Why older men can't build muscles fast

Ever wondered why men with thinning hairlines find it so difficult to build muscles even when younger ones stack up soon?

Researchers believe they now know why, raising hope of addressing the condition of sarcopenia - significant loss of muscle mass and function that can occur as people age.

"In order for the body to make proteins that build muscle, certain genes need to be turned on," said Donato Rivas, a scientist at Tufts University in the US.

"We noticed that older people had fewer genes turned on compared to the younger people, showing us their muscles were not responding as well to the exercise," Rivas stressed.

The researchers observed that the level of microRNAs - small RNA molecules that have a prominent role in regulating genes - was lower in the muscle tissue of the older men compared to younger men.

"One of the steps in building muscle seems to be missing in the older men, preventing them from responding to exercise as strongly as the younger men did," Rivas noted.

"It is possible that the suppression of these microRNAs is setting off a chain of events that is causing older people to be less efficient in developing muscle," he explained.

Muscle mass is closely tied to our metabolism and losing it increases the risk of developing metabolic diseases like Type 2 diabetes and cardiovascular disease.

The findings will appear in a forthcoming issue of FASEB Journal.