Exercise can apparently lessen the rate of cancer cell growth and even help prevent its recurrence.

It's really obvious bc or whatever strikes us very differently AND it effects is very differently.  My daughter explained her having "lost her mojo" one time when she was down and out : and that's how it feels to me. I'm finding it more difficult to be UP these days snd cheering others up. Maybe it's maturity and general ageing at 67  
whatever it is I hope to get back more enthusiasm for life again soon.