Myth #4: The reason you keep the elbows high on the underwater pull is to increase power.
I hear this often from both coaches and swimmers. When one looks at the underwater shots of the world's fastest swimmers, sprint or distance, one finds the recurring position of high underwater elbow, also called Early Vertical Forearm (EVF). The elbows are not just high, they are unusually high...almost in a contorted position with extreme extension (negative angle) of the shoulder joint, particularly when coupled with the body rotation in the opposite direction. it begs the question, can one really be stronger in this almost contorted position? I believe the answer is no. To test this, one can go in the gym and using the Free Motion pulleys, that many gyms now have, pull as much weight down with your arm relatively straight forward, then try it with your arm at the side, shoulder extended and elbow up. You will not be able to pull as much weight in that position. With the shoulder fully extended (negative angle), it is simply not in a good mechanical position of strength.
So if this weird high elbow position is not about power, what is it about? Drag. By changing the position of the arm as it moves through the pull cycle, one can reduce the drag coefficient significantly...not eliminate it. To prove this, kick with fins all out for 25 yards extending one arm above the head and the other straight down toward the bottom of the pool. You will soon learn how significant the drag of your protruding arm becomes when it is at right angles to your long axis. In fact, you will have to work to keep the arm in the position and with any speed at all, it will shake in the water like a palm tree in a hurricane in the Keys. Now try the same drill, but instead of putting your arm straight down, let it protrude straight out to the side but bend the arm 90 degrees at the elbow, as if you were swimming with a high elbow. You will feel considerably less drag in this position. Same arm...different position...a lot less drag.
Now I realize that this is not quite the same as while swimming, when only the upper part of the arm is moving forward throughout nearly the entire underwater part of the pull cycle (In order to cause frontal resistive drag, the object must be moving forward). However, the upper arm is also the largest part of the arm and changing it's orientation in the water also reduces the drag coefficient. Achieving an EVF is simply maintaining the upper arm in a position closest to the line of motion and thus creates the least frontal drag.
The good news is that most coaches are telling you the same thing, pull with your elbows high underwater. Now you know the real reason.
Gary Sr
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.
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
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.
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.
Regardless of what is providing the resistance to movement, (water VS weight, springs, etc.), the total power expended by swimming is simply the total Force X Distance / Time. However since your arms and legs are submerged, the radius of the parts that are moving through the water (and their resistance) are also a factor.
Therefore the equation for determining the total power expended in swimming involves integration (a calculus process) rather than simple algebra. If there are any math whizzes out there, they can give you a qualitiative answer for what ever it's worth.
D2
