Hey man, I live in Chicago part time in the Lakeview neighborhood...the eastern part of the neighborhood is called Boystown. What kind of nightlife you looking for? What I love about Chicago is there is a venue for EVERYONE. You have your 20something whitebread Abercrombie bars (like Roscoes)...your thirty/fortysomething whitebread Abercrombie bars (like SideTracks)...dance your ass off clubs (Hydrate) and after hours "im here to get laid" bars (Charlies)..... and a whole list of others types of clubs (goth, latino, leather, hard core leather, sports bars, neighborhood dives, piano bars etc).
The gayborhoods in Chicago have broken in two as Lakeview has become more expensive and yuppie in the past few years. The 'new' gay area is just two miles up the coast on the red line called Edgewater/Andersonville.
If your looking for a real gym, I go to Xsport (they are all over town) and sell day passes. If your looking for a Gym With Benefits...hehe...the place to go is Steamworks on Halstead in the heart of Boystown.
When will you be there? What part of town you staying in? Private me if you have an questions.