after heart bypass developed a shortness of breath. Rehabilitation people
told be I have to be reconditioned. Why is this so?? Never had a heart attack.
but they said my back pain was angina. The x-ray showed I had three blocked coronaries

Could be you are not taking care of yourself the way you should be, and the way they advised you. You had a heart bypass, a very compromising surgery on your entire physical system. They are making sure there will be no chance of your having another heart attack by regular exercise, medications, special diet, and counseling. Follow their regime, oneill474, to reduce your risks.

Best regards

Tick

Heart bypass surgery is very hard on the body, takes weeks (at least) to recover from. Give it time, be patient, and let your body heal. Follow your doctor's recommendations to the letter to get the best outcome. Don't push yourself, you may end up back in the hospital.