Studies have shown that immediately after intercourse, there is an increase in the blood concentration of the hormone prolactin. This hormone can have an undesirable effect in the sport activities, as it reduces testosterone levels and inhibits mental activity. However, this effect does not last long, and as shown by tests, testosterone levels do not go down so easily. Thus, we can say that an orgasm does not lead to a decrease in testosterone levels in the blood.
In addition to short-term effect of sex on testosterone levels, the researchers decided to see what effect have a long-term abstinence. A study with volunteers showed the following results: Twenty men were examined within 2 months for testosterone levels and frequency of intercourse. Testosterone levels were higher in people who have a higher degree of sexual activity.
Another study showed that sexual abstinence leads to an increase in testosterone levels up to 145% of baseline on day 7 of abstinence, after which hormone levels begins to gradually decline to baseline or ranges. Based on this work, we can conclude that in order to maintain a high level of male sex hormones the optimal frequency of intercourse is about once a week, regardless of age and marital status.
It is interesting to note that the level of testosterone increases significantly when men experience sexual arousal without subsequent orgasm. For example, a 15-minute movie with pornographic content can increase testosterone levels by 100%. Another study, published showed similar results. Thus, it can be concluded, that without further sexual stimulation orgasm can significantly increase the level of testosterone. However, it should be noted that this approach is not recommended in practice because of the risk of sexual disorders such as prostatitis, prostate cancer, prostatic hypertrophy, etc.