A redhead,a brunette and a blonde are standing at the seashore on the Dover coast of England and looking across the English Channel one early morning.

Being healthy young women, the red head proposes that they swim the Channel. The others agree.

It is agreed that they all will use the breast stroke as being the best energy saving stroke. (Aside - actually the dog paddle is but I'm repeating the joke word for word)

The red head dives in first and completes her swim by dark that evening. She doesn't see the others. However by later that night, the brunette comes ashore. Now the two wait for the blonde.

They wait for some several days. Finally, the blonde comes ashore. The redhead and the brunette hug her in relief.

The blonde is angry: " You guys cheated. You used your hands!".