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Group Exercise: MIT gyms offer group exercise classes throughout the day. You need to purchase a pass to join these exercises, but there is one free session at noon Monday through Friday that everyone can attend. Just show up 5-10 minutes early to make sure you get a spot. Also these sessions tend to be more crowded at the beginning of each semester.
Community Wellness Classes
These are classes offered through MIT medical, mostly yoga and pilate type of classes, and they generally cost some of amount of $$. See complete list of classes at http://wellness.mit.edu/classes/wellness/index
In addition to the more regimented athletic activities, MIT has many facilities for you to use from the Olympic-sized swimming pool for laps to squash courts, a multipurpose rink, basketballs, badminton and volleyball nets, and our very own sailing pavilion (highly recommended to take the sailing class so you can sail whenever you want) which are all free!
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