Dance Dance Revolution?
That said, there's a mostly working .sm to .ssc converter (it's still got a couple edge cases around punctuation in titles), as I had to migrate the simfiles to something with named properties anyway to get reliable data out of them.
This, and the seeder script (which I wrote using a bunch of fetch requests in order to also test a bunch of my frontend logic, before Node started shipping with that) that I used to seed all the DDR arcade tracks into a db, were actually my first experience with Deno. It's been my go-to experiment tool pretty much ever since.
If anyone's curious, it's under my github (same username) at step-step-recollection. (And ...recollection-scripts, and ...recollection-ui. Annoyingly I never got to experimenting with server-side rendering on it, so that's also a separate repo.)
I have to say that physiological randomness of this kind is one of the main "use cases" for structured routines.
Before I lived such a structured life, I also felt like I would enter various activities with a roulette wheel of emotions. Which I found to be a big problem! But these days, and due to my structure, a) my mood is highly stable and predictable and b) on the rare occasions when my mood deviates, I usually have a very good idea of why, e.g. deviations in sleep.
On the flip side, there are great days too. Take advantage of those and get a little more done in the gym. Overall it's about consistency of the practice, not about an individual session being great.
I'm not entirely with you about gyms in particular. Weights might just not be your thing as an individual, but "going to the gym is not fun" is often about the logistical problems of timing around gyms (peak hours, January rushes especially) and not necessarily that it's an inherently bad experience. If you're going when it's dead, it can actually be pretty great.
If you're doing it now, then yeah, it's a bad idea (and there's a separate ramble on that), but it doesn't have to be.
Broadly though, I agree with you. You'll never find me on a treadmill, but will find me on a DDR cab.