I started serious planning for my retirement 10 years ago; About 1 year ago. I got out of bed one day and said "it's time". I worked in a high tech/high stress field and realized it was time to move on - even though I loved my job/career.
I also realized that spending time with my wife was more important. So I packed it all in about 2 months ago. I'm 58 and in excellent health and spent my days more busy than ever. Cycling, kayaking, camping, hiking, sailing...... I'm exhausted each day before going to bed.
If you can manage it - got for it, but make sure you have hobbies/activities to keep you busy. As my manager said from "tension to pension".
gerry