I'm one of those middle-aged guys who stopped cycling when career/family/house in the suburbs/decadent lifestyle overtook my life. Smoking, Ben & Jerry's, prime rib, etc. The inevitable result: a series of heart attacks, diabetes, and other degenerative diseases.
Cycling was my way back, and helped me prove that heart disease can not only be stopped, but reversed.
My heart is at home when I'm on my bike. (I owe the phrase to the title of a Richard Thompson song.)
RichC