At the end of last year, my recumbent bike died, so my cardio workouts now tend to come exclusively via elliptical (ideally, five times per week).
Previously, some of those 150 minutes of cardio were consumed by reading on the recumbent bike, but I can’t really read on the elliptical (I envy those who can).
So I’ve begun filling some of that otherwise mindless time with podcasts. Two favorites are Jonah Goldberg’s Remnant and Russ Roberts’s EconTalk podcasts.