for some reason range of motion keeps popping up as the limiter, keeping people from achieving what pros achieve. i see it mentioned in bike fit as well. but range of motion is almost never the thing that makes an athlete superior. it’s almost always the engine because, at the pointy end of a sport, everybody’s got really good technique.
the thing about the vertical forearm, it’s not range of motion limiting in my opinion (because i can do it). the problems are two: thrust + hydrodynamics + timing = the ability to keep the elbow high during the extend phase, and not many people can optimize all that; and creating a vertical forearm while leaving the upper arm horizontal requires strength in muscles you’re almost never going to use absent actually swimming that way. you use minor muscle groups in strange ways. i mean, think of any other action in life requiring this muscular movement.
so, you can’t use that technique if you haven’t developed the musculature, and you can’t develop the muscles unless you know how to swim with that technique. ergo, almost nobody does it. but, “almost nobody” does not mean top swimmers don’t swim that way. it’s not just hackett and thorpe swimming like that, it’s almost everyone in the 400m and 1500m olympic finals.
i have found one strength move you can do out of the water: you’re standing on the ground, but bent over 90° at the waist. make something like a pommel to rest your upper arm on (horizontally), and do your elastic pulls that way. maybe you’re standing behind a large, overstuffed chair and resting your upper arm on the back of the chair. something like that. this fixes your upper arm in place, and then you find out really how very weak you are when you try to pull your elastic cords.
otherwise, i wrote an article about 5 years ago called, “the high cost of good form,” which I found on our archives, but, for some reason, may not have migrated to the new architecture. it was precisely this vertical forearm i had in mind when i wrote the article. sometimes you have to swim with a temporarily slower technique in order to eventually achieve a better technique. the only way to swim with this technique is for your hand to stay near the top of the water throughout the extend phase. in the vast majority of people, the hand drifts down during the extend phase. the only way it can stay level is for your propulsion with the other hand to be solid all the way to the end of its pull, to the thigh, and for your kick, your body position, all of it, to be solid. otherwise you’ll stall.
you won’t be able to swim an entire workout like this. you’ll swim parts of a workout like this. but every week you’ll be able to swim more and more of the workout like this. the nice thing about practicing this technique is that you have to fix everything that’s wrong with your stroke, from your fingertips to your toes.
now, keep in mind, it is my view that creating this vertical forearm isn’t really about propulsion, at least, it’s not during the act of creating the vertical upper arm that you’re getting propulsion (you’re getting some, but, not any more than you would be getting swimming with a different technique). the point of the move is to create, as quickly as possible, a pulling surface horizontal to the direction you’re swimming. you’re creating a bigger pulling surface, and you’re creating it early in the pull phase, so that when you start your pull you’ve got that big “paddle” pulling more water for a longer distance. so thinks me. i might be wrong. but that’s been my view ever since i started to wrap my brain around the hackett/thorpe way of swimming earlier this decade.