I know lotsa people are conditioning themselves to do something they hate(cardio) with something they like(reading, watching a movie or listening to podcast). Whenever I tried it I've just lost enjoyment on reading on top instead of cardio becoming better Not like it lasted for long since I've switched from treadmill to jogging(game changer was getting a decent pair of running shoes, ended up going with Saucony Endorphine from nearby running store)
If you can handle 40 minutes on a bike I feel like you're pretty good on cardio! Try rowing anyway, see if you like it(Few judo folks do only rowing in my gym, told me works better for judo movements so it's hitting 2 birds with 1 stone basically).