Cycle Training Wheels

I attended a spin class with my wife. I've been wondering if I would be able to ride a bicycle again. I got into the saddle and pedaled and did my best to follow along with the spin instructor. I definitely still have some aerobic issues, sometimes my lungs will start burning way earlier than I think they should. I had a little bit of back pain. The session lasted 45 minutes and I stayed to the end. My core is still a little weaker than I would like it to be. I tried the aero position and was able to maintain it for a few minutes with a little discomfort. Again, this inspires hope that I may indeed participate in an Ironman triathlon.