DO WE NEED TO PUSH IN RUNNING (SPRINTING)?
As I mentioned in the previous parts of this topic, the question about push off is a very interesting thing for me, very challenging and exciting. I was taught, as everybody else involved in training and racing in track and field, that push off is the cornerstone of technique and the most efficient way to best results in running. So I did perform millions of "special" exercises to develop my ability to do push off. I became very good in performing these drills, but my running abilities didn't improve too much. On the opposite, the better I got with exercise performance, the weaker and more hopeless I felt in running. I was puzzled with this conflicting results of my training.
A bit later, I was still in the same field, but being already a coach and scientist myself I started analyzing this controversy. In the middle of 70-ies sport science began accumulating facts conflicting with the existing push off paradigm. By the end of the 20th century these facts already became undeniable, but they still did fit into the dominating concept. Running science and coaching communities were sticking to the old mindset that our muscles are the main reason why we could run fast. Or how Sir John Lubbock said: " What we see depends mainly on what we look for".
So for what difference from the old paradigm we are looking for? We think, and we have a reason to think this way, that the major motive force for running forward is gravity and our muscle efforts are just assisting and reflecting the work of this divine force.
Let's just look at one single example from the 60-ies. In the picture we can see the gold medal winner from 1964 Olympic Games in Tokyo, Japan, the great American sprinter, Bob Hayes, running from the starting blocks. I would like to stress several points at just one single step from the blocks he is running.
|(Click on the photo to see a larger image)
Our common sense tells us that what we see are tremendous efforts to push off from the blocks. And it is very difficult to reject, if we do not have any another alternative way of thinking. Take a look at the "set" body position compared to the white starting line, then look at the consequent positions of the body until the foot from the rear block lands on the ground. The interesting fact about this position is that the foot is under the GCM (general center of mass) of the body and close to the starting line. If we compare this distance with the distance from the starting line to the GCM projection on the ground, on the previous picture, where the athlete is positioned with the fully extended leg on the front block, then we can see that these distances are the same.
What does this fact tell us? That the body is just falling from the blocks forward and muscle efforts are used to move the body up and keep it in the falling position. There is only a slight movement forward, but mostly the rear foot is placed approximately in the position where the hands were previously on the support. So the body weight is just transferred forward by falling from the blocks. Muscle efforts are needed to keep the body on support and neutralize too much available gravity force in the position where the athlete is in the blocks with his feet and hands off from the support. This body position is simply representing a complex interaction of forces in order to unleash gravity to move the body forward. And this happens at every step, but is camouflaged by the visible muscle efforts, which are used for the different purpose and are mostly recruited on the subconscious level. Their efforts should be regulated by falling and serve it, as well. This is the main logic of forces work in running which we have to understand and accept in order to make our running efficient and economical.
ILLUSTRATED GUIDE TO OLYMPIC TRACK AND FIELD TECHNIQUES
Parker Publishing Company, 1966
The Dash Start
THE ATHLETE: Bob Hayes, U.S.A.
by Eric Broom
THE AUTHOR: Eric Broom is the British National Honorary Coach of Sprinters, and is currently Professor of Physical Education at the University of British Columbia in Vancouver.
"On Your Marks." This is the bullet-type start, with the front foot approximately 20 inches from the line and the feet 10 inches to 12 inches apart. It is a position of relaxation.
"Set." Hayes shows a basically sound position. The angles at
the back of the knees are approximately 900 (front leg) and 1200
(rear leg). The back is flat, with the hips slightly higher than the shoulders. The hands rest high on the finger tips, giving maximum possible height to the shoulders; but Hayes' shoulders have a tendency to be too far ahead of his hands, thus putting too much weight on them. The neck is relaxed, and the head is in natural alignment with the back. This is a steady position, and one which gives the impression of coiled power awaiting the stimulus of the gun.
"Gun." The first movement following the gun is a slight raising of the shoulders so that the forward drive can be transmitted in one straight line from the front foot to the head. The head, basically, is still down, but the eyes are beginning to lift.
This is a continuation of the forward drive from the front leg.
The rear foot has already left the block before the leg or ankle are fully extended, thus providing little forward drive from that leg. This is an inevitable result of a bullet start. The medium start, where the front foot is 10 to 14 inches from the line and there is approximately 14 inches between the feet, makes possible a more effective rear leg drive.
This is a further continuation of the forward drive from the
front leg. There is a further lifting of the eyes and head.
Here is a further forward drive of front leg, with the rear leg coming through. Hayes' arm action at this point is interesting. His right (rear) arm is good, with the elbow and hand high behind the body. His left (front) arm is moving in more of a lateral than a forward action. This unusual arm action, plus the tendency to drive from the front leg only in the starting position, could be the cause of the "rolling" action which is characteristic of Hayes' start.
This shows excellent front leg drive, the power being transmitted along a straight line from the foot to the head. The left arm is moving in a lateral rather than an upward plane.
The middle of the first stride.
The supporting phase of the first stride, with front (left) leg
The end of the supporting phase.
Hayes shows excellent drive extension, right on through the toes. The rear (left) arm is good with the hand beyond the hip and the elbow high. The right arm appears to be moving on a lateral plane.
The supporting phase of the second stride.
|(Click on the photo to see a larger image)