You probably know someone who swears by the gym. Maybe you have even tried to build a strength routine yourself and wondered how much is actually enough.
Most people would rather have a clear number than keep guessing.
A new analysis of nearly 150,000 adults in the British Journal of Sports Medicine suggests that number sits between 90 and 119 minutes a week.
People who hit that window had a 13 percent lower risk of dying from any cause.
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More was not better. Going above two hours of strength training a week added no extra protection on top.
What the 30-year study actually found
Researchers at Harvard T.H. Chan School of Public Health pulled data from three large US studies.
These were the Health Professionals Follow-up Study, the Nurses' Health Study, and the Nurses' Health Study II.
Together they tracked 147,374 adults, with an average age of 54 at entry. Every two years, participants reported their exercise habits. Follow-up ran for up to 30 years.
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The 90 to 119 minute window was also linked to a 19 percent lower risk of dying from heart disease.
The same window was tied to a 27 percent lower risk of dying from a neurological disease.
Cancer looked different. The lowest death risk showed up at much smaller doses, roughly 1 to 59 minutes a week.
The extra edge from pairing weights with cardio
The strongest numbers came when people did both strength and aerobic exercise.
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Participants who hit 60 to 119 minutes of weights plus a high amount of cardio each week had roughly half the all-cause mortality risk of those doing neither.
What this study does not tell you
This is observational research. It can show a strong link between habits and outcomes, but it cannot prove that strength training itself causes the lower death risk.
The researchers also noted several limits. Participants reported their own training time, which is not always accurate.
The study did not capture how hard the sessions were, how long each one lasted, or activities like calisthenics and Pilates.
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How this fits with current advice
The weekly window lines up with long-standing US guidance.
The Centers for Disease Control and Prevention recommends adults do muscle-strengthening activity on two or more days a week, on top of 150 minutes of moderate aerobic activity.
In practice, 90 to 120 minutes a week is reachable for most people.
That is roughly two sessions of about 45 minutes, or three shorter sessions of about 30 minutes, built around the major muscle groups.
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This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.