s tempting to see low testosterone as the cause of muscle loss and testosterone therapy as the fix.

The trials do not support testosterone as a general treatment for age-related loss of function. In the Testosterone Trials, men age 65 or older with symptoms and an average of two testosterone readings below 275 ng/dL (nanograms per deciliter of blood) received gel or placebo for one year. The prespecified physical-function trial outcome was not significantly better, although a pooled analysis across trial participants favored testosterone. The American College of Physicians’ 2020 guideline advises against starting testosterone for physical function, energy, vitality or cognition in men with age-related low testosterone. The full trial results, current regulatory status and risks are covered in Testosterone Therapy and Healthy Aging.

What does a change in lean mass leave unanswered about strength and everyday function?

How can prostate cancer treatment change muscle?

Androgen deprivation therapy (ADT) reduces the production or action of hormones such as testosterone to treat prostate cancer. Lean mass, a measure used in these studies, includes muscle and other tissue that is not fat; a change in lean mass is not a pure measurement of muscle. In a 2002 study without an untreated comparison group at Massachusetts General Hospital, men with prostate cancer that had not spread to distant sites began leuprolide, a hormone-suppressing drug. After about a year, the men assessed had sharply lower testosterone, lower lean mass and muscle area beside the spine, and more body fat. Without an untreated control group, the study cannot assign every change solely to the drug, but the direction is consistent with the recognized musculoskeletal effects of ADT.

Exercise can counter some of those changes. In a 2010 Australian trial from Edith Cowan University, men who had already received androgen suppression for more than two months were randomized to 12 weeks of supervised resistance-plus-aerobic training or usual care. The exercise group improved whole-body and regional lean mass, strength and several physical-function measures; no adverse events were reported. The trial was small and short and did not test cancer outcomes or lifespan.

A 2023 individual-participant-data analysis combined trial data from men with prostate cancer who were receiving or had previously received ADT, averaging about 70 years old. Resistance-based programs improved whole-body and limb lean-mass measures, relative muscle strength and selected walking tests on average. Effects varied, and the analysis examined intermediate outcomes rather than fractures, independence, cancer control or survival. The authors declared no competing interests. How prostate cancer is detected and treated is covered in Prostate Health as You Age.

How does the treatment context change the interpretation of muscle-loss evidence?

What has helped counter muscle loss in studies?

Resistance training—working muscles against weights, bands or other resistance—was a common part of these exercise programs. A 2011 synthesis of studies in adults age 50 or older found that participants gained about 1.1 kg of lean body mass on average after roughly 20 weeks. That estimate compared participants with their own starting measurements, rather than consistently comparing exercise with no exercise. Results varied greatly across studies, and an apparent link between more training and greater gains came from comparisons between studies, not trials assigning different exercise amounts. Newer randomized evidence also supports improvements in strength and function with relatively low training volumes, as covered in Prevent Muscle Loss After 50. How to structure training is in Build Muscle After 50.