Swimming is the writer’s sport, because it is the sport most like writing. To swim, as to write, is to choose an intense state of socially acceptable aloneness. You can be a serious runner or bicyclist and still have to occasionally nod at a passerby or negotiate traffic. Swimming, however, precludes interaction with the world.

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And yet both activities also cultivate a sort of mental busyness: If, say, yoga encourages the absence of thought, swimming encourages its presence. There is no better place to unkink a complicated piece of invented logic than in the water — there is little else to do, in fact, but confront your problems. If you are an open-water swimmer, the sport also demands a particular kind of mental discipline, one in which you must simultaneously indulge your imagination while also asserting control over it. The fear and exhaustion of swimming in the ocean is not struggling against the currents or tide, but the effort it takes to not notice how dark the water beneath you has become, and then, failing that, to assure yourself that it’s only the shadow of a cloud scudding above you. Nowhere but in the sea are you so ceaselessly reminded that something you love so much doesn’t care about you at all.

-Hanya Yanagihara, "A Brisk Swim Across Martha's Vineyard"