The Strength Training Sweet Spot: Why 90 to 120 Minutes a Week May Be Enough

When it comes to lifting weights, more is not always better. A large new study suggests there is a clear sweet spot for strength training, a weekly range that appears to deliver most of the benefit for a longer life without the need to spend endless hours in the gym.

The findings, published in the British Journal of Sports Medicine, point to 90 to 120 minutes of strength training a week as the ideal amount. Beyond that upper limit, the researchers found no additional gains when it came to the chances of living longer.

A large and long-running study

The strength of the conclusions rests on the scale of the research. The study drew on data from 147,374 participants, made up of 31,540 men and 115,834 women, some of whom were followed for as long as three decades in total.

Over that long period, the researchers tracked 35,798 deaths, a large enough number to detect meaningful patterns. The data came from well established long-term projects, including the Health Professionals Follow-up Study and the Nurses' Health Study.

What the sweet spot delivers

For people doing 90 to 119 minutes of strength training each week, the results were striking. This group showed a 13 percent lower risk of death from any cause compared with those who did little or no resistance exercise across the week at all.

The benefits extended to specific conditions as well. The same weekly range was linked to a 19 percent lower risk of dying from cardiovascular disease and a 27 percent lower risk of death from neurological disease, two major causes of illness around the world.

Even small amounts can help

One encouraging message is that even modest efforts appeared to matter, particularly when it came to cancer. Just 1 to 29 minutes of strength training a week was associated with a 21 percent lower risk of cancer death in the analysis carried out by the researchers.

A slightly larger dose, of 30 to 59 minutes weekly, was linked to an 18 percent lower cancer death risk. These figures suggest that starting small still carries real value, which may reassure those who feel they simply have no time for long workouts.

The power of combining exercise

Perhaps the most important finding concerns what happens when strength training is paired with aerobic activity. The strongest results in the study came from people who combined the two forms of exercise, rather than relying on one of them alone.

Participants doing 30 to 44 MET hours of aerobic activity a week, together with 60 to 119 minutes of strength training, showed a 45 percent lower risk of death. Those with 45 or more MET hours of aerobic activity saw reductions that were larger still.

For that most active group, the risk of death fell by between 53 and 58 percent, regardless of how much strength training they did. The pattern underlines how aerobic and resistance exercise can work together to protect long-term health.

What it means in practice

For most people, 90 to 120 minutes of strength training a week is an achievable goal. It can be broken into two or three sessions, using weights, resistance bands or body weight exercises, and still fall comfortably within the beneficial range identified by the study.

The results also carry a practical reassurance. Since no extra benefit was seen beyond 120 minutes, there is little reason to push toward exhausting routines, and the emphasis can instead fall on consistency and on pairing strength work with regular movement.

A simple message on movement

Taken together, the study reinforces a simple idea that is easy to lose sight of. A moderate and steady amount of strength training, combined with regular aerobic activity, appears to offer some of the clearest and most lasting rewards for a longer and healthier life.