I remember once I was swimming across a lake with a friend in high school and part way through I felt just so exhausted. Like, my arms and legs just didn&#x27;t want to work.<p>It&#x27;s a bit different of a feeling than when you&#x27;re tired while running or wrestling (the two sports I played in HS) -- it&#x27;s like you just cannot move. Even in those sports I never felt as <i>dead</i> as I did trying to swim across the lake.<p>It probably wasn&#x27;t as scary as your experience, but it was absolutely terrifying, especially since -- like you said -- above water you seem fine, but under you&#x27;re frantically swimming trying to stay above water.