you know what, the Marine Corp is not the only branch of service that pays attention to physical fitness, even though we like to tell ourselves this. Well some of this athletes have years of experience and might have been professionals if they were not in the military. I will tell you that the Air-force has some of the best distance runners in the Armed Services. You just have to open your mind sometimes. I have to admit it but the Airforce so far has won a fear share amount of the Armed Service competition while the Marine Corp fights with the Navy to place third. The Airforce also has a pretty athletic program. That is why we need people like you to go out and represent the Marine Corp in certain events. I plan to join the cycling team if there is one. I have been training here and there when there is the opportunity, but really you need between 8,000 and 10,000 base mileage to do well in a competition and i don't have the time right now. But if you are interested it is something you can always train yourself and in couple years you will be fit.
You right, you get better a things like cycling as you get older, the reason being that your body gets matured with the sport and then it is like part of you. So years of training will definately get you where you like to be.