You know you cannot be but do some action, some karma. It’s part of our nature. We have to keep acting. And if you consciously take a decision and act it is different than unconsciously doing something.
So you consciously take a decision to go on the treadmill, this is an action. Otherwise you sit and you feel so restless, you keep shaking your hands and your legs the whole day sitting in your office at your table. This only shows restlessness. You are moving you leg so many times. You are compelled to do so because your body wants that circulation. You never gave that circulation time for the body so you feel restless. This is not happening as an exercise, it is not benefitting you but it is an action which you cannot stop.
So some actions you consciously choose to do, that also cuts karma.