I've tried exercising to remove post-masturbation "blues" or as I'd call it I-just-castrated-myself feeling. Exercise doesn't work. The only thing that works is taking "steroids" or sleep. Sleep cures all post-masturbation issues. I find that it takes THREE days to fully recover from masturbation and there's a good reason for that. One day is enough to at least feel better.
I have had those problems in the past, I don't know what exactly changed but I don't have much of this problem any more.
Perhaps it was my past benzodiazepine use which has disrupted something in me for a time, or perhaps I had a vitamin D deficit. Anyway, vitamin D can raise testosterone, and presumably you could raise it quite a lot if some malnutrition is causing it to be low.
What certainly does work, in my experience, is a lot of supplements that work on dopamine, so methylphenidate, amphetamine, fulvic acid. As far as I know dopamine is considered to be a prolactin inhibitor, and prolactin is released upon ejaculation.
Besides testosterone prolactin levels might be of interest.