Hi
I think the older you get the higher the odds become against you- that's the reality. One of my customers is 55 and still works for British Gas digging up the road for gas leaks. Out performs the 2 youngsters working with him. But he's the exception.
I am 58 and was fine until I had a prostrate op last year - only working on half steam now and its a real struggle. I doesn't seem to get better with time either. Also have high blood pressure and still haven't found a tablet that works for me. Would I make my boss money window cleaning? Doubt it.
One of my customers had a prostate op 3 years ago, and has now taken early retirement as he could no longer hack it.
How your health holds up is what it's all about. I am a little overweight, but don't drink or smoke. Can I see myself working for the next 10 years WFP? Doubt it, but I have no choice but to carry on. There's no end in sight. Please don't get me wrong, I enjoy being out in good weather, talking to customers and doing a good job is very personally rewarding, but poor health can be a real downer.
This is why you take someone on in a trail basis for 3 to 6 months, to see how he performs. Older guys tend to be more reliable, but younger guys have the stamina as has been said on previous posts.
Spruce