Lots Of Speedos On Swimmers.

[PSDave]

You hit the nail on the head. Jammers are just long legged lycra suits. The knee length competition suits are specially designed and constructed out of special materials that can actually improve a swimmers performance. The problem - all that technology is cost. Those suits can cost 4 times what the brief cut suits cost. Most schools or swim teams don't have it in the budget. They seem to only show up at events like the Olympics where the makers can get world wide recognition of their suits so they donate them. (subliminal commercials)