Well, I haven't specifically measured the levels, but yes... the change in some of my behaviors is rather indicative of a surge in testosterone. To answer your question, "All of the above."

 

Aren't you simply saying that sports make you feel good, healthy, happy, confident? And that a direct result of those feelings might be that you feel more manly?

 

Although debated, there is reason to believe that endorfines are released after a good workout. It's called the "runner's high" (wikipedia).

Aren't you simply saying that sports make you feel good, healthy, happy, confident? And that a direct result of those feelings might be that you feel more manly?

Oh, that's most certainly part of it. My point was more about my aggression, though. As people who have read my posts here probably know about me, I enjoy a good intellectual sparring match. For one, I've noticed myself engaging in such sparring in more arenas lately, places that I usually let remain calm. Another thing, anytime there is a fight on television, I simply must stop and watch. Now, I used to watch UFC all of the time while I was studying kung fu regularly, but when I stopped I sort of lost interest. Now that I'm working out regularly again, I want to see some head's getting bashed and some ribs getting broken. It's certainly a different interest, as for the past several years I really couldn't have cared less about such things... yet this behavior/interest of mine has grown significantly since I began my new routine. And yes, I'm like a 17 year old again as horny as I've been. I think I'm starting to piss off my girlfriend, because she can't keep up with my renewed/intensified appetites.