Variation in Barbell Position Relative to Shoulder and Foot Anatomical Landmarks Alters Movement Efficiency
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Original Research Variation in Barbell Position Relative to Shoulder and Foot Anatomical Landmarks Alters Movement Efficiency SHELLEY HANCOCK†1, FRANK WYATT‡2, and LON KILGORE‡3 1The Center for Preventative Medicine, La Palestra, New York, NY, USA, 2Department of Athletic Training & Exercise Physiology, Midwestern State University, Wichita Falls, TX, USA, 3Institute for Clinical Exercise & Health Science, University of the West of Scotland, Hamilton, Scotland, UK ‡Denotes professional author, †Denotes graduate student author ABSTRACT International Journal of Exercise Science 5(3) : 183-195, 2012. The purpose of this study was to determine if either of the two deadlift starting positions would yield a more efficient movement than the other; (1) the traditional Olympic lifting and deadlift starting position with the barbell over the metatarsalphalangeal joint and under the acromioclavicular joint or (2) an experimental alignment with the bar over the navicular bone and under the most inferior and medial aspect of the scapular spine. This second starting position, developed as a teaching convention, differs from the historical alignment of toes-barbell-shoulder joint and is also proposed to reduce horizontal displacement of the bar thus minimizing the amount of work needed to complete the movement. It was hypothesized that the experimental alignment would produce a more efficient pulling movement compared to a traditional starting alignment. Efficiency was defined as a barbell path approaching linear movement, with larger horizontal displacements being considered less efficient than smaller displacements. Six intermediate level weightlifters, 23.8 ± 1.9 years of age, 164.7 ± 7.9 cm in height, 81.5 ± 31.9 kg in body mass, completed a series of deadlifts under both alignment conditions with 90% of their self-reported 1RM (169.0 ± 58.17 kg). Posterior horizontal barbell displacement was measured by video- analysis. In the traditional alignment (metatarsalphalangeal-bar-acromioclavicular) displacement was 66.7 ± 12.9 mm and was 37.5 ± 13.7 mm in the experiment alignment (navicular-bar-scapular spine). The noted 43.8% reduction (29.2 mm) in horizontal displacement in the experimental alignment condition was statistically significant (p = 0.0001) and supports the hypothesis in regards to improved lifting efficiency. KEY WORDS: Strength performance, weight training, exercise anatomy INTRODUCTION lifting objects in competition are quite meaningful, descriptions of the human Strong men have competed in informal and movements used to lift implements or formal competition throughout history and weights has not been a consistent feature of this has been well documented in available literature. In essence, a critical archaeological and historical records. While analysis and resultant description of the depictions and cursory references to men elements of proper lifting technique is ANATOMICAL ALIGNMENT AND DEADLIFT EFFICIENCY missing. It is likely that this pedagogic and press, the snatch, and the clean & jerk. Each scientific omission is a product of lift was discriminated from the others by competition format, as historically the technique in which it was completed. whomever successfully raised the heaviest The press consisted of pulling the bar up weight over head by any means won. This onto the shoulders followed by a second approach to lifting technique and movement where the shoulders and elbows competition became problematic at the 1896 were extended thus raising the weight Olympics, the first modern Olympic overhead. The snatch was a single Games. In that competition, Launceston movement lift requiring the weight to be Elliot of Scotland and Viggo Jensen of pulled from the floor up to completely Denmark tied for first place by lifting the extended arms overhead. The clean & jerk, same weight in a two-handed lift, 110 kg. as its name implies, is a two movement lift. At the time there were no uniform rules in In the first movement, the barbell is pulled place regarding the techniques to be used in to the shoulders, as in the first movement of competition. As a result of the tie, the the press, this is the "clean" portion. In the observing official, the Crown Prince of jerk, the knees and hips are used to produce Greece, ruled that Jensen had lifted the a very rapid and shallow squat and weight in a better style and was thus extension that propels the barbell overhead awarded the gold medal. This was later where it is caught on extended shoulders protested by the Scottish contingent on the and elbows. grounds that no documentation was present as to what was considered a “better It is at this point in history that the style”. The appeal by the Scots was evolution of the problem addressed in this unsuccessful (3). project begins. The official rules regarding all three lifts prohibited touching of the bar Shortly after the first Olympic games, a against any part of the body except for the governing body, the International hands that grasped it and the shoulders on Weightlifting Federation (IWF) was created which the bar transiently rested upon in the to oversee and regulate the sport of press and clean & jerk (1). The rules specific weightlifting (17). From its creation in 1905 to the pulling of the bar from the floor until the present day, the IWF develops and disallowing any contact with the body was enforces the technical rules for the sport, a limitation in performance. Elementary contested in and between 167 affiliated physics mandates that the mass of the nations. To prevent occurrences similar to barbell will move towards the center of the 1896 tie, the IWF created a set of mass of the body supporting it, to a point competitive rules and regulations for each where the combined center of mass (barbell competitive lift. At the beginning these and human) is supported over a point rules were broadly constructed as there midway between its most anterior and were many different lifts included in posterior points of support. Because of the Olympic competition, both dumbbell based prohibition of thigh-bar contact, the and barbell based. Eventually the menu of position a lifter of the era would assume lifts were narrowed to three barbell lifts relative to the bar was to place the toes that all began with the weight on the floor (phalanges) or the ball of the foot and finished with the weight overhead, the (metatarsal-phalangeal joint) directly under International Journal of Exercise Science http://www.intjexersci.com 184 ANATOMICAL ALIGNMENT AND DEADLIFT EFFICIENCY the bar. This made the distance the bar had during the initial pulling movement from to cover before it touched the legs the the floor. maximum possible. Any more of a forward displacement (beyond the toes) A perusal of the literature relevant to the significantly reduces the efficiency of the pulling motion in weightlifting operating lever arms to a point that only demonstrates a very limited research pool. lighter weights can be lifted. Virtually all published accounts of pulling research focus on the path the bar takes Another part of the bar-thigh touch during Olympic style weightlifting without solution of the time was in joint movement consideration of the anatomical sequence. Under the early and mid- construction and physical relationships of twentieth century rules, the actual pulling the body that is lifting it. Only a few papers motion used by lifters consisted of nearly consider the pulling lift examined here, the simultaneous knee and hip extension. The Deadlift, in any manner (5, 9,14). Although combination of a bar-forward starting the dearth of literature in regards to the position and simultaneous joint extension topic is perplexing, it is understandable. set up a shallow forward arc in barbell path There is no history of weightlifting that prevented the bar from coming in performance research being supported by contact with the thighs. grants from governmental or private funding agencies, as strength and sport As the quest to lift more and more weight performance have been historically thought continued, the rules were softened or to be irrelevant to most health and evolved. By the mid-1960’s, it had become commercial research enterprises, or at least legal for the bar to come in contact with the thought to be less important than shins and the thighs. This provided a endurance and thus less fundable. performance advantage as the barbell's mass could now be placed in a more It was not until 2007 that a consideration of favorable position in order to apply more combined human anatomy, physics, and muscular force to it. An interesting thing pulling a barbell off of the floor received happened in regards to lifting technique, or even cursory attention. In the second rather did not happen that may have edition of the book Starting Strength (15), a limited further increased lifting conceptual framework was proposed for an performance. Instead of modifying the bar- association existing between the foot, the foot spatial relationship at the start of the bar, and the scapula in any pulling motion lift to reflect a more efficient technique, off of the floor. Originally conceived as a efficiency defined as movement method of teaching reliable, repeatable, and approaching a straight line, weightlifting efficient pulling technique, the scapular coaches continued to, and still to this day, alignment model the authors proposed teach a bar over toes and shoulder joint intended to both normalize teaching over the bar starting position that was methods and to improve the efficiency and appropriate in the first half of the twentieth performance in the deadlift. The century (6). A start position that is known cornerstone of the teaching technique was to induce rearward horizontal displacement placing the bar over the mid-foot and under the middle of the scapular spine, a straight International Journal of Exercise Science http://www.intjexersci.com 185 ANATOMICAL ALIGNMENT AND DEADLIFT EFFICIENCY line connecting the three points.