I set my mixer to mono and your backing track sounded fine to my ears. I think you'll be fine except bass might be a problem in the gym. You have a lot of really low bass frequencies in the mix and using something to dump them out steeply from about 60 down would be a good cautionary measure. If you're working with RB, try using the 10 band eg and pulling the 31 slider all the way down. Experiment with using more than one instance. You probably won't hear much difference in your monitors, but it should help when you play it at the gym.

I'm in agreement with the others that it's a good sounding backing track. On a personal preference note, I would change the drum track in places to get rid of the stutter sounding pattern, but that's just me (and DannyC lol).