Dr.Hab. I.P. Sivokhin¹
Professor, PhD V.F. Skotnikov²
PhD N.A. Ogienko¹
Associate Professor, PhD A.I. Fedorov³
I.A. Shilov^1
1Kostanay State Pedagogical Institute, Kostanay, Kazakhstan
²Russian State University of Physical Education, Sports, Youth and Tourism (SCOLIPE), Moscow
³South Ural State University (National Research University), Chelyabinsk       

Keywords: weightlifting, chest lift element, biomechanics rating tests, technical excellence system.

Background. Technical progress and special physical qualities excelling systems give a growing priority to the modern instrumental test methods to accurately rate and analyze the movement biomechanics [1, 2, 3, 4, 5]. The study topic appears to be highly relevant due to the fact that the classical clean and jerk technique is successful only when its chest lift element is technically excellent to facilitate the jerk completion.

Objective of the study was to experimentally test benefits of a new biomechanical test model to rate progress of elite weightlifters’ in the technical mastery excellence process.

Methods and structure of the study. At the first stage of the study, the Kazakhstan national weightlifting team members (n=13, including 8 males and 5 females) competing in the 2013 World Universiade in Kazan were subject to the video captures and analyses. At the second stage, athletes from group 1 (n=5, including 1 male and 4 females) were sampled for a special study. The clean an jerk movement (including chest lift) biomechanics were tested and profiled again in 2015 during the precompetitive training cycle prior to the World Championship in Houston, USA. The chest lift trajectory was recorded and analyzed by a special computerized tests system including a video-camera and an emitter fixed on the barbell butt, with the test data used to compute the movement kinematics [8].

The first-stage study data and mathematical analysis (2013) were used to find the factors of influence on the movement technique with the relevant biomechanics [5] and to select the following variables for the study purposes:

– Maximal absolute and relative power in the final acceleration phase;

– Weight movement deceleration in the third phase;

– Maximal weight speed in the final acceleration phase;

– Weight height at the maximal speed point; and

– Distance between the maximal weight lift point and the squat fix point.

The above rates were assumed as the most informative for the competitive performance rating in the clean and jerk lift event – albeit the relevant correlations can unlikely reveal the kinematical logics when it comes to the effects the movement biomechanics on the competitive performance. To find such logics, one needs to profile variations of the independent (biomechanical) variables versus those of the dependent variables (competitive success rates) to objectively assess the causes and effects. With this purpose in mind, we run an educational experiment to test the new biomechanical test model to rate progress of elite weightlifters’ in the technical mastery excellence process.

In the efforts to improve the chest lift element execution technique, we were focused on the new model effects on the movement biomechanics. We widely used the traditional education tools including explanations, execution video replays, basic conditioning/ corrective exercises, motor goals settings and verbal execution controls and ratings. The trainings were focused on the explosive strength building practices to ensure a target growth of the fast muscular fibers in the muscle groups critical for success in the event [10, 4]. The effect was attained by a gradual growth of the training workloads on the target fast muscular fibers [6] and the relevant creatine-phosphate energy generation mechanisms [7, 9].

Results and discussion. The pre- versus post-experimental group chest lift execution quality test averages showed significant progresses in some of the key execution rates indicative of the group technical improvements in this element. The movement dynamics rated by the relevant maximal/ relative power rates was found to significantly grow – that may be interpreted as indicative of the startup explosion quality improvements achieved by every subject. Thus the weight speed in the final acceleration phase was tested to grow by 0.24 ms/с (р<0.01) to improve the movement pacing element. The weight height at the maximal-speed point was tested to grow by 0.15 m (р<0.05) – that is indicative of the chest lift execution quality improvement. The maximal absolute startup explosion power was tested to grow by 1000 W (р<0.01); and the maximal relative startup explosion power by 12.5 W/kg (р<0.01). And the maximal squat lift height was tested to grow by 0.07 m (р<0.05).

The above growths in the movement biomechanics were associated with the increased height of the weight lift in the squat phase to contribute to the competitive progress. The progress analysis for the period of 2013-15 estimated the group progress in the chest lift element at 15.2kg (р<0.001). The progress may be attributed to the technical improvements that make it possible to mobilize the motor resource efficiently in the pull, explosion and squat phases, with the same weight requiring notably less effort in at least the pull and explosion phases.

Furthermore, the study found a few skill-level-specific typical errors easily detectable by the integrated movement test technologies – and hardly if ever read by the traditional visual controls. The most serious errors were found in the movement dynamics in the peaking phase when the peaking efforts are imperfectly harmonized in transition from one lift phase to the other. Such errors were found to largely occur due to the dynamic accents being shifted in transition from phase 3 to phase 4 (explosion move) with the element execution flow being disrupted.

The new biomechanical model testing experiment found the model being beneficial as verified by the growth of weight speed in the final acceleration phase and growth of weight fix point height associated with growth of the absolute and relative power rates in the explosion phase. The movement biomechanics showed progress in the explosion phase verified by the actual competitive successes in the classical clean jerk events. Analysis of the chest lift biomechanics generated by the study versus the model characteristics made it possible to efficiently manage the training process in this competitive event. The new biomechanics test model helped correct the clean and jerk technique and, hence the overall technical mastery. The Experimental Grouped was tested with a significant progress in the chest lift element execution quality, reductions in the serious error rates and improved competitive performances. The progress in the chest lift execution mastery contributed to the group successes in the top-ranking competitions, including 1 gold medal in the 2014 Asian Games; silver medals in the 2014/ 2015 World Championships; and 1 silver medal, 1 bronze medal and the fourth and fifth places on the scoreboard at the 2016 Olympic Games. 

Conclusion. The biomechanical test model to rate progress of elite weightlifters was found beneficial as verified by the sample progress in a variety of the classical jerk technique efficiency rates and the competitive accomplishments in the World Championships, Asian and Olympic Games.

References

1. Krasov E.A. Struktura spetsialno-vspomogatelnyih uprazhneniy i pod'ema shtangi na grud [Structure of special auxiliary exercises and weight lifting to chest]. PhD diss.. Moscow: SCOLIPE publ., 1982. 22 p.
2. Medvedev A.S. Sistema mnogoletney trenirovki v tyazheloy atletike [Long-term training system in weightlifting]. Trainer's guide. Moscow: Fizkultura i sport publ., 1986, 272 p.
3. Medvedev A.S., Lukashev A.S., Ismailov I.S. Osobennosti uprugoy deformatsii grifa v tolchke pri pod'eme shtangi na grud [Features of bar elastic deformation in clean and jerk]. Teoriya i praktika fiz. kultury, 1990, no. 5, pp. 43-46.
4. Sivokhin I.P., Skotnikov V.F., Khlystov M.S. et al. Biomekhanicheskaya kharakteristika tehniki klassicheskih uprazhneniy elitnykh tyazheloatletov v usloviyakh sorevnovaniya [Biomechanical characteristics of classic elite weightlifting techniques in competitions]. Olimpiyskiy sport i sport dlya vsekh [Olympic sport and sport for all]. Proc. XVIII International Scientific Congress devoted to the 2017 World Winter Universiade. October 1-4, 2014, Almaty: KazAST publ., 2014, v. 2,pp. 435-438.
5. Sivokhin I.P., Skotnikov V.F., Prikladov Ya.V. Analiz biomekhanicheskikh faktorov effektivnosti tekhniki pod'ema shtangi na grud pri vypolnenii klassicheskogo tolchka [Analysis of biomechanical factors of effectiveness of clean and jerk technique]. Nauka i sport: sovremennyie tendentsii. 2015. no. 2 (v. 7), pp. 110-114.
6. Sivokhin I.P., Skotnikov V.F., Komarov O.Yu. et al. Effektivnost trenirovochnoy nagruzki alaktatnoy napravlennosti v podgotovke elitnykh tyazheloatletov [Benefits of alactate training processes for elite weightlifters' training systems]. Teoriya i praktika fiz. kultury, 2017, no, 3, pp. 26-29.
7. Sivokhin I.P., Skotnikov V.F., Tapsir M. et al. Dinamika izmeneniya laktata krovi u tyazheloatletov vysokoy kvalifikatsii v vosminedelnom tsikle podgotovki [Lactate dynamics in elite weightlifters during eight weeks of training]. Moscow. Teoriya i praktika fiz. kultury, 2017, no. 1, pp. 21-28.
8. Shalmanov A.A., Skotnikov V.F., Panin A.V. Kinematika i dinamika dvizheniya shtangi u tyazheloatletov vysokoy kvalifikatsii v usloviyakh sorevnovaniy [Kinematics and dynamics of bar movement in elite weightlifters in competitions]. Olimp publ., 2012. no. 2-3, pp. 27-31.
9. Jansen Peter. ChSS, laktat i trenirovki na vyinoslivost [HR, lactate and endurance training]. Transl from Engl.. Murmansk: Tuloma publ., 2006, 160  p.
10. Saumann W. Biomechanical Research in to Weightlifting. World Weightlifting. 1985, no. 4, pp. 36–37.

Corresponding author: sivokhin_i_57@mail.ru

Abstract

The study analyzes benefits of a new biomechanical test model to rate technical progress of elite weightlifters’ in the sport excellence trainings with a special priority to the factors of influence on the execution and errors. Benefits of the model were tested by a two-stage experiment. In the first stage of the study, subject to the performance video captures and analyses were the Kazakhstan national weightlifting team members (n=13, including 8 males and 5 females) competing in the 2013 World Universiade in Kazan. In the second stage, sampled for a special study were athletes from group 1 (n=5, including 1 male and 4 females). The first stage was designed to find the key factors of influence on the chest lift element execution by analyses of the movement biomechanics, with the test data further used to develop the new technical excellence model and test it by experiment. The biomechanical test model to rate progress in elite weightlifting sport was found beneficial as verified by the sample progress in the classical jerk technique execution quality test rates and the actual competitive accomplishments in the World Championships, Asian Games and Olympic Games.