Too Much or Too Little?

How do you tell someone to not over do it?  When is Too Much or Too Little not good?  On the one hand, mom wants to do things and I want her to be able to do them.  On the other, I want her to rest and not to overdo it.  How does one who is sick with Cancer find this balance?  I want to take mom to the mountains to soak in the hot springs... but I know she doesn't feel up to running around.  The pool will feel good and maybe make her feel better... but when someone is too tired and exhausted how do you convince them that doing some things will actually make them feel better? 

I'm not a good gauge of this level of activity because I go and go and go.  And I know that when the time comes for me I'll drop dead of a heart attack in the middle of going and going and going, or I'll just sit down and won't get back up.  I just can't imagine not being able to do that right now.  And for this reason it's hard for me watching mom go through this illness. I know she is just like me in the sense of go go go... but she also likes to stay home and be a homebody at times.  Just not all the time!

Striking the balance between rest and excersice is not something that western doctors talk about.  All we get is, "do what you feel up to"... and what if "what you feel up to" is smacking them for being vague and stupid?  If I can give any advice, think about how you would handle this now, when you don't have to, rather then when the time comes and you have to make the decision.  For me, I'm lucky, I have my computers... if the time comes when all I can do is sit and relax, I know enough world Web Cams that I can still see every corner of the world!!