Currently I ride a 2013 Schindelhauer Viktor, gearing is 60T/30T with a Gates carbon belt (I live in the hills with significant elevation changes). In years past I rode a Bianchi Limited SL (among others) and made it through several century rides (the good old days). I don’t take any supplements at the moment but eat healthy and ride regularly. It seems for me I have slowed down with rides covering 20 miles or less (ET’s not what they use to be) but have better endurance and can cover longer distances without as much fatigue when ET is not a consideration. (I think it’s because I’m better at daydreaming now than when I was younger). I’ve been biking all my life with the most miles ridden when I was 30-45. The single-speed Viktor is a departure for me from the geared bikes I’ve owned in the past. I find it more relaxing and my head is in a more tranquil state, I am not equipped for speed and I don’t have to worry about what gear I should be in. I’m still into distance rides, and enjoy good elevation changes along the way – that’s why the 2:1 gearing. I guess you could say my biking attitude has transitioned from a competitive mind set to a recreational one. I usually ride once a day for ~10 miles but during any given week try for a 30 miler as well. I do upper body work outs 2-3 times a week along with ab work to keep this aging machine from falling apart. I turned 61 this month and feel pretty good considering … knock on wood.