First pages:

Abstract: تعد رياضة رفع الاثقال على وجه الخصوص من الفعاليات الرياضية المهمة التي اخذت نصيبا وافرا من اهتمام الباحثين والمهتمين والمدربين من خلال كونها الفعالية الاولمبية, ونظرا لخصوصية الفعالية من حيث تنفيذ الرفعات والسرعة العالية للحركة والتي تعد من اهم سمات هذ | Weightlifting sport is one of the important sport field that get rise interesting from coaches and careers and researchers, because it's one of the Olympics event. In view of the specialist of its requirement like the fast movement and pull of the weight in fastest it's possible that for the motion analysis is needed and the main way to determine , analyses and correction the good and weak points. The aim of this study is to put a modern aspects in Motion analysis field that more accuracy considering the individual differences in performance.And summarized the idea of research in the adoption of a sample of international higher levels in study this variables and to identify the most important variables that may contribute to the development of values significant in evaluating the level of performance, and identify the strengths and weaknesses included sample countries are : (Turkey, Iran, Syria, Iraq) for weightlifter youth and adopted the analysis both of snatch and clean&jerck lifts, (18) youth weightlifter were choosing to record their sub - maximal attempt in both of snatch and clean&jerk, Best attempt was taken to analyze it, Electromyography of skeletal muscle was recorded by (Noraxon) system for agonist and antagonist muscle groups, For analyze we depend on three camera on several sides ( front, side, fron - side). Research goals : 1 - Depend the relative values of measurements of anthropometrics variables to calculate the biomechanical variables of weightlifting barbell and muscular electromyography.2 - Study some muscle groups (agonist - antagonist) to approve the economics of work.3 - Find the contribute rate of anthropometrics, biomechanical variables and muscle electromyography in weightlifting barbell trajectory in snatch and clean&jerk.4 - Identify the relationship between the relative power of the weightlifters and the mechanical variables of barbell motion trajectory.5 - Constructing a model for motor performance in the snatch and clean& jerk, depending on the biomechanical variables and anthropometrics and electrical activity of muscles.Conclusions Researcher concluded by the results of the study : 1. That the adoption of the relative values is more appropriate in the treatment of multiple members of the sample and mixed. 2. Muscle groups on its hinge free movement recorded a few percentage difference in electrical activity between the muscle groups involved and any anti - survival in the high levels of action while the muscle groups work on a limited hinge movement registered the largest percentage difference. 3. Were similar rates of variation in the electrical activity of groups of muscle force and anti - in levels and different values during the phases of the performance of the snatch and jerk as she was the highest values of the first section of the elevation of jerk in the process of ridding the weight of the attraction ground while the highest values for the performance of the snatch in the stages of installation and balance sheet. 4. The lowest percentage difference between (agonist and antagonist) at key stages of progress and the effectiveness of the evidence on the regions of the muscle groups in the course of the performance of the snatch and jerk. 5. That the percentage difference in a variable electrical activity between the top of the muscle groups and anti - labor activity shows the maximum and effective for these groups while the proportion of variation in a variable rate of electrical activity between the muscle groups and anti - labor shows its survival in the level of efficiency and activity. 6. Show that the relative strength of the linked significantly with variable labor and the ability at the same stage during the performance of the snatch and first section of the elevation jerk. 7. The results showed significant correlation with the relative strength of the variable amount of movement to a certain stage during the performance of the snatch while did not show any correlation with this variable in the course of the performance of the first section of the elevation jerk and this is due to the privacy of the performance of each elevation. 8. Relations appeared to link moral force in the course of the relative performance of both lifts with variable kinetic energy in different stages of the lift. 9. Recorded the first distance (Dt1) for the snatch and first section of the clean too closely with the most significant research variables. 10. Second in the distance (Dt2) for the snatch and first section of the elevation jerk did not record significant correlation relationships and clear with the research variables. 11. Different correlations of the moral distance (Dt3) and (Dt4) with the research variables in the course of the performance of the snatch and first section of the elevation jerk. 12. Showed the highest values to the variables of multi - link research in the course of the performance of the snatch in the distance first (Dt1) and the distance the third (Dt3) while the first section of the elevation of the jerk in the distance the third (Dt3) and the fourth distance (Dt4). 13. Concentrated most of the relations of the moral and relational multi high correlation coefficients for the second elevation of jerk during the second distance (Dt6). 14. Gave a lot of research variables following a rates within the limits of levels of mistake, which is accepted implicitly based on the nature of the stage.Recommendations : After the following conclusions the researcher recommended : 1. Adoption of measures to reduce the relative proportions of individual differences in absolute values. 2. Need to follow up real - time performance of the trainees to clarify strengths and weaknesses. 3. Training according to the models with high taking into account individual differences. 4. Need to focus on the electrical activity index enhancer of mechanical work. 5. Attention to training areas and effective lifts that emerged from the study and not to neglect the rest of the stages. 6. Conduct similar studies to include an international sample and the number of muscle groups more. 7. Conduct similar studies to identify the differences between the calculated and the expected results in the variables that require calculating the distance and displacement.