Monday, November 14, 2011
The Development of the Clean & Jerk, Part Three - David Webster
Column 1 - Starting angle of the back, measured in degrees from the horizontal.
Column 2 - Angle of the back as the bar passes the knees.
Column 3 - Line of thrust from hips to center of back.
Column 4 - Extension line. Neck to center of base.
The Development of the Clean & Jerk, Part Three
by David Webster
Let me explain next why the upright start is so poor.
If the back is kept very upright the lift depends almost solely on leg strength and very good poundages are not possible if the hips and back do not do their full share of the work. Therefore the “upright stylists” having started in this way, tend to bend forward during the lift in order that the back and hip muscles may be brought into play later. Not only does this result in a negative unnecessary forward and downward action, it reduces angular momentum. Although the legs are straightening, the back is bending so the bar rises LESS than it would and SLOWER than it would if the back angle were maintained.
Even with a more orthodox starting position this back angle is hard to maintain (as you will see by Table 1) and this is why it is so necessary to pull steadily from the floor instead of putting everything into the initial pull.
IF you pulled as hard as possible from the floor you would find that, because of the difficulty in overcoming inertia, your hips will have risen high and your shoulders have risen hardly at all.
“STEADY FROM THE FLOOR” MUST BE THE RULE, AND TRY TO MAINTAIN OR EVEN SLIGHTLY INCREASE THE ANGLE OF THE BACK. By this I mean you should keep the back set at the same angle or make it a little steeper.
In the starting position I recommend that in the average man, the vast majority of lifters not being of freakish proportions, the back should be at an angle of between 25 and 35 degrees. I am definitely against the back being at an angle of over 38 to 40 degrees for the reasons given.
The second illustration of Jimmy Moir and the photograph of Kurentsov (see Part Two) show angles of which we approve.
When The Bar is Passing the Knees
Having pointed out the fact that the angle of the back must be maintained during the first part of the lift, it should be pointed out that just as it is a fault for the back to become less steep it is also wrong for it to become too steep. If the back has become much nearer to the vertical than it was in the starting position, a number of faults are likely to occur. If this happens with squat lifters they will likely jump backward, and with splitters they are almost certain to transfer their weight onto the forward foot, and splitters, too, will tend to jump backward. As has been pointed out in another section, the cure for these faults is to keep the shoulder further forward than the bar until the bar is well past the knees, and make sure that the hip thrust is used to extend the body rather than heaving the shoulders backward. If you look at a still photo or a cine frame, when the bar is passing the knees the back should be at an angle which is just a LITTLE steeper than it was in the starting position, and personally I would not worry at all if the lifter was still at the same angle as he was at the start, as I know there is almost bound to be some decrease in the angle and then it corrects itself , in the good lifter, as the bar reaches approximately knee height. It is from knee height upward that you must try to build up maximum speed of back movement and try to move the back through a wide arc, but you must move the hips forward and upward at the same time.
Often when the plates are on the floor the bar is not over the center of the instep, but nearer to the toes. I, personally, can get it nearer to the instep than the toes without having my shin bones too vertical, and prefer it that way. If, however, it is nearer to the front of your feet as the plates clear the platform, you must pull the bar closer to the shins so that it is over the center of your base (i.e., the feet). The nearer the weight is over the center of the base, the more stable the position. The fact that the knees move backward slightly will permit the bar to pass without touching. Cine tracings of the bar path of movement show that the bar comes back slightly as it passes the knees. Please do not consider this an S pull. I define an S pull as one where the natural slight curves in the path of movement have been exaggerated. This will be dealt with in more detail in another part of this book.
If we could get someone with the power and technique to get the hip line of thrust to around 90 degrees and the extension line to 103-104 degrees we would get some sensational lifting. The AIM (which would not be possible with top weights) should be a position similar to Figure 12 (Pearman). By aiming at this, a good hip and extension line may be achieved. The hip thrust must be forward and UPWARD.
Measurements of angles were taken from as near as possible to the 5th cervical vertebrae to the flat part of the sacrum just above the curve of the lifter’s buttocks. Back contours were ignored; if a lifter lifted with a round back the line passed through the curve. See Figure 13.
Caution!
A complete and true picture CANNOT be built up from statistics alone. The measurements given are aids to analyzing and to allow a comparison between the top lifters and lesser lights.
These statistics have a useful part to play bur measurements alone could be very deceptive. For example the head is comparatively light and the neck muscles would appear to play a very minor role in a Clean & Jerk. Yet the action of the head can play a major role in dictating the lift. Because of its position at the enc of the spine it acts as a “rudder” to the body. The results of poking head technique at the end of an overhead lift are now quite well know and there are other obvious reactions. DYNAMICS AND ACTUAL MOVEMENTS MUST BE CONSIDERED, NOT MERELY STATIC ACTIONS.
A further point which cannot be left out is MENTAL REACTION and in the Clean there is a classic example. We have outlined the positions which will give a good, balanced Clean and it is a well known fact that one of the most common faults in the pull is allowing the shoulders to come back too early, thus bringing the combined center of gravity backward over the heels. The MECHANICAL reaction to this action has been explained, but if the man is a splitter there is another almost automatic reaction without physical mechanics. The lifter, knowing that his weight is traveling backwards, without even thinking about it, will wish to re-establish his balance. He will then prematurely move his rear foot. This results in a loss of power, and instead of re-establishing balance will only delay loss of balance as he will then tend to lose balance SIDEWAYS. The correct thing to do is to improve the pull not to adjust the split. The point to be emphasized, however, is that the premature split is not a mechanical one but a mental one. Statistics and measurements can’t reveal things like this, but they do have their part to play.
Balance in the Clean & Jerk
The above theories lead us on naturally to discuss balance in the Clean & Jerk. Weight transference comes under this heading, but as it was covered separately we will deal only with balance in the split and squat.
The fantastic adjustments a lifter has to make in timing and balance are appreciated by very few. Balance is dependent amongst other things on center of gravity of the lifter and also the bar. Have you ever stopped to think of the different speeds and paths of movement of these two centers? In the Clean, the personal center of gravity goes higher than the bar in the pull, but must drop lower at the completion of the movement to get under the bar center of gravity. A complicated move to say the least. Very fine adjustments are made as teh weight increases, for if you start going down too soon you’ll lose power and if you leave it too late you won’t have time to lower the personal center of gravity and the bar will probably drop down in front of you. You must also avoid being pulled into a folded up position. Balance and timing are of major importance.
The main factors involved in balance are
(a) The height of the combined center of gravity of the lifter and the bar.
(b) The size of your base.
(c) The horizontal distance from the center of gravity to the pivoting edge of the base also affects balance, as does,
(d) The total weight of the combined objects.
The first factor, height of the center of gravity, is easy to understand. The lower the combined center of gravity the more stable the position, so it’s easy to see that once again low positions under the weight are advantageous. It is also clear that the squat is better in this respect. What about the size of the base? The larger your base the more stable the position and, contrary to popular belief, the base for the squat is generally larger than the base for the split. This comment may be challenged but a glance at the illustration will prove my point. These are for an average lifter of 5’8” in height. The only factor which favors split lifters is the third one and even here there are vital differences.
The drawings show how the squatter has more lateral stability while the splitter has better balance fore and aft. The latter gives most trouble to lifters and furthermore sideways adjustments to save lifts are possible for a splitter, but once a squatter goes down, foot movements can seldom be used to save a lift.
The other advantage of the split is that a lifter can adjust himself OVER his base quite easily. You will perhaps see that the lifter moves slightly SIDEWAYS as well as forward and downward toward his front feet. This is always evident in a good low split. Be warned however, it happens to an undesirable extent where the lifter splits too diagonally. Always try to get your feet splitting directly forward and backward rather than diagonally. This means in a straight line forward and back from their starting position. IT DOES NOT MEAN FINISHING WITH FEET ON A STRAIGHT LINE – THIS IS A BAD FAULT.
You will see that factor (c) alone favors the splitter. This style definitely permits the saving of lifts which are far from technically perfect. Apart from that, the squat is definitely superior.
One final point on stability. In terms of mechanics, there is greater stability where levers are at right angles to the fulcrums. When the lever rests obliquely there is less stability. My favorite example is the rear foot in the split position. Mekanik, the old Russian coach, discussed this with us at one of the world championships, and I recalled his words at the 1965 residential weightlifting course in Scotland when one of the lifters was suffering from ankle injuries. Providing this lifter got his rear foot position right his lifts were good. As soon as he went even slightly off the right angle with his rear foot he lost stability and lost the lift. Even without injuries “looseness” in this region will have unfortunate results in the form of lost lifts. Push the heel backward to give a firm position. The “thrust reflex” theory is an associated factor of general interest. If the foot is placed as suggested the toes of the rear foot will be spread slightly and there will be a correct triggering off of a series of reflexes. First the calf muscles will automatically be contracted and will push the body forward. The thigh extensors, with muscles of the trunk and hips all contracting, will help produce the desired effect (see Fig. 16). If, however, the foot is splayed inward as shown in Fig. 17, there will not be such a good thrust reflex.
Balance is vital to all lifters. It is so important that some special work should be done to improve these skills. I always have a roller board lying around on which I practice. I heartily recommend this sort of thing to all lifters, especially those who have any bother with their balance.
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