You'll have to walk from the airport concourses to get to the Hilton gym, but it's worth the trek if you have a couple hour layover. Below the lobby on the lower level, Hilton's fitness center affords athletic-minded travelers with fantastic cardio, strength machine, and free weight workout options.
Because floor to ceiling glass windows are the only divider between the gym and the underground walkway, don't plan on a private sweat. Passers-by can peek in on your cycling and treadmilling. Nevertheless, the top notch machinery will likely cause you to forget about the interlopers in a hurry. Pick your pleasure, it's all here except for a lap pool.
Admission costs $20/day for hotel guests and $15 for Blue Hilton Honors members. Hotel guests that are Silver, Gold or Diamond members get free access. Shorts/t-shirts are also available for purchase. The pool, sauna and steam room are free to use for hotel guests.