If you really want to do the most you can to build your air compacity up you should do some reading of bicycle sports training books. The racers and their trainers have studied all the ways to increase your " air " extensively. Just because you don't race, that doesn't mean you can't use some of their techniques. I've found that even if I'm not actually training, just knowing about the lingo helps. i.e. I'm not gasping for air, I'm increasing my air intake power output ratio! That's how racers talk, and it works.