Stronger muscles, longer life
Being strong might predict a longer life and muscle strength seems to protect against cancer and all combined causes of death, say researchers who have followed nearly 9,000 men for over 18 years.
The researchers compared all sorts of things, including muscular strength in the upper body and legs, to the chances of dying from any cause – but particularly cancer or heart disease.
Poor muscle strength was associated with being unhealthy, but when they controlled for things like high cholesterol, fatness, smoking and blood pressure, muscle strength seemed to protect against cancer and all combined causes of death.
Muscle strength wasn’t as important for heart disease, where aerobic fitness mattered more – although someone who was strong and aerobically fit did better.
No-one’s sure why this association between muscle strength and cancer protection might exist, and this study wasn’t typical of the general population since the men tended to be better off.
Muscles can change the way insulin works and insulin may affect how cells grow. A greater muscle mass probably also means you burn more calories at rest giving some protection against weight gain – which is known to be cancer associated.