it’s better than bitul torah, and it’s not like davening where you need to have maximum kavava. also, working out improves your memory, so you’ll remember the Torah better!
I dont see why not (as long as your hands are pure i.e. in that you havent touched parts of your body that are usually covered or scratched your scalp or touched your shoes as those things require that you wash your hands before learning any Torah)
I imagine if you’re a person who wouldn’t be learning any other time, perhaps…otherwise it seems like a real bizayon of Torah. Would you jog in the Bais haMikdash even if you were properly clothed?
Exactly what my Rosh HaYeshiva said. It puts the Torah in the same category as anything else you would listen to. The Torah is special, keep it away from the gym.
Im not sure what type of workout you do but if it is something like stationary bike or treadmill or something like that I can’t think of any issue with listening to a shiur. I remember when I used to attend the Kosher Gym years ago there were some very frum people there real yeshiva types and even some Rabbis and they used to listen to Shiurim. I recommend you ask a Sheila. What do we know we aren’t Rabbonim?!