Factors that may influence a Weightlifters Pull Michael Conroy, Idaho Weightlifting

Transcription

1 Factors that may influence a Weightlifters Pull Michael Conroy, Idaho Weightlifting This article is a compilation of many articles, written on pulling and the factors that influence it. I have had this material for so long and have altered it so much (So I could use it when presenting) that I no longer remember, exactly, which authors should get credit for which parts. What I do want the reader to understand is that this article is, by no means, an original thought by me, but an arrangement of material based upon the basic bio-mechanical principles of weightlifting, an understanding of human somatotypes, and in reference to anthropomorphic measurements. Weightlifters and their coaches are, in general, a very educated group so the terminology that will be used in this article will be understood by the target audience. Somatotypes: There are 3 accepted models of human somatotypes. In weightlifting, however, it gets a little more complicated than just, muscley, skinny and fat. In fact one publication has listed 9 suggested somatotypes for men and 27 for women. In this article we are going to deal with these three. Type One: Arm length is greater than body height ( The Albatross ) Type Two: Arm length is equal to body height. ( Proportional ) Type Three: Arm length is less than body height. ( Mr. Stubby) The understanding of these somatotypes can, markably, effect pulling positions, which in turn, can affect barbell trajectory. If a coach is a believer that the barbell brush should be High on the Thigh in order for a lift to be successful the results can be very different for an athlete who is 5 2 tall with a 5 0 wingspan as opposed to an athlete that is 5 10 tall with a 6 2 wingspan.

2 Regardless of what somatotype your athlete has there are basic biomechanical principles that must be adhered to if an athlete is to have an opportunity to successfully complete a lift. Basic Biomechanical Principles Governing Weightlifting Technique A tremendous amount of research has been devoted to finding out just, exactly, what happens to a barbell when an athlete attempts to move it from the platform. The result of all these studies is that definite movements occur when a lift is successful. Starting Position The starting position, for a weightlifter, is of primary importance. An athlete cannot finish right if they start wrong. 1. All body levers are tight. USAW Coach Bob Takano has a great comment. If you are comfortable, you re probably doing it wrong. 2. The back should be flat and even have a slight, concave, curve to it. 3. Arms straight. Elbows locked and rotated outwards. 4. Head is up 5. Hips higher than knees (Suggestion) 6. Shoulders in advanced of the bar. (Suggestion) 7. Feet in the athletes vertical jump position. (Suggestion) (A lot of research has been compiled on just where the athlete s feet should be positioned and in which direction they may need to point. The research seems to suggest that a good starting point would be that the feet should be placed under the barbell at the metatarsal-phalange joint (where the toes meet the foot ) and slightly turned out. Adjustments to how much closer to the barbell or further away from the barbell the athlete should be (as well as how far out the feet should be turned) will be determined by how the stance influences the barbell trajectory. Having the barbell move back over the foot immediately as it leaves the platform) The first item that the coach should look at is the lateral distance between the athlete s buttocks and their nose. This position is now the original Center Of Gravity (COG). The Area of Base of the lifter is the position of the feet, for the pull. The line of action is the path the barbell takes during the pull. Stability of the lift is based upon keeping the barbell within the line of action and the base of the lifter the feet, during the execution of the pull. If the athlete allows the barbell to move outside of the COG, during the pull, success is unlikely. The Pull Pulling the barbell from the floor, in either the snatch or the clean, has become an exact science.

3 The barbell s inertia is the first thing the lifter must overcome and to do this, efficiently, the coach must be conscious of the force sources available and the order in which they should be used. 1. The barbell must move back towards the athlete, immediately. 2. Hips and shoulders rise at the same rate. 3. Head stays in a level position. 4. The 2 nd Pull must be faster than the 1 st Pull. 5. The athlete tries to stay flatfooted as long as possible 6. The arms only bend to pull the athlete under the barbell. 7. The feet move from the pulling position to the receiving position. Special Note: The 1 st Pull is the pull from the floor to a position just above the lifter s knee. The 2 nd Pull is from the above the knee position to a position of full extension. (Sometimes referred to as the top of the pull ) When the 2 nd pull is faster than the 1 st pull the barbell has very little time to move laterally and therefore moves vertically. Research has shown that when the 2 nd Pull is faster than the 1 st Pull chances of a successful lift increase substantially. Receiving Positions As the athlete extends the body to finish the pull The COG rises. In order to compensate for this the feet must re-establish a new Area of Base, while keeping the line of action within it. The athlete should jump their feet into a position that is approximately a shoe width wider than the pulling position. You will notice that in the above statements that I have stated some starting points as suggestions. This is because these critical positions are greatly influenced by the athlete s somatotype and anthropomorphic measurements, (Limbs and their relationships to one another) ever wonder why? our sport is participated in by so few, in the U.S.? It is because little changes can have monumental consequences and both coach and athlete must be dedicated and committed to finding just what these little changes need to be. TWO TYPES OF PULLS WE DON T WANT While we can agree to disagree on a lot of the information in this article I am confident that we can agree to agree that there are pulling styles that are just not effective. Two that come to mind are the infamous rounded back pull and the, unfortunately, all too common Human Pez Dispenser pull. (You could possibly insert the bent arm pull as a third pull we don t want, but since you see so very few efficient competitive lifters who do not pull with a straight

4 arm I am hopeful that we, in the sport, have agreed that the straight arm pull, as listed above, is the most efficient way to use the arms.) As can be seen in this line drawing, pulling with a rounded back can produce 3 bad effects. The barbell will drag and reduce the chances of the 2 nd pull being efficient. The barbell trajectory will loop around the COG and pull the athlete forward which may result in the barbell crashing on the athlete. The Pez head will result in the application of Newton s Third Law of Motion. for every action there is an opposite and equal reaction. If the athlete throws their head and shoulders backward, instead of shrugging the shoulders straight up and keeping the head still the barbell will rotate away from the lifters body a significant distance and this in not a desired trajectory. If the pezzing is violent enough the barbell may continue on its path with such force that the athlete will lose the barbell behind them, or will be forced to jump forward with such force that they will be out of alignment when receiving the barbell. Comparisons of Two Athletes in Performing the Snatch. (The author of this part of the article is Klaus E. Bartonietz, PhD, Schifferstadt Germany. His quotes are italicized)

5 The athlete shown on top is Naim Suleymanoglu, (TUR) and the athlete on the bottom is Antonio Krastev, BUL. The Working area for the knee and hip extensors can differ depending on the size of the athlete. Taller athletes start with more bending of the knee, as shown in position 1 of Krastev. The shorter athlete, Suleymanoglu, begins the first pull from a knee angle that is higher. In the transition from the first to the second pull, shown in positions 3 and 4, the knees go towards the bar and the knee angle is decreased by about 20 degrees. By helping the lifter ease into the second pulling phase while continuing to extend the hips, this action, when performed correctly, results in a barbell movement without any decrease in velocity. Notice the alignment of each athlete at the beginning of the lift. Krastev has his knees, slightly, in front of the barbell, with the barbell over his phalange metatarsal joint, while Suley has his feet and knees behind the barbell. WHAT NEEDS to be seen is that both athletes Shoulders are in alignment with the barbell, neither greatly, forwards or backward and, as a result, the pathways of the bar are well within the acceptable trajectories as stated in the bio-mechanical part of this article.

6 Both athletes jump backwards in the reception phase but Suley is significantly further back than Krastev. The shorter lifter shifts the bar about 72% of the distance utilized by the taller lifter. Therefore differences in the necessary bar velocity are inevitable. A coordination of the separate movements ensures that the trajectory of the weight remains behind the vertical line at all times. HIPS, ANKLES and SHOULDERS. It is of critical importance that coaches, and athletes, pay attention as to what is occurring in the above listed joints while lifting. The hip extensors seem to produce the highest power demands and play a major role in producing an effective pull. If the hips do not perform their task that task is transferred to the knees and the results can be a faster 1 st pull and a slower 2 nd pull, which is not efficient. (Years ago Coach Bob Takano suggested that being in the proper power position might be most important part of a successful lift. (That position is the beginning of the second pull) Bartonietz suggests that hip power production may even affect the efforts of the ankles and wrists as the hips have external force and the ankles and wrists have internal force in the reception phase of the lift. Some coaches believe the ankle does not have much of an influence on performance and that a marked planter flexion is viewed as improper technique. Yet as seen in the figures above there is active planter flexion of the ankles. In fact active opening of the ankles, during the second pull, is essential to vertical acceleration of the barbell and contribute about 10% of the maximum velocity. The ankles show the largest movements of all the joints involved and their power is only 10% lower than that of the knees. It is not enough to turn over and catch a barbell. An intensive shrug of the shoulders must act against the deceleration of the barbell. Bartonietz goes on to state that an effective shrug will produce a positive result in the reception phase of the lift (in other words a big shrug can help prevent against the barbell crashing onto the athlete. A LOOK AT DIFFERENT PULLING STYLES FROM DIFFERENT COUNTRIES

7 As can be seen in the figure above different countries seem to pull differently. The cause of this could be cultural but it could also be due to anthropomorphic measurements. If we can accept that different cultures look different than we must realize that their look may influence their pull. Despite their differences (and that the Armenian s (2) and Hungarians (4) allow the barbell to go in front of the axis as it breaks from the platform) all the lifts fall well within the accepted bio-mechanical principles stated in the article. (Which is that the barbell stays behind the vertical axis of the starting point at the completion of the 1 st pull, 2 nd pull and in the reception phase) A LOOK AT AMERICAN PULLING STYLES All of these trajectories resulted in successful lifts and while 3 of the 5 follow the basic principles of weightlifting bio-mechanics, unfortunately there are small, and hopefully, correctable flaws. In figures 2 and 3 the barbell is in front of the vertical axis throughout the lift. And in all the lifts, save the 4 th, the barbell is in front of the vertical axis in the reception phase. A suggestion here would be that the athlete s performing these lifts are not lifting near the weights that they could be lifting if the proper techniques where being practiced. This can become a serious flaw in the thinking process of both athlete and coach. I can say this from a personal standpoint. If an athlete of mine establishes an IDAHO STATE RECORD they can become cocky in their training, like having an Idaho State Record actually means something. EVERYONE who lifts in Idaho has an Idaho State Record as there are only 15 of us;). I know that in one aspect we can only perform as well as we in the US can perform, but we need to get in a frame of mind that has all of us striving to become better, regardless of what status we may have achieved. The local athlete has to think nationally and a national athlete needs to think internationally. This can be quite the challenge, but one that is worth the effort. The main point is to prevent against complacency.

8 PRACTICAL APPLICATIONS Dr. William Sands has completed anthropomorphic measurements on elite U.S. Gymnasts and in 2004 (When I was working the National Junior Squad Training Camp) he performed those measurements on the team. My hope was that a procedure could be developed that would allow a coach to take an athletes limb measurements and their relationship to one another and then make a comment, to paraphrase the old 1980 s Bangles song, to their athlete You should Walk Like and Egyptian, or Pull Like an Armenian. The actual results suggested a more applicable solution. Collect some pulling data on your athlete and then make the anthropomorphic (limb relationships) changes that will result in the barbell trajectory being within the acceptable pathways. Now that I have convinced everyone who has read this article that your athlete can pull differently then another athlete and still be correct how do we make sure that our athlete is performing the lifts correctly, for them. Using a video camera record your athlete, while lifting. Please make sure that you are, exactly, perpendicular to them. When finished watch the video and place either graph paper or a transparency on the monitor. Put the video on Slow Motion and trace the trajectory of the barbell. (Note. I used to place reflective tape or anything distinct on the end of the barbell to help follow the trace.) Now you have the data you need to make the corrections to allow your athlete to really be the best that they can be. In closing I do apologize for the length of this article but I do feel it is a subject well worth discussing. Actually I hope that it does start a dialogue between coaches and their athletes. So we can improve our athlete s performance. PS. Thank you, Dr. Bartonietz, Dr. John Garhammer, Brian Derwin, Bob Takano, K. Hakkinen, H. Kauhanen, Jim Schmitz, Dr. William Sands, Dr. Michael Stone, and anyone else who sees their thoughts and ideas presented in this article.