second the motion on wigstheone suggestion of
O'Hare Hilton Health Club.

If you are HHonors member, gym only costs $5, good equipment, hot, high pressure showers.

Only about 7 minute walk from UA B Concourse another 5 min from C Concourse.

If you like , no make that love garlic, the salads at Wolfgang Pucks in B Concourse (I think near B4) are tops.