You have probably told yourself that more is better at the gym. Another set, another day, another hour on the squat rack.
For most of us that mindset rests on the idea that extra effort pays extra dividends.
A new 30-year study from Harvard suggests the dividend may stop climbing sooner than you think.
Around 90 to 120 minutes a week of strength training was linked to the biggest drop in death risk, and more time with the weights did not pull the number any lower.
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The findings come from the British Journal of Sports Medicine, where researchers at the Harvard T.H. Chan School of Public Health pooled three large US cohorts.
In all, 147,374 nurses, doctors and other health workers were followed for up to 30 years.
Where the mortality benefit peaked
At 90 to 119 minutes of strength training a week, participants had a 13 percent lower risk of dying from any cause compared with people who did none.
Death from heart disease was 19 percent lower. Death from neurological conditions, mostly dementia, was 27 percent lower.
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Above two hours a week, the curve flattened. No additional benefit for overall mortality was observed, the authors reported.
Doing more strength training did not keep lowering the risk.
The study is observational, so it can map patterns but not prove cause. People who lift weights every week may differ from those who don't in ways the researchers could not fully measure.
What happens when you add cardio to the mix
Strength training alone appears to hit a ceiling. Pair it with aerobic activity and the numbers climb again.
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Participants who kept up higher weekly volumes of aerobic exercise together with 60 to 119 minutes of strength training had about a 45 percent lower risk of death from any cause.
At the highest aerobic volumes, the combined benefit reached roughly 53 to 58 percent, the research team reported.
The CDC already recommends adults get at least 150 minutes a week of moderate aerobic activity, plus two days of muscle-strengthening work.
The new data suggest the aerobic half of that recipe is what keeps producing extra years once strength time hits the ceiling.
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One finding that cut the other way
Cancer death was the exception. Lower doses of strength training, between 1 and 59 minutes a week, were linked to a lower cancer death risk, while higher doses were not.
The authors did not propose a mechanism and called for more research.
With roughly 36,000 deaths tracked over three decades, the dose-response pattern is strong enough to notice. For anyone short on time, the takeaway is simple.
Two sessions a week that total about 90 to 120 minutes may deliver most of what strength training can do for a longer life.
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Hours beyond that are not harmful. But if the goal is more years, the next hour may be better spent walking, cycling or swimming.
This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.