For some, a workout is not the most pleasant of experiences. I choose racquetball for most of my exercise, since it adds some competition and camaraderie to the task. I KNOW I should be in the weight room, but after getting out of the habit of daily workouts for school sports, I have not gotten back into it. Don't tell my doctor.
When I saw the headline reading, Top 5 Stockhausen Klavierstücke For Working Out, I was curious. First, I have not heard much he has written which I've heard all the way through. (Though the piece below, Oktophonie, is pretty cool.) Most of what he wrote is NOT radio friendly, but Oktophonie is one that needs to be experienced live, as much as listened to. That...and it's over an hour in length. Stockhausen's music is an acquired taste, like brussels sprouts or kimchi. (Thomas Beecham is said to have been asked if he had heard any Stockhausen. His reply? "No, but I believe I may have trodden in some."
I have spoken with some who love the challenge of unraveling his manuscripts and others who have called at least some of his compositions unplayable. Wherever you land on the spectrum, or if you maintain a firm ambivalence about it, the five pieces mentioned in this list will surely get you some exercise...either motivating you to work out, or getting your heart rate up because you ran the other direction.
https://www.youtube.com/watch?v=ePBB-NO8vKg