There are quite a few older celebs this year. In the past some of the older celebs have been excused certain tasks because of ailments. I really hope that this is not the case. If the celeb isn't fit enough then they shouldn't go into the jungle.
I don't think it's so much age as physical condition... They all have a medical pre going in and I suppose if someone's BP for example, is just within normal range they wouldn't give them a task which might make it rise. Having said that, I can't think of any task which would be stress free. Which ones did Biggins do last year? I can't remember, but he most certainly didn't look as if he kept himself in trim ( bit like me!)
I don't think its necessarily age related. There was a young one a while back (can't remember their name) who was excused from a task - so not sure.
Anyway, I think the older generation are a lot fitter than the younger generation. Have you seen how much people of my younger generation drink - and what junk they eat too? No, I think the older generation are much more health conscious.