Season 3 Episode 14 "MythBusters Revisited" during the "Who Gets Wetter?" segment.
Grant and Tory re-did the "walking vs. running in rain" myth and to avoid having sweat from contaminating their results when weighing the worn clothing, they had to wear full-length rubber body suits from an, ahem, adult's only boutique. Cue giggling and snickering.
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