I'm fitter now, at 73 (last Sunday) than I was when I was 48. I took up tennis again then - I couldn't keep it up while going to work & raising a family.
I wouldn't want to be 60, as I was then diagnosed & was trying to understand a diseased that would cause my death through lots of complications. Nor 69, as those complications set in.
At 65 the church organist left & I resorted to leading the music with my treble recorder, & started to learn keyboard & joined a choir. That has enabled me to play to lead the worship, & I sing regularly with two choirs.
At 73 I have all my faculties, & play tennis & table tennis; preach the Gospel & lead Bible studies & worship. Also my wife is well & active. And go back 3 years & I wouldn't have 2 of my grandchildren. So 73 it is - thank you, Lord Jesus.