I used to believe that the only worthwhile exercise was the kind that involved working hard - running quickly (not jogging); lifting weights (heavy); and calisthenics with a vengeance.
How horribly mistaken I was.
The truth is that any movement - provided it's not going to give you RSI - is good for you. More than good, it's invaluable.
If, like me, you have a sedentary job, that job is killing you. Sitting at a desk causes all kinds of problems: you get a hunched-over posture, your stomach muscles go slack, your muscles - including your heart - get weak, and your circulation suffers.
We evolved to move, not to sit around.
More: it seems our brains may have evolved specifically to get us moving around.
And because of this, moving is arguably beneficial for the brain as well as for the body.
It doesn't have to be anything dramatic.
Make it your goal to get up from your desk and walk around (if possible) for a minute or so frequently throughout the day.
Shoot for, say, doing that every twenty minutes or half hour.
You'll feel better for it, you'll be healthier for it, and your brain might even function better because of it.
Do you need any more reason than that?
How do you put on your socks and shoes?
What's with all the pullups, Jack?
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Note: this is purely my own opinion - and get your doctor's advice before attempting anything that might be strenuous for you personally!