Swim Myth #4......Busted!

RE: Swim Myth #4......Busted!

Former Member — Thu, 05 Aug 2010 11:20:29 GMT

The part that has me confused is that the longer the lever the larger the force at the shoulder has to be to generate the same force at the hand. If you hold force at the shoulder constant then the amount of propulsive force drops as the lever gets longer. The distance parallel to the direction of travel from the front of the stroke to the back is the same, at two arm lengths, even though the straight arm pull travels a longer circular path the component perpendicular to the direction of travel doesn't provide forward propulsion. It seems to me that any advantage in a longer lever has to come from different timing. Either that or the greater downward force in the front quadrant lifts the body enough to reduce drag, and I'm dubious about that. Another explanation might be that for some reason the straight arm swimmer is able to generate higher forces at the shoulder than the EVF swimmer. I'm not sure why that would be but it seems plausible. My intuition still tells me that the straight arm swimmer is benefiting from a difference in timing, possibly spending less time in the non propulsive front quadrant. Isn't it generally the case that swimmers with a non-EVF pull have a higher stroke rate? Lindsay, Do not underestimate the importance of lift to a swimmer. Lift occurs from three sources. First, the outstretched arm in front (and body), so long as it has enough velocity (Bernoulli's principal). Second the downward force of the hand/forearm as it transitions from forward to rearward motion and drops down. Third, from the kick. Every millimeter of lift of our bodies in the water decreases drag significantly. How do I know? Just jump into saltwater or put on a wetsuit and the additional lift (buoyancy), likely measured in mm, enables us to swim faster. Gary PS...even the deep arm puller doesn't really pull in a circle. Once the hand reaches the 6 oclock position on the circle of the hand's motion, it slides up into the circle to maintain a more direct path rearward, then releases upward and forward by sliding with least resistance when it reaches 9 oclock. Meanwhile, the wrist dorsiflexes to maintain the propulsive drag force during this maneuver. There is no reason for the hand to push up toward the surface, effectively pushing one further down in the water.

RE: Swim Myth #4......Busted!

Former Member — Thu, 05 Aug 2010 11:06:19 GMT

Here's something to consider: Practice both the EVF and more traditional deep pool stroke. Then, when you race a distance where you have a decent chance of dying, be prepared to switch stroke styles as needed to recruit fresh muscles. A veterinarian friend whose father was a vet at Churchill Downs told me that when a race horse begins to tie up at the end of the race, smart jockeys are able to get the thoroughbred to shift gaits slightly and finish strong. He (my friend) watched me die a horrible death in the final 10 meters of a 100 meter freestyle once and said it was too bad I had no other gait I could switch to. In practice lately, when my arms get super tight during difficult sets, I have found that switching to EVF gives me a little extra reserve capacity. Who knows? Maybe the best stroke is neither one nor the other, but the possibility that we can switch back and forth as exhaustion hits. Sort of like rotating crops to avoid a crop failure... I will try this at Zones and see if it helps. What Jim is talking about makes alot of sense and really works. Two great examples of swimmers who use or used this tactic are Nathan Adrian who switches from shoulder-driven freestyle to a straight armed, body-driven freestyle in the 100 meters for the last 10 meters or so. Also Michael Klem from Australia switched from flutter kick to dolphin kick on the last 10 meters of his 100 freestyle (and set the world record leading off the relay this way). Both are ways of increasing stroke rate when fatigue is grabbing us by the ___________s. Gary

RE: Swim Myth #4......Busted!

Former Member — Wed, 04 Aug 2010 07:28:58 GMT

Thanks for the testimony. And what about the measurable impacts? Time? DPS?

RE: Swim Myth #4......Busted!

Former Member — Wed, 04 Aug 2010 05:59:51 GMT

i tried doing EVF the whole time at practice and i can tell you that.... 1. it increases straight horizontal pulling distance 2. it keeps your shoulders wide... keeping your posture better and your entire body in a better position 3. Its Def better for your shoulders to swim this way edit: two other good reasons: 1. stand up and stick your arm straight out in front of you... imagine this is the arm that is midway through the pull.... now the other arm should be approximately midway through the recovery... put this arm in the position it should be in (high elbow), feels weird... your body feels most natural when the other arm is straight out (straight arm recovery) and this would put your body practically vertical with respect to the surface of the water now try it with your elbow at 90 degrees and your shoulder at neutral... see what im getting at? 2. Much more efficient... a lot of people are talking about speed is #strokes x DPS... and efficiency does not factor into this but is very important

RE: Swim Myth #4......Busted!

Former Member — Tue, 03 Aug 2010 14:09:14 GMT

its the same as pushing a car up a slight slope (down and back stroke) with a powerful engine as opposed to pushing the same car on a flat plane (pretty much straight back towards the feet) with a slightly less powerful engine.... the latter wins applied to our bodies it means we are using less energy to go the same distance

RE: Swim Myth #4......Busted!

Former Member — Tue, 03 Aug 2010 14:08:41 GMT

i did not read every single reply but i am hoping that someone mentioned that EVF means your hand is pulling straight back towards the feet as opposed to down/back with a straight arm I hope so cause it's the biggest benefit that I see. Making the Effective Pulling Range even more 'effective'

RE: Swim Myth #4......Busted!

Former Member — Tue, 03 Aug 2010 14:06:11 GMT

i def think it increases DPS and i def think it facilitates healthier shoulders as it puts the rotator cuff muscles in a mechanically advantegous position

RE: Swim Myth #4......Busted!

Former Member — Tue, 03 Aug 2010 12:56:17 GMT

The part that has me confused is that the longer the lever the larger the force at the shoulder has to be to generate the same force at the hand. If you hold force at the shoulder constant then the amount of propulsive force drops as the lever gets longer. The distance parallel to the direction of travel from the front of the stroke to the back is the same, at two arm lengths, even though the straight arm pull travels a longer circular path the component perpendicular to the direction of travel doesn't provide forward propulsion. It seems to me that any advantage in a longer lever has to come from different timing. Either that or the greater downward force in the front quadrant lifts the body enough to reduce drag, and I'm dubious about that. Another explanation might be that for some reason the straight arm swimmer is able to generate higher forces at the shoulder than the EVF swimmer. I'm not sure why that would be but it seems plausible. My intuition still tells me that the straight arm swimmer is benefiting from a difference in timing, possibly spending less time in the non propulsive front quadrant. Isn't it generally the case that swimmers with a non-EVF pull have a higher stroke rate? I think you are overlooking the most important point. The reason power is greater in the deep drop elbow is that the shoulder is in the positive angle (flexion) while to get into extreme EVF, when the recovering arm is extended, requires that both shoulders are extended. Once the shoulder is extended (negative angle) it loses power mechanically. I believe one can get stronger in the EVF position with work, but it is not the position of naturally greatest strength of the arm/shoulder/ back. Gary

RE: Swim Myth #4......Busted!

jim thornton — Tue, 03 Aug 2010 10:28:15 GMT

RE: Swim Myth #4......Busted!

Former Member — Mon, 02 Aug 2010 15:00:12 GMT

What exactly is a conventional stroke vs. EVF or a non-conventional? That is a very good question. I can only answer for me at this time. For me, I feel I am swimming full blown EVF when: 1. I am achieving the steepest vertical forearm position possible as early into the pulling path as possible 2. That includes delaying the catch a tiny bit to achieve this flatter body position. The clip you once referred to a few months back is explaining this principle (which was new to me) very well as opposed to 1. going deeper and earlier on my catch which occurs with less vertical forearm position 2. Using the downward body rotation to strengthen the catch ** ** this is a key difference here for me. Under conventional free style technique, I roll down (downward body rotation) on my catch. At higher speed, I even lock the arm, similar to what Rtodd described some place else in the forum. Whereas with EVF, I kind of loose it. Catch is being slightly delayed, the arm remains shallow, downward body rotation is occurring with the arm remaining in the front quadrant. So everything is kind of late timing wise compared to my more conventional way of swimming the Free. So far, it is causing me a little issue in passing the elbow underneath the body to prepare for push phase. Working on it though...

RE: Swim Myth #4......Busted!

Former Member — Mon, 02 Aug 2010 09:36:35 GMT

i did not read every single reply but i am hoping that someone mentioned that EVF means your hand is pulling straight back towards the feet as opposed to down/back with a straight arm

RE: Swim Myth #4......Busted!

Former Member — Mon, 02 Aug 2010 09:22:45 GMT

Power is workXdistance/time(if I remember correctly).Since the lever arm is longer the hand moves farther faster.This is really an inelegant statement and since we are applying force to a fluid all simple equations are inadequate.It seems that the deep elbow causes faster peak forward velocities at points in the stroke,but with the peak being of less duration/stroke than with what I think of as EVF. The part that has me confused is that the longer the lever the larger the force at the shoulder has to be to generate the same force at the hand. If you hold force at the shoulder constant then the amount of propulsive force drops as the lever gets longer. The distance parallel to the direction of travel from the front of the stroke to the back is the same, at two arm lengths, even though the straight arm pull travels a longer circular path the component perpendicular to the direction of travel doesn't provide forward propulsion. It seems to me that any advantage in a longer lever has to come from different timing. Either that or the greater downward force in the front quadrant lifts the body enough to reduce drag, and I'm dubious about that. Another explanation might be that for some reason the straight arm swimmer is able to generate higher forces at the shoulder than the EVF swimmer. I'm not sure why that would be but it seems plausible. My intuition still tells me that the straight arm swimmer is benefiting from a difference in timing, possibly spending less time in the non propulsive front quadrant. Isn't it generally the case that swimmers with a non-EVF pull have a higher stroke rate?

RE: Swim Myth #4......Busted!

Former Member — Mon, 02 Aug 2010 08:31:25 GMT

RE: Swim Myth #4......Busted!

Former Member — Mon, 02 Aug 2010 07:25:07 GMT

Longer lever arm. Doesn't a longer lever arm translate to a smaller force at the hand for a given amount of force at the shoulder?

RE: Swim Myth #4......Busted!

Allen Stark — Mon, 02 Aug 2010 03:41:47 GMT

Doesn't a longer lever arm translate to a smaller force at the hand for a given amount of force at the shoulder? Power is workXdistance/time(if I remember correctly).Since the lever arm is longer the hand moves farther faster.This is really an inelegant statement and since we are applying force to a fluid all simple equations are inadequate.It seems that the deep elbow causes faster peak forward velocities at points in the stroke,but with the peak being of less duration/stroke than with what I think of as EVF.

RE: Swim Myth #4......Busted!

Allen Stark — Mon, 02 Aug 2010 01:46:06 GMT

Do you have an explanation for why a deep pull would generate more force? Longer lever arm.

RE: Swim Myth #4......Busted!

Former Member — Sun, 01 Aug 2010 13:16:09 GMT

Do you have an explanation for why a deep pull would generate more force?

RE: Swim Myth #4......Busted!

Former Member — Sun, 01 Aug 2010 13:09:38 GMT

What exactly is a conventional stroke vs. EVF or a non-conventional?

RE: Swim Myth #4......Busted!

Former Member — Sun, 01 Aug 2010 08:22:31 GMT

2 me 2.

RE: Swim Myth #4......Busted!

__steve__ — Sat, 31 Jul 2010 11:41:49 GMT

rocket alchemetiscience

RE: Swim Myth #4......Busted!

rtodd — Sat, 31 Jul 2010 10:25:06 GMT

I found these clips of Klim and Popov. They have contrasting strokes. To me it looks like Popov gets into EVF sooner and does not let his hands and elbows drop quite as much as Klim. The second klip shows they were both exactly 38 strokes coming home, so they were both similar in speed and stroke count but with different recoveries and pulls. Why did Popov win? I've heard it said that he maintained his speed and this results in less integrated drag. The body does not pulse forward and backward resulting in parasitic drag. If this fractional slowing and accelerating occurs 38 times over a length, it accumulates. I think EVF is important, but how you integrate EVF is tricky so you don't have dead spots slowing you down and then needing to reaccelerate. YouTube- Popov vs Klim 50m Perth 1998 YouTube- 1998 | Michael Klim Vs Alex Popov | 1998 World Champs | Mens 100 Freestyle

RE: Swim Myth #4......Busted!

Chris Stevenson — Sat, 31 Jul 2010 05:06:52 GMT

To continue to:dedhorse: I still question your more frontal drag in the deeper pull paradigm.After doing several experiments on myself to grossly measure the drag forces on my arms in a very crude way I have come to the conclusion that it is possible that the upper arm has some anti-propulsive drag,but that this is minimal compared to the rest of the body's form drag.I hypothesize that this is because the upper arm is actually moving very little in the water whereas the body is moving a great deal.I believe Rtodd is right that the smoother application of force is a big advantage of EVF .The deeper pull may generate more force at times and so benefit some sprinters where force may trump efficiency,but past a sprint traditional EVF will be better for most. This makes a lot of sense to me.

RE: Swim Myth #4......Busted!

Allen Stark — Sat, 31 Jul 2010 01:21:20 GMT

EVF can be and is used by great swimmers with or without high stroke rate. Hackett for example uses extremely high EVF with relatively low stroke rate (hip driven freestyle). Cielo uses extremely high elbow with fast stroke rate (shoulder driven). The deeper arm pull has greater power but more frontal drag. The EVF position and high elbow sweep has lower power and less frontal drag. The ideal position is hard to determine because it may depend on each swimmers ability to generate power in the EVF position (requiring extreme ability to extend the shoulder joint). Does EVF lead to greater vulnerability to shoulder injury? A good and interesting question. I do not know the answer. Gary To continue to:dedhorse: I still question your more frontal drag in the deeper pull paradigm.After doing several experiments on myself to grossly measure the drag forces on my arms in a very crude way I have come to the conclusion that it is possible that the upper arm has some anti-propulsive drag,but that this is minimal compared to the rest of the body's form drag.I hypothesize that this is because the upper arm is actually moving very little in the water whereas the body is moving a great deal.I believe Rtodd is right that the smoother application of force is a big advantage of EVF .The deeper pull may generate more force at times and so benefit some sprinters where force may trump efficiency,but past a sprint traditional EVF will be better for most.

RE: Swim Myth #4......Busted!

Former Member — Fri, 30 Jul 2010 13:07:26 GMT

I echo SolarEnergy's question. Swimming speed (m/s) is determined solely by DPS (m/stroke) and stroke rate (stroke/s). The trade-off between the two is apparent in comparing people like Phelps and Sullivan. If the effect of EVF on DPS are neutral, then for it to be clearly superior to "conventional" freestyle it must be that adopting EVF increases stroke rate. Is that the case? Or is it just that successfully adopting EVF is indicated by an improvement in DPS? EVF can be and is used by great swimmers with or without high stroke rate. Hackett for example uses extremely high EVF with relatively low stroke rate (hip driven freestyle). Cielo uses extremely high elbow with fast stroke rate (shoulder driven). The deeper arm pull has greater power but more frontal drag. The EVF position and high elbow sweep has lower power and less frontal drag. The ideal position is hard to determine because it may depend on each swimmers ability to generate power in the EVF position (requiring extreme ability to extend the shoulder joint). Does EVF lead to greater vulnerability to shoulder injury? A good and interesting question. I do not know the answer. Gary

RE: Swim Myth #4......Busted!

Former Member — Wed, 28 Jul 2010 15:11:50 GMT

I have improved the distance per stroke quite considerably so far when adding a lot of EVF to the stroke. I detected an issue with the non breathing side arm, which I am improving by focusing on 1-Arm drill, breathing on the non stroking arm. I am also working on something little more difficult to solve: the passing of the elbow. This transition during which the elbow passes underneath the body to allow for optimal push. I find it more difficult to preform this passing of the elbow when adding more EVF than usual. This may in part explain why some swimmers could generate more torque in the FQ compared to the BQ. In my case, this passing seems to occur too late for being able to use upward body rotation to support the last third of effective pulling range. But getting there though... and it feels pretty natural too, at least the front quadrant portion most definitely. Should be able to post footage including UW ones soon.