Anecdotally... I am, but I seem doomed. I'm not really antisocial. In fact, I can become overtalkative at times when in a social setting. But, given the option, I never seem to want to 'get out' and socialize. Though, when I force myself to, I am in such a better mood for a few days. Then, back to normal, and avoiding social gatherings again until the next time.
That's how most people feel about working out. The hardest part is getting the running shoes on, but once you're doing it, it feels really good. I don't think it is unusual for people to have an averse reaction to investing in themselves, although it does look illogical from the outside.
For me, I just feel like crap. I've run a marathon before and done a lot of other types of exercise, but that 'glow' that people report having is not something that I've ever gotten. I don't feel good after a workout or during one; I feel tired, gross, and irratiable.