Muscle training — but not too much — reduces risk of disease, Japanese researchers say

The pandemic may have changed training trends forever, but there’s no ignoring the fact that staying physically active will reduce your risk of dying or getting sick. That said, how much exercise do we really need to stay healthy, and what kind of exercise should we be getting?

A group of Japanese researchers claims to have an answer.

Hailing from some of the country’s leading universities ー Tohoku, Waseda, and Kyushu ー, researchers recently found that exercising muscles for up to 60 minutes per week is optimal for preventing serious diseases such as cancer and reducing the risk of death. However, they cautioned that overtraining can be ineffective or even risky.

The results support the opinion of the World Health Organization, which recommends that adults engage in moderately intense strength training at least twice a week, along with moderate aerobic exercise.

The data showed that, compared to people who did not exercise, people who did muscle-strengthening exercises had a 10% to 17% lower risk of dying or developing conditions such as cancer, cardiovascular disease or type 2 diabetes. The risk of death or developing these diseases was lower in this group of people regardless of whether they did aerobic conditioning exercises such as walking or running.

Furthermore, muscular strength training over a period of 30 to 60 minutes per week was found to be more effective in reducing the risk of death, cardiovascular disease, and cancer, reducing the chance by 10% to 20%.

The findings showed that muscle-strengthening activities were associated with a 17% lower incidence of diabetes, and diabetes risk was dramatically decreased when strength-training activities were performed for up to 60 minutes per week.

However, the researchers warned of the negative effects of too much training.

After 130 to 140 minutes of muscle training, no positive health effects were observed, with the exception of diabetes-related problems, leading experts to warn against doing such exercise more often. In fact, the risk of developing a disease seemed to be greater for those who spent more time exercising.

The researchers found that combining aerobic exercise with adequate muscular strength training further reduced the risk of cardiovascular disease and cancer mortality.

the study recommendations were published on February 28 in the British Journal of Sports Medicine, a fortnightly publication covering the science and medicine of sports.

The research group analyzed the results of 1,252 published studies from around the world that examined the relationship between strength training, disease, and death. Sixteen highly reliable studies were selected and the results were integrated to determine the relationship between the duration of muscle training and the risk of disease onset and death. The researchers referred to studies conducted in the United States, England and Scotland, Australia and Japan.