are made in the testicles and stored in seminal vesicles and this is an ongoing process every day. The sperms stored in seminal vesicles are shed either by sex, masturbation
or by involuntary nocturnal emissions. So sperms are maximum stored for 24 to 48 hours in the body before they are shed off by the above actions. The minimum amount of sperms needed for the male to procreate is 20 million/ ml and the motility is 50% of the total sperms. The liquefactions should be within 20 minutes. These are checked in Semen analysis
done for a male factor of Infertility
Regarding your specific concern about the masturbation causing sperm loss is not correct. Even though a person masturbates he will regain the required amount of sperm within a day or two. So masturbation causing decreased sperm count
is not true. The previous answer given to the question is misunderstood by you. There are no specific ways to increase the sperm count but healthy lifestyle with good exercise and balanced diet is always the endpoint.