In looking at the animation on www.swimsmooth.com I see that the hand follows a straight path front to back. This is probably better seen when looking up at the swimmer from under water. If you put a ruler to the path it is pretty much a straight line.
Now, I've seen and I've read posts that talk about a non-linear path. I guess the idea is to always try to accelerate new water rather than applying force to water that you've already accelerated.
So...why do they show a straight path.
And, if curved is better, what is the best path?
Parents
Former Member
While the notion that pulling in the exact opposite direction from the line of progress makes perfect sense, as in paddling a canoe, the biomechanics of the freestyle armpull makes the story a bit more complicated.
Here is some of what I (currently) believe:
The arm should extend on a straight line between the shoulder joint and the point at which you intend to contact the opposing pool wall.
The armpull should begin with a tilt of the wrist and forearm, cocking somewhat at the elbow, to make the lower arm a full paddle as soon as possible in the pulling movement. EVF.
In order to maintain the largest bent-arm paddle, the arm will rotate towards a more horizontal pull, and the hand will traverse toward the body centerline, as it passes under the thorax. The upper arm is now also a part of the paddle.
As the arm passes under the abdomen, it begins to straighten and curves outward again to the body's side.
Handspeed should steadily increase throughout the movement, especially as the arm exits the water, to minimize eddying. The same principle applies in canoeing, where the paddle should accelerate through its pull and exit the water in a fast, slippery, eddy-free lift.
The arm that pulls while a breath is being taken will naturally traverse toward the body centerline more than the other side armpull, because the body rotates (logrolls) more on the breathing side.
One question is why the armpulls for the breaststroke and butterfly shouldn't follow the same general principles, with modifications for the different stroke mechanics. A sideward outsweep at the beginning of the armpull is the conventional wisdom that is particularly questionable. Why wouldn't the beginning of the *** and fly armpulls be highly similar to the freestyle movement? If so, here goes:
In butterfly, the hands begin at least at shoulder width, use the entire arm as soon as possible in the movement, traverse steadily toward the body's centerline during the movement, finishing and exiting quickly to minimize eddying.
In breaststroke, the hands move apart after streamlining, then begin a bent-arm pull that has a slight rotary arc, so that the insweep-to-recovery phase can happen with maximum handspeed, leaving the eddies behind and well below the body.
Who really knows. You never see any of the creatures at the aquarium using anything like a canoe paddle, and they get around just fine.
While the notion that pulling in the exact opposite direction from the line of progress makes perfect sense, as in paddling a canoe, the biomechanics of the freestyle armpull makes the story a bit more complicated.
Here is some of what I (currently) believe:
The arm should extend on a straight line between the shoulder joint and the point at which you intend to contact the opposing pool wall.
The armpull should begin with a tilt of the wrist and forearm, cocking somewhat at the elbow, to make the lower arm a full paddle as soon as possible in the pulling movement. EVF.
In order to maintain the largest bent-arm paddle, the arm will rotate towards a more horizontal pull, and the hand will traverse toward the body centerline, as it passes under the thorax. The upper arm is now also a part of the paddle.
As the arm passes under the abdomen, it begins to straighten and curves outward again to the body's side.
Handspeed should steadily increase throughout the movement, especially as the arm exits the water, to minimize eddying. The same principle applies in canoeing, where the paddle should accelerate through its pull and exit the water in a fast, slippery, eddy-free lift.
The arm that pulls while a breath is being taken will naturally traverse toward the body centerline more than the other side armpull, because the body rotates (logrolls) more on the breathing side.
One question is why the armpulls for the breaststroke and butterfly shouldn't follow the same general principles, with modifications for the different stroke mechanics. A sideward outsweep at the beginning of the armpull is the conventional wisdom that is particularly questionable. Why wouldn't the beginning of the *** and fly armpulls be highly similar to the freestyle movement? If so, here goes:
In butterfly, the hands begin at least at shoulder width, use the entire arm as soon as possible in the movement, traverse steadily toward the body's centerline during the movement, finishing and exiting quickly to minimize eddying.
In breaststroke, the hands move apart after streamlining, then begin a bent-arm pull that has a slight rotary arc, so that the insweep-to-recovery phase can happen with maximum handspeed, leaving the eddies behind and well below the body.
Who really knows. You never see any of the creatures at the aquarium using anything like a canoe paddle, and they get around just fine.
