I know it has for me. Cycling is the only type of exercise I actually enjoy, and being in my mid 50's and overweight, it's best that I keep it up. Had I not taken up cycling about 10 years ago I'd likely be really worried about a heart attack by now.

And OP: Good job and keep going. But as others advised here, take things slow and best if you do it under doctor's advice. But you'll get there.