The rules are very specific. See below. They probably want to update their pronouns for the 21st century though.
"The swimmer must, as soon as his feet touch the ground, land as directly as possible.
(WALKING 200M ALONG THE SHORELINE TO CAP GRIS NEZ IS NOT PERMISSABLE)
He must then return immediately to the water
Where he may stand or sit for up to 10 minutes. During this time he must not be touched by any person, but may be handed food, grease, medicines or swimming apparel to be administered by himself. He must then, in agreement with the Observer, make the most direct and reasonable way towards water deep enough in which to swim, and commence swimming. In all the above conditions, the Observer’s ruling will be final, subject to official ratification by the Committee. The time spent before the return swim starts shall be added to the time of the subsequent crossing."