Stumbled upon this snap a while ago. Was looking for Tour de France history, and this smoking pic turned up. Apparently the riders in 1920s believed that smoking aided in respiration.
Reminded me of my college days- marathon running, in perticular. I have run 2 half-marathons, and I would never reach the finish line in it wasn't for the pack of cigarettes I carried. They screw our lungs all right, but lungs do get a bit responsive when heavy physical excertion is being done. Tried to know why- no success yet. let me know if you have any idea.