I'm a cyclist too and restarted earlier this summer after quitting drinking. It's going to take awhile to build up the aerobic conditioning and strength. I started with a pretty good aerobic base,I quit drinking last summer and did a lot of walking with a backpack for a trek to mt Everest base camp this May. But the biking was another level of aerobics and different muscles. Start slow and just keep building on that. Oh, I'm a 58.year old guy so if.you're much younger you'll probably get up to speed quicker but don't expect to jump on the bike and be where you were before.