Wait and see how you feel when you hit 67 - UGH.... But I just think about Robert Marchand - the guy just set a new world record by cycling more than 14 miles round a track in an hour - at the age of 105.
Robert Marchand set the first hour record in the over-100s category in 2012, then beat it himself two years later at the age of 102, when he covered more than 16 miles. While his distance in last ride was not as great as those two, the new over-105's category had been specially created for him to reflect the magnitude of his feat.