First we pointed out you have more to fear from Bambi than Bruce.* Now, another misconception put to rest, courtesy of the New York Times. To wit, a cool down is apparently worthless. Or at any rate, there’s no evidence it does you any good.
…the cool-down is enshrined in training lore. It’s in physiology textbooks, personal trainers often insist on it, fitness magazines tell you that you must do it — and some exercise equipment at gyms automatically includes it. You punch in the time you want to work out on the machine and when your time is up, the machine automatically reduces the workload and continues for five minutes so you can cool down.
The problem, says Hirofumi Tanaka, an exercise physiologist at the University of Texas, Austin, is that there is pretty much no science behind the cool-down advice.
(* The mechanical shark used in the film [Jaws] was nicknamed “Bruce” by its handlers, and the “full body” version tours around museums, while “Bruce II” resides at the Universal Theme Parks and “bites at” tourists on the tour ride. From IMDB.com)