The first gym in Chicago to offer CrossFit, the full-body workout that draws from weightlifting, plyometrics, gymnastics, and pretty much every other fitness trend out there, this one reigns supreme. Why? Its 75-plus classes a week (more than anywhere else in town), thoughtful one-on-one assistance (goal-setting sessions, nutritional education, body composition analysis), and slow, safe introduction to the workout (you’re highly unlikely to pull a hamstring or pop a shoulder here). A 30-day membership costs $198.

How to: Get a 20-minute workout in your hotel room

Warm up and stretch for eight minutes. Then set a timer for 12 minutes and switch into beast mode: Do 10 air squats, 10 pushups, 10 sit-ups, 10 forward lunges, and 10 jumping jacks as fast as you can. Repeat until the clock runs out. It’ll get your blood pumping and stimulate major muscle groups—so there’s no need to bench-press the bellboy. —Justin Marcis, owner of Windy City CrossFit