Strength training 90 minutes a week was linked to aging 4 years slower

The case for strength training is well-documented. Among decades of research, it’s tied to better metabolism, stronger bones, and more years of physical independence. Now, a new study goes further: resistance training may change the rate at which your body ages at a cellular level.

The findings

Researchers at Brigham Young University analyzed data from over 4,000 U.S. adults between the ages of 20 and 69, measuring telomere length as a marker of cellular aging. Think of telomeres as the protective tips at the ends of your chromosomes — they shorten naturally as your cells divide, and the shorter they get, the faster your body is aging. Higher risk of chronic disease, cognitive decline, and early death all follow from that decline.

Adults who strength trained regularly had significantly longer telomeres than those who didn’t. At around 90 minutes per week, or three 30-minute sessions, participants showed telomere length associated with roughly 3.9 fewer years of biological aging on average.

One limitation worth noting: training data was self-reported, meaning participants logged their own exercise habits rather than having them tracked or verified externally. That introduces some room for error. But the pattern held even after researchers controlled for age, sex, income, and other lifestyle factors, so they were confident in the direction of the effect.

What this means for you

Most longevity research on strength training focuses on disease outcomes like sarcopenia, or cardiovascular disease. This study looks upstream of all of that, the cellular processes driving aging itself. The benefits, in other words, aren’t just functional. They may be written into your biology.

The threshold was more accessible than it sounds, too. Participants in the study weren’t required to follow a specific program or train at a gym. Weights, resistance bands, and bodyweight movements all counted equally.

What the data pointed to most was consistency over time, not session length or intensity.

A few practical notes:

• 90 minutes weekly, spread across two or three sessions, was associated with the strongest effect.
• Bodyweight-only training counted. The barrier to entry is lower than most people assume.
• The relationship was linear, meaning even 20 or 30 minutes a week is moving the needle.

Most fitness advice treats strength training as a tool for how our bodies look or perform. These findings suggest something more fundamental: it may be one of the most direct inputs we have into the pace at which the body ages.