I do a lot of waling, jogging and even some sprinting, but I've never timed myself. So, for the requirement that I run 3 miles in 28 minutes I'd have to answer "Probably, but I don't know". I know for a fact I can do more than 50 proper crunches in 2 minutes because a former taekwondo instructor of mine did time me. I say "former" because they're no longer open for business. I just found a nice place to learn jiu jitsu though and I'm starting in a couple weeks. I also know for a fact that I can't do 3 pull ups in my current physical condition. I know that I really should be able to and I'm not going to make excuses for why I can't.