Well... I'm a fat b*****d, out of condition (8 years as a computer geek) and I suffer from M.E. (although I do have youth on my side).
I managed to pump my Career from practically empty to full in about 20 mins. Sure, I was knackered but it wasn't _that_ bad.
If you're young and relativly fit, sod a bottle and buy a pump. When you get old and worn out, sell it and buy a tank
The plus side to a pump is it gives you a good work out - who needs a gym
David.