Answer: Due to the reduction of testosterone, there is a reduction in bone mass, hair growth etc except for an increase in body fat.
Explanation:Testosterone is a hormone found in all men and it is important in the formation of bone mass, hair growth and production of sperm.
The production of testosterone reduces as the man grows older and many other noticeable changes such as hair loss, reduced bone mass, erectile dysfunction except for the increase in the body fat of a man.