The swim test is one of MIT's General Institute Requirements (GIRs)—that is to say, a graduation requirement.
The Swim Test
The swim test consists of jumping into the pool and swimming 100 yards (91.4 meters) continuously. The test is done in the Z-Center pool.
There is no restriction on how you swim—you can use any stroke or combination of strokes. You can choose to do the crawl, the butterfly, even the doggie paddle. However, the backstroke may only be used in the final lap (final 25 yards).
Students can take as much time as they wish, but may not rest on the ropes dividing the lanes or the wall. Swimming must be continuous.
Most students (700+ in recent years, according to The Tech) choose to do the swim test during freshman orientation.
There is also the option to take a beginner swim class to fulfill the swim requirement. Beginner swim classes are offered every quarter. Also, some single sex swimming courses are offered.
Small Boats Test
The boat test is required by the sailing pavilion and boathouse in order to use sailboats or crew shells. The boat test is a continuation of the swim test, requiring the 100 yards of swimming from the swim test plus treading water for 10 minutes.
The swim test was instituted in 1947 as a part of the now-defunct Freshman Athletics Program. The program was one of four major recommendations of the Athletics Association Study Committee. Another major recommendation of the Study Committee was for MIT to hire a full-time professional Athletic Director.
There are many rumors about the origins of the swim test. Among them:
The son of prominent alum X drowns, prompting the alum to donate in the son’s name [...] under the stipulation that a swim test be required in order to receive a diploma. At Harvard, the rumor was that Eleanor Elkins Widener, a wealthy widow of two victims of the Titanic accident, included the swim test as a stipulation when she donated the Harry Elkins Widener Library in 1915, which is doubtful, as the Crimson’s test did not originate until the 20s. Another version of the tale has an extremely wealthy individual donating to not just Columbia but to Cornell and MIT as well under similar conditions.
The rumors are not true.
Among the other universities currently with swimming requirements are Columbia, Cornell, Dartmouth, Notre Dame, Swarthmore, Bryn Mawr, and the University of Chicago.