Woah..... reading and exercising, that's super cool. I'm not particularly a fan of audio books though and when I'm reading, I give it my full attention because my imagination just gets to work unperturbed.
I do exercise without music most times, i feel it's actually unhealthy to get unknowingly dependent on some things as I've indeed met people too who can't do stuff properly without music present.
Thank you for dropping your two cents on this, it's highly valued.
Might I ask if you got to finish your book at the gym yesterday though?.