When is too old for Plastic Surgery?

Hi - I'm 58 and had an arm lift 4 months ago and was out of work for 2 weeks.  I had my tummy tuck 2/24 and will be going back to work this week (4 weeks).  Not sure what I'm going to do next.  My advice would be to make sure you're muscles are in the best shape you can get them in before the surgery - exercise, exercise, exercise.