Depends on who I'm with... I know a girl who would give me head so good that I ALWAYS fell asleep for 15 minutes after climaxing. Then again there are some girls I've had sex with that it never goes down... and my energy level and desire never dissipates! I just want to keep going and going and going.
When i was younger, sex always gave me more energy... I'd have sex with my girl until she passed out... then I'd clean the house, do yard work at my mom's place and change the oil in the cars. I'm not old by any means, but these days, there are very few women I want to fuck for 4 hours. If I have my way, we'd both get off a couple of times (always her once or twice more than me if I can help it) and then we'd eat something. hahaha