Okay guys you need to try some more sports. I agree that rugby looks like a genuinely difficult sport but I've played baseball and it really isn't that hard. If you want a real challenge try folk style wrestling or rowing. Doing a two kilometer ergometer test is the most painful thing you can imagine. Also, in wrestling when you are on your back but not quite pinned it is incredibly hard work. I have found that life or death, fight for survival mindset several times. I never found baseball quite so intense...