Monday, December 2, 2013

The Jerk - David Webster
















In describing the pull for snatching and cleaning we began with the grip on the bar,
and we must do the same for the jerk.

Although the hook grip is advised during the pull it is certainly not advised for a jerk. It would actually be a disadvantage, so he hook must be released. Many lifters actually release the hook during the recovery from the clean, a time when the wrists are often very much extended; the weight may even come on to the fingertips. I know several lifters whose little fingers come off the bar. These lifters would be well advised to note my comments about getting the weight into a good jerking position as they thrust upwards at the final part of the recovery.

However, it is also true to say that many champion lifters actually adjust their grip round the bar during the early part of the jerk. The noted Plyukfelder (USSR) was quite astonishing to watch as he would completely re-grip the bar at this stage; he would also mess about in training by actually taking the dip with one hand spacing and during the jerk would widen this hand spacing considerably! This was just one of Rudy Plyukfelder's many lifting idiosyncrasies - a most interesting lifter. The one thing I would stress about the grip prior to jerking is that there is no need to grip the bar hard - a very loose grasp is quite acceptable and preferable to setting up tensions which have a cumulative effect on other factors involved in the lift.

While lifters must not hold the weight at the shoulders for a long time, it is important that they settle the bar and themselves correctly. The calming effect is a necessary part of the lift and research has shown that a hurried jerk, not pausing sufficiently at the shoulders, was a significant source of failures in the lift. The pause must be long enough for the lifter to be comfortably positioned, poised and composed for a maximum, controlled effort. It should be no longer than this, for waiting too long before jerking is just as bad (although not as common) as being too hurried.

The same principles for the snatch and the clean are applied but in a different way. The feet should be parallel with each other and placed hip width apart. The knee bend (dip for the jerk) is the movement used so that the big strong muscles around the center of gravity can be brought into play. These are used first and the shoulders, arms and calves are used later in the thrust. Some lifters use too much arm strength too soon in the belief that it gives better direction and control. You can generally identify these lifters by their low elbow positions. We can learn a lot from a review of outdated styles and I would point to the fact that even in the now defunct press, arm power became less important than the thrust from the hips and back (and even loosely locked legs!). The fast pressers had their elbows well forward. One other point to consider - too early and too much arm action will upset the timing of the lift. Keep to the policy of using big strong muscles first and the small weaker ones later.

In the dip for the jerk direction is all important. Aim at going directly down and directly back up with the minimum of bar displacement. The feet should be kept flat on the floor during this dip. There has been only one exception to this rule - Huska of Hungary - among all the world champions I have studied.

The necessary dip is often underestimated and a number of good lifters would profit by a bigger and speedier dip and thrust. One of the most significant pieces of lifting research from the Orient shows that a significant number of jerks fail not so much because of lack of strength on the part of the lifter, but because of failings in technique, e.g., insufficient knee bend in the dip.

The researcher Chu Tse-Chiao stated that the two main causes of failure were starting the jerk too early and not enough knee bend in the dip (although there are of course other very common reasons for failure at a later stage of the lift). Chu Tse-Chiao suggested that the knees be bent to 110 to 115 degrees; British researchers, looking at general athletic performance rather than at weightlifting specifically, have found that 115 degrees between calves and thighs allows the most vigorous extension of the thigh.

My own measurements and observations show that the champions bend to a maximum of 110 degrees and the least bend is around 120 degrees. These independent investigations support the recommendation of 110 to 115 degrees bend.

There is a lot of misunderstanding concerning the thrust prior to the jerk. Just as in the pull, force must be applied over as long a distance as possible but what is not normally given much thought is that without a decent dip the thrust would be a very short one indeed. Let me elaborate.

In a good thrust, about 60% would be as a result of the dip and the remaining 40% - before the feet leave the ground - would be the difference between normal standing height and the full extension caused by rising on the toes prior to the split.

It would be detrimental to alter these proportions by (a) reducing the depth of dip or (b) increasing the thrust by using more arm strength prior to the split. The soundest technique is to split as a flowing continuation of the thrust, with the feet moving as soon as the legs can no longer add further momentum to the bar.

A remarkable number of otherwise knowledgeable lifters have no idea how short the thrust really is. In the majority of cases, and I am referring to champions, the split begins when the thrust has just lifted the bar off the chest and is no more than throat or chin level. This will be a revelation to most lifters, I am certain.

Once again speed is all important. In the very short time between the feet leaving the ground - when the bar is no higher than chin level - and the time that the feet land the arms must almost straighten. A very strong arm movement is, of course, essential and this has a two-way effect. It helps to get the body under the bar and transfers momentum to the bar as soon as the feet land.

In splitting, the feet should always leave the ground at precisely the same instant whether in the snatch, the clean or the jerk, but unfortunately it is very seldom this happens. Instead, lifters nearly always anticipate the split and before the extension is concluded they automatically begin transferring their weight (on to what becomes the forward foot) so that they can easily take away the foot which goes backwards. This has a very detrimental effect. Firstly, it robs the lifter of a two-legged thrust. Secondly, it gives one leg more work than the other and thirdly, it upsets balance because the barbell also begins to move to one side as the weight is transferred. This fault is very common indeed and some lifters anticipate so much that even in the dip they begin shifting their body weight on to one leg.


When split snatching was in vogue, 'pulling on one leg' was the most common fault of all. When you see a lifter stagger sideways with a weight, take note of the direction in which he initially staggers. Almost always it well be to the same side as his forward leg. This is because the weight will have started in this direction when there was a transfer of weight prior to splitting. The correction of the fault lies in concentration on a good dip with weight equally balanced on both feet (your coach or training mate should watch from the rear and will easily spot any favoring or one leg) and a good drive with both legs before the feet leave the floor. It is almost impossible to get both feet moving off the ground at exactly the same time and the experiments I have done on force plates show that it is in any case not absolutely crucial that they do. I often found that although the back foot moved faster and further, the front foot was virtually unweighted at the same time so there was no loss of balance with the best lifters. IF the re is any sign of poor balance check on this point at once. If one end of the bar is lower than the other during the jerk or one arm appears to straighten first check again for weight transference as these are symptoms of this fault.


        
Arm Action in the Jerk

Recapping on the starting position for the jerk - the elbows should be raised so that the weight is carried not by the arms but by the shoulders. the drive from the legs is transmitted to the bar and the weight will rise to around throat or chin height before the feet leave the ground. The dynamic thrust will  carry the bar upwards so that as the feet land the arms will almost be straight. The slight bending of the legs will 'cushion' the heavy weight and will lower the body enough to allow the arms to straighten. However, the legs must be firm enough to give a good base for for the very strong arm action which must be used at the conclusion of the jerk. It should go without saying that maximum arm strength is used in conjunction with the other muscle groups. 

The lifter must avoid three things which will make arm action very difficult in the final lockout:

1) bringing the biceps into play too soon or other movements which put the bar out in front

2) moving back from the weight so that the shoulders are behind the hands at the time of the completion of the jerk, and

3) failing to follow through vigorously, getting shoulders and head under the bar at the end of the jerk.

Let us look at these points in more detail.

I teach what I have termed the 'open' jerk, for in this the elbows are consciously opened as the lift is performed. It is not unnatural for the elbows to move from their forward position into their final overhead position in a direct straight line. However, I prefer to whip the elbows sideways as soon as the bar is in flight so that they are under the bar as quickly as possible. In the former method they are not under the bar until the arms are finally locked and this is not only mechanically less efficient, there is always the tendency for the shoulders to keep back when this style is used.

The next factor spotlights  another of the most common faults when there are failures in the jerk. How many times do you see a lifter get the weight to arms' length or nearly to arms' length overhead, and simply fail to hold it? It is a common sight and while failing with a weight that is too heavy for the lifter is excusable, there is no excuse whatsoever for many of the failures - they are due to poor technique. Yet I have heard lifters in such circumstances ask for advice and be given wrong information. 'You put the bar out in front' is the normal explanation given and while this is sometimes the case, I have seen many instances when the bar was in the right place and the lifter was too far back from the bar - which is entirely different.

 

Two positions are illustrated:

a) When the lifter has straightened the arms but is still behind the weight; and

b) the more common landing position, when the feet hit the floor and the arms are still slightly bent.

In both cases there must be a decided effort to get the head and shoulders under the bar in time with a slight sinking of the body, by thrusting the front knee forward. All too often there is the sink without the head and shoulder action. A very positive attitude is required in this movement and if you can master this combination, then success in jerking will be yours.

On a coaching note, you can always tell if a lifter has put the bar forward or the lifter has stayed behind the bar, by comparing the starting and finishing positions of the bar. The observant coach will always locate the bar position in relation to static objects in the background. It becomes second nature after a time and it is a practice worth cultivating, for body position alone tells only part of the story.



The Path of the Bar in Jerking

The dip brings the bar very slightly forward as the knees and hips are flexed. The jerk proper puts the bar on an almost vertical path. At the end of the lift there is a slight movement backwards. If there is undue movement backwards (amounting to more than 3 to 4 inches) the lift is likely to be lost. The more vertical the path of movement in the jerk, the better the lift. In recovering from the split, once again the frint foot is moved back slightly and the rear foot is brought up into line. Be meticulous in this as even champions have been disqualified for their feet being out of position; there is the classic case of John Bolton of New Zealand who lost a Gold Medal at the Commonwealth Games because of this fault.

These then are the basic techniques of the snatch and the clean and the jerk. Although there is more written here than in almost all other books on the classic lifts, I assure you I have only scratched the surface and there is a great deal more to learn, particularly on the theoretical side, so that you can understand the cause and effects of various movements and idiosyncrasies. The more knowledge you acquire the better will be your lifting, your coaching, and your appreciation and enjoyment of lifting.


NEXT: LEARNING SEQUENCES FOR THE LIFTS    













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