In swimming you often want to rest yourself, and this is done by _change
of action_. It is surprising the amount of relief a tired swimmer finds
by merely changing the manner of progression; the different sets of
muscles it brings into play afford ease to those he had hitherto been
using; in fact, in long distances this is one way in which a swimmer has
moments of rest.
The greatest change is naturally that from vigorous exertion to perfect
repose, that is, floating. In order to float, keep your head well back,
and straighten your legs, which will naturally drop a little downward;
you can either stretch your arms behind your head, or if you are really
floating to rest yourself, and not merely trying to lie flat on the
water, you can cross them behind your back.
In this latter position they give increased buoyancy to the head and
upper part of the body, and you will find it also enables you to breathe
more freely, and to look around you.