Part of it, I'm sure, is simply because I am out of shape. But even when I was doing 75 - 100 miles per week on my bike, I hated it. Whatever this mythical "runner's high" high is, I've never experienced it. There's no endorphine rush, no "second wind", not even a momentary glow of satisfaction. After I finish a full one hour of a cardio workout, about all I feel is a need to call a cab because I'm not sure I can drive home safely.
Part of it (not to make excuses) is what I'm up against now. My illness stole perhaps a quarter of my lung field from me, give or take. I also have exercise induced asthma (controlled by medication). The missing hunk of the rectus muscle of my quadricepts in my right leg make my right foot turn out after about twenty minutes of exercise, making jogging impossible and brisk walking a pain in the butt. [I'm always afraid I'm going to trip on the treadmill and end up a spectacle in front of the others in the gym. I've seen it happen to others, and I'd rather avoid that embarrassment if at all possible.]
We won't even get into what exercise does for my little lower bowel ailment.
Yes, I do it. I know I have to. I don't mind the strengthening stuff so much, but that doesn't help what needs helping. What I need is to keep my heart rate in the 130 beats per minute range for an hour. That means one hour of absolutely boring biking or stultifying walking (4.4 mph - any faster and I'd have to jog, and my leg won't tolerate that) while the televisions blast some sports competition or another and the gorillas over at the bench press pose for the high school cheerleaders wearing their newest spandex creations.
I loathe exercise.