An analysis of data collected from the existing evidence has shown that muscle-strengthening activity for 30 to 60 minutes every week independent of aerobic exercise is associated with a 10 to 20% reduction in risk of dying from all causes, particularly from cancer, diabetes, and cardiovascular disease. The analysis however indicates a J-shaped curve for the majority of outcomes, without any conclusive evidence that the risk is further reduced with more than 1 hour of muscle-strengthening activities every week.1✅ JOURNAL REFERENCE
DOI: 10.1136/bjsports-2021-105061
The adults’ guidelines for physical activity recommend participating in muscle-strengthening activities regularly, mainly due to the known skeletal muscle health benefits. Examples of these activities include resistance band workouts; weightlifting; squats, sit-ups, and push-ups; as well as heavy gardening such as shoveling and digging. Prior studies indicate that muscle-strengthening activity is linked to a reduced risk of death, but the optimal ‘dose’ is unknown.
To establish this, research databases were searched for relevant observational studies which included individuals who had been monitored for a minimum of 2 years with no major health issues. 16 studies were included in the final analysis from an initial pool of 29. The number of study participants varied from almost 4000 to about 480,000, ranging from 18 to 97 years of age. 12 studies included both women and men; 2 included only men only while 3 included only women. Aerobic or other kinds of physical activity were considered in all the studies, as well as muscle-strengthening activities.
The analysis of the pooled data revealed that muscle-strengthening activities were linked to a 10 to17% reduction in risk of dying from any cause, as well as dying from lung cancer, cancer, diabetes, stroke, and heart disease. No link was found between muscle strengthening and a reduction in risk of specific cancer types, such as bladder, kidney, bowel, or pancreatic cancer.
A J-shaped curve was seen, with a maximum reduction in risk of between 10 to 20% at about 30 to 60 minutes of muscle-strengthening activities a week for dying from any cause, all cancers, and cardiovascular disease. An L-shaped relationship was seen for diabetes, with a large reduction in risk with muscle-strengthening activities of up to 60 minutes a week, after which a gradual tapering off was observed.
An analysis of aerobic and muscle-strengthening activities combined revealed that the risk of death reduction from any cause, cancer, and cardiovascular disease was even greater when these 2 activity types were combined.
