In a long observational cohort, people reporting 90 to 119 minutes of weekly strength training had about 13 percent lower mortality than those reporting none. The association flattened at higher amounts, but the study cannot establish that the exercise caused the difference or that two hours is an optimal dose.
That is the headline finding from one of the longest looks yet at resistance training and how long people live. Researchers tracked 147,374 people, most of them American nurses and health professionals, for up to 30 years, and watched what happened.
The benefits of aerobic exercise, the running and brisk walking and cycling that gets you puffed, have been nailed down for decades. Lifting weights has been murkier. We knew muscle-strengthening work was good for you in a general way, which is why the guidelines have long nudged us towards it at least twice a week, but the precise dose, how much actually buys you the most life, stayed fuzzy. Most earlier studies measured people’s habits just once, at the start, then waited to see who died. People change, though. A snapshot misses that.
So the team, led from the Harvard T.H. Chan School of Public Health, did something more painstaking. Every two years, they asked the same people the same questions about their exercise, then averaged it all out across the decades.
At 90 to 119 minutes a week of reported strength work, cardiovascular mortality was 19 percent lower and neurological-disease mortality was 27 percent lower than in the comparison group after statistical adjustment. Residual confounding and reverse causation remain possible, and the associations did not strengthen above two hours.
Cancer threw up the strangest pattern of the lot. There, the protection showed up only at the low end, a modest dollop of strength work, under an hour a week, and vanished at higher volumes.
Why a ceiling, and why such a low one? Nobody is entirely sure, and the researchers are careful not to overclaim. For the heart, the likeliest story involves arterial stiffness, the gradual hardening of the body’s plumbing that predicts cardiac trouble. A single hard lifting session can stiffen arteries briefly; sustained, regular training over years seems to do the opposite and loosen them, especially when paired with aerobic work, which is itself a known softener of arteries. For the cancer oddity, attention falls on insulin-like growth factor 1, or IGF-1, a hormone that helps muscle grow but which, at higher circulating levels, has been tied to colorectal, prostate and breast cancers. More lifting, more IGF-1, and the benefit may quietly cancel itself out. That, at least, is the working hunch.
It is worth pausing on what this study cannot do. It is observational: it watches, it does not intervene, so it can show association but never quite prove that the dumbbell caused the longer life. People who lift, the data show, also tend to be younger, leaner, less likely to smoke. The exercise was self-reported, which is to say remembered, which is to say imperfect. And the participants were overwhelmingly white health professionals, hardly a cross-section of humanity.
The neurological result, in particular, deserves a raised eyebrow. Dementia takes decades to develop, and people in its long shadow often slow down years before any diagnosis, which could make exercise look protective when the arrow really points the other way. The researchers checked for this, lagging the data by eight years and more, and the link held. Still, dementia on a death certificate is notoriously under-recorded. Caution, then.
What the study does do, rather elegantly, is map how lifting and aerobic exercise stack. Aerobic activity remained the bigger lever by far, cutting death risk by anywhere from a quarter to nearly half on its own. But strength work piled on extra protection at almost every level of aerobic fitness, right up until the very fittest, the ones already clocking enormous aerobic totals, for whom adding weights moved the needle no further. As the authors put it, the pattern “supports current recommendations encouraging both types of activity to maximise mortality benefits.”
The result is consistent with guidelines that include muscle-strengthening activity, but it should not be read as a personalised prescription or proof that one precise weekly duration maximises longevity.
DOI / Source: British Journal of Sports Medicine, 10.1136/bjsports-2025-110503
Frequently Asked Questions
Did the study establish that more strength training provides no further longevity benefit?
No. The observational association flattened at around two hours a week in this cohort, but that does not prove a biological ceiling. The cancer pattern and the proposed role of growth factors are hypotheses that need further testing.
What amount was associated with the lowest mortality in this cohort?
The lowest all-cause mortality estimate appeared at 90 to 119 minutes a week, where mortality was 13 percent lower than in the comparison group. The study cannot determine whether that amount caused the difference or is best for an individual.
Is lifting weights as good for you as cardio?
Not quite, according to this research. Aerobic exercise remained the stronger protector, cutting death risk by up to nearly half on its own, while strength training added a smaller bonus on top. The lowest risk of all came from doing both, suggesting they work best as a pair rather than rivals.
Can this study prove that lifting weights makes you live longer?
No, and the researchers are upfront about it. This was an observational study that watched people’s habits over decades, so it can show a strong association but cannot rule out that healthier people simply tend to lift more. Confirming cause and effect would need a different kind of trial, which is harder to run over a 30-year span.
Editor’s note: This article was updated on September 14, 2026, to align its headline and wording more closely with the evidence and sources.