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I remember playing this game back in 2010-2011, and In minecraft if you found a waterfall you could actually swim it up vertically, it was difficult but possible.

Does this apply to real life to, could a human being with muscles big enough actually swim up on falling water?

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    $\begingroup$ Depends on the meaning of the word "falling". A person can swim upstream in a river, and even swim up some low weirs. A person cannot swim up the Niagara. Hint: not even the fish can swim up the Niagara. $\endgroup$ – AlexP Oct 24 '18 at 15:51
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    $\begingroup$ ...only if you had a jetpack $\endgroup$ – nzaman Oct 24 '18 at 16:12
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    $\begingroup$ what-if.xkcd.com/124 $\endgroup$ – Karl Oct 24 '18 at 16:24
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    $\begingroup$ Actually swim up? No. But it would be possible for a human to climb up the rocky wall the waterfall is going over, if the water stream wasn't so strong it would knock her off. $\endgroup$ – Cyn Oct 24 '18 at 16:54
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    $\begingroup$ For that matter, you still can do that in Minecraft. $\endgroup$ – Sean Oct 24 '18 at 21:15
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No, not really (not if we're talking about humans, and as seen in mine-craft anyway).

The fastest any human has ever swum is 2.29 m/s, this record was set by Micheal Phelps who is about as swole as any human could ever hope to be.

The terminal velocity of a raindrop is about 10 m/s. Even ignoring a whole host of factors making this nigh impossible, the water coming down is at least four times faster than you could ever hope to swim.

But lets talk about those factors.

First off you'd also need to push your own weight up (Phelps' record was completely horizontal remember), this is something most people can do simply by climbing a ladder so isn't actually a hard part.

Secondly the water coming down probably isn't a continuous volume of laminar-flow water, It's just a bunch of drops (if it is a continuous volume its probably travelling much much faster than raindrops anyway so you've still got no chance). This means that the reaction mass for each of your strokes is much lower so you get insanely low efficiency while swimming. To simulate grab a swivel chair, take it outside and "swim in the air" till you move. Now have a friend pour a sprinkler over you while you do it. You will notice both times that you don't really go anywhere.

Thirdly you'd also need incredibly coordination and balance even if you could provide the upthrust.

Your best bet is probably to try this in a gravity-less environment such as a space station.

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    $\begingroup$ ''Micheal Phelps who is about as swole as any human could ever hope to be.'' Funny because his arms look like the arms of an average untrained person of his age, and he looks like he has legs too short for his upper torso, not to say that he is weak, just wanted to point this out... he really looks like a penguin proportion wise... maybe that's actually what makes him so fast(?) $\endgroup$ – user56555 Oct 24 '18 at 16:24
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    $\begingroup$ I was using swole in a more "general fitness sense" obviously if your going for pure muscles and appearance you could do better than Phelps. Though good observations (Especially regarding penguinness) $\endgroup$ – Ummdustry Oct 24 '18 at 18:19
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    $\begingroup$ @Eries off-topic but I believe that is precisely what makes him an exceptional swimmer. There was an article somewhere that made an analogy between a swimmer and speedboats, a long body is like a long hull of a boat, arms acting like the primary motor swimming are more efficient when longer and legs are most like a rudder creating drag and stability more so than propulsion and so are more efficient shorter $\endgroup$ – BKlassen Oct 24 '18 at 20:02
  • $\begingroup$ With fins, swimmers can exceed 3.5 m/s. Still not enough though. $\endgroup$ – Guran Oct 26 '18 at 14:08
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No, for the reasons already pointed out by Ummdustry.

Other animals also can't do it. There are exactly zero species capable of swimming up through falling water.

You may be thinking now of salmon, which do swim against strong currents and waterfalls. But they don't swim through the water to climb waterfalls. They leap over those.

We humans are poor leapers when it comes to water - on Earth. In a lower gravity setting, we just might do it.

Randall Munroe, the god of nerds, has already done some research on that. In lunar gravity, Michael Phelps might be able to leap a couple meters into the air from the water. So maybe in even lower gravity, he might be able to leap over waterfalls like a salmon.

Until we colonize space, though, we'd better not swim against the current in rapids.

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