yes the gym is rather small on campus, but i would be willing to be your personal trainer for the amount you would pay for a gym membership..j/k there is a new aquatic center + gym for 10$/month with a group membership from midwestern. Just wait until or ask student services about it in the fall.
The local city of Glendale recreation center, Foothills Recreation & Aquatic Center, offers yearly memberships to students for $100. You will probably get more info at orientation in August.You can look at the facilities at www.glendaleaz.com/parksandrecreation.