Does masturbation affect muscle building and beard growth?

We do not know if this habit has an effect on what you mentioned, but it is known to negatively impact your relationship with Allah. Masturbation is a sin that affects and corrupts the heart if it accumulates, and it comes between a servant and his Lord. We have explained its dangers, the proofs of its prohibition, and ways to quit it in previous fatwas. Therefore, fear Allah and repent to Him, and do not blacken your record with sins.