In fact, although the growth of male body hair needs the support of androgen, the amount of body hair has nothing to do with the level of androgen, but is determined by the sensitivity of skin hair follicles to androgen and is inherited by individual genes.
For men with less body hair, adding androgen will not increase body hair, nor will it thicken body hair.
Secondly, strictly speaking, fitness will not improve your normal androgen continuously, but maintain your androgen level, or restore your decreased androgen to its original high level.
Male hormone secretion reaches its peak at the age of 30, and everyone's body hair has been fully expressed according to the genetic code during this period. Some people have less hair, others have more hair, and most of them are in the middle. This is the difference of individual appearance, not the reaction of androgen level.
With the growth of men's age, skin hair follicles will become more sensitive to androgens, so although androgens are declining in their 40 s, their body hair will increase.
Therefore, exercise will not have any effect on body hair and beard.