Re: Aikido: Most Physically Involving?
I don't know about aikido being any more physically demanding than other arts - there's too many variations and levels of practice/exertion to form any sort of balanced opinion on my part.
What I have noticed though, personally speaking (typing?) is that I've become somewhat 'activity specific' with regards to fitness; I take quite a lot of ukemi in an average session which doesn't bother me too much - but put me in another physical activity for a similar length of time (even one that is supposedly less demanding) - and I'm exhausted!
I suppose the flip side of that is also true - take someone who is fit but not used to breakfalls, say a swimmer/runner, and get them to fall down and get up many many times in quick succession - and they're exhausted in no time.