How do you know when enough is too much?

I know what you mean.
I now try and stick to about 80% of what I think I am capable of, and then tend to get it about right, most times for me.

Are you having sufficient rests in between jobs? That may well be the key.

I'm afraid I'm not very patient with myself and tend to just push on until I get finished. Maybe I need to structure my approach to who I am rather than who I think I am.
(younger and fitter). I just get frustrated ..... grrrr.

Charleygirl's advice is good. Or similar - work for eg 10 minutes, rest for 5, another 10 etc. Or whatever you find suits you.
That's wha I do now.
Also vary the type of activity.

I find I stop when I begin to feel tired or stressed doing a particular task, whereas before I would grit my teeth and keep going until the job is done.

And as already suggested, programme in rests between tasks.

I did too much today ( just getting better from chest and sinus infection lasting weeks) went out for lunch with DD2 and then helped her to do some early Christmas shopping.All took hours, and now feel exhausted.Have to learn to pace our poor old selves.

I've adopted that word, Pace, it's certainly what gets me through! I used to rush about like a mad-thing because that's what life used to be like and I couldn't break the habit. But a nasty long-lived bug earlier in the year really taught me a) that it takes longer to recover now and b) that it's better to pace myself: do a bit, stop a bit...

I went Christmas shopping too (some presents need to be posted off) and by the time I got to M&S foodhall late afternoon I felt sick and shaky. However, when I sat in the car I felt better and after getting home and having a cuppa I feel revived enough to stick my M&S ready meal in the oven.
It doesn't seem that long ago that I could charge from one end of the shops to the other.

I find it very hard to adjust to this new me-I am hoping to return to where I was in June but perhaps that is a forlorn hope. I've spent my life always trying harder - that's how you achieve things. Instilled in me many, many moons ago by my father, I'm so frustrated that my trying isn't working as well as I would like. I also feel guilty if I sit around.

ok with most things....shopping drains me....have to plan different parts of town/city for different days and concentrate on small areas .....shopping malls are the worst

And I thought it was just me.

I'm glad I read this thread.

Me too jings, I thought I was being a bit lazy because I have to have sit downs and tea breaks!

It's me too. I never liked shopping very much but now I'd rather surf the net for Christmas presents for the GC. As for housework, my back gives out after about ten minutes and I need a sit-down which tends to extend beyond the next ten minutes. A series of sinus infections on top of polymyalgia make me even less enthusiastic about vacuuming than I used to be.

shopping malls are the worst
yes, it was a shopping mall, I did a couple of places on the outside first then intended to whip into JL and walk to the other end, looking and shopping as I went along.
I just managed to drive get to M&S and buy nothing (except food)

Poor old us.It's just getting used to doing less at a time, the spirit is willing etc.

I'm the same - rather relieved it's not just me! I'm sure DD thinks I'm putting it on sometimes when I insist I can go no further without a sit-down...

It all sounds horribly familiar to me but as I suffer from M.E. it usually means days of rest required if I do just that little bit too much and that is so variable that you can't work out how much can be done on any particular day before you are scuttled.
I think you just have to do the 'mind over matter' thing i.e. you have to 'make up your mind that it really doesn't matter' so that if you really want to do something you are prepared to 'pay the bill'.
If you Google 'the spoon theory' that puts it so much better than I ever could and is the same for a whole raft of health problems - and probably age problems too!

Tomorrow I'm going to the Cake and Bake show at Event city in Manchester with my ds! Walking about for several hours with a bad back, and two dodgy knees could be interesting and it may be stupid, but he needs support and I'm it!
I'm having back treatment this afternoon and I've got lots of painkillers!

I work like a lioness hunts . If you've ever seen a lioness hunting, she runs like the clappers and if she can't catch her prey, she just plops down wherever she is and has a stretch and a lie down for a while, till the next opportunity to do some "work" comes along.

I think part of the shopping thing is that it's so boring. I walk round JL, M&S, etc,etc and just can't get excited about any of it. In September we walked 10 miles a day in Tuscany and that was totally different!

And in most towns the shops are now all the same

And doing soft play with the grandsons is great! Sorry enough now!