Just for grins, downloaded an app called Quick 7, which has a short, intense workout with a number of different exercises. And as an in-app (free) purchase, you can get Quick 4, an even shorter, tabata-based (I haven't looked up what that means) workout that takes four minutes.
I've been thinking I need to get out of my chair more often during the day (incontestably true), and thought it might make a nice break to do that workout every hour or so to enforce getting up. A five-minute break doesn't seem bad.
Well, this morning I tried it once, just to see. And granted, I wasn't holding back during the exercises. But man, I was really tired at the end. Not "I know I just pulled something"-tired, but oof, was I feeling it. Maybe I'll do it once more today, but as an hourly break? That ain't happening anytime soon, if ever.
I'm almost afraid to try the Quick 7, now. But we'll see.