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1.
Fujihara T Gervais P 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(1):34-47
The aim of this study was to investigate the influence of a suspended aid on the reaction forces during a basic skill on pommel horse. Twenty gymnasts performed three sets of 10 circles with and without a suspended aid on a pommel horse under which two force plates were set. The results confirmed that the suspended aid could reduce the magnitude of the pommel reaction forces during circles while maintaining the general loading pattern. On the left hand, the average and peak forces were attenuated to 0.59 body weight (BW) and 0.85 BW from 0.76 BW and 1.13 BW, respectively. The right hand experienced slightly larger forces with no-aid trials, but the asymmetry between the hands decreased with the aid. Despite a relatively large variability, all gymnasts experienced smaller impact peak forces with the aid. A suspended aid is most commonly used for a beginner gymnast as an introduction to pommel horse exercises. However, this study confirmed that it can also be useful for all levels of gymnasts who would like to practice pommel horse exercises with reduced pommel reaction forces for a purpose such as a progression for learning a new skill, control of training volume, or rehabilitation. 相似文献
2.
A suspended aid is popular for learning circles and for refining circle technique on pommel horse. The aim of this study was to investigate the effect of using a suspended aid on the biomechanical characteristics of circles. This first study focused specifically on the spatio-temporal characteristics of circles. Eighteen gymnasts performed three sets of 10 circles with and without a suspended aid on a pommel horse under which two force plates were set. Three-dimensional coordinates were acquired using 13 Qualisys motion tracking cameras operating at 100 Hz. The results showed that circles with the aid were characterised by a smaller body flexion angle, a greater shoulder angle, a greater ankle circle diameter, earlier hand releases, and a longer total duration. In contrast, the body lateral flexion angle, the arm-leaning angle, and the shoulder circle diameter remained relatively similar to circles without the aid. It was confirmed that circles with the aid actually appeared to be more desirable in terms of the movement amplitude. In this sense, a suspended aid could function as spotting, which is often used for a progression to learn gymnastics skills and to let gymnasts experience a desired movement pattern. 相似文献
3.
In the third study of this series, we examined how circles with a suspended aid would vary depending of the gymnast's level of expertise. We analysed circles with the aid performed by three groups of eight gymnasts: expert, intermediate, and developing groups. The gymnasts for the expert and intermediate groups were selected from the previous studies based on judges' evaluation of their non-aid circles. The developing group of eight gymnasts, who were unable to perform circles on pommel horse without an aid, were added to this study and performed three sets of 10 circles on the pommel horse with the aid. Discriminative biomechanical variables identified in the previous two studies were used to compare circles with the aid among the three groups. As a result, the expert group demonstrated a larger pommel reaction force and a smaller aid reaction force than the other two groups, implying that they were less dependent on the aid. The smaller aid reaction force resulted in a smaller net hip joint moment. Furthermore, the expert group showed a shorter total duration and a greater shoulder excursion. In summary, the suspended aid can be used in a progressive manner depending on the gymnast's level of expertise. 相似文献
4.
This is the second study of the series, and its aim was to investigate the influence of using the suspended aid on circle kinetics. In addition to the kinematic data recorded for part one (Fujihara & Gervais, 2012), the pommel reaction forces and the force applied from the suspended aid (aid reaction force) were analysed in relation to the motion of a whole-body mass centre. The hip joint moment was also computed by combining all segments in the lower extremities into a single rigid segment. Generally, the use of the aid changed the magnitude of the mass-centre trajectory or horizontal pommel reaction forces but not their patterns. The results also showed that the net hip joint moment was altered during circles with the aid. In summary, a suspended aid can be used as a progression for a variety of goals because it allows gymnasts to practise circles which would not be possible without the aid. When a suspended aid is used, however, practitioners should be aware of the possible kinetic alteration caused by the external force from the aid. 相似文献
5.
Abstract This is the second study of the series, and its aim was to investigate the influence of using the suspended aid on circle kinetics. In addition to the kinematic data recorded for part one (Fujihara & Gervais, 2012), the pommel reaction forces and the force applied from the suspended aid (aid reaction force) were analysed in relation to the motion of a whole-body mass centre. The hip joint moment was also computed by combining all segments in the lower extremities into a single rigid segment. Generally, the use of the aid changed the magnitude of the mass-centre trajectory or horizontal pommel reaction forces but not their patterns. The results also showed that the net hip joint moment was altered during circles with the aid. In summary, a suspended aid can be used as a progression for a variety of goals because it allows gymnasts to practise circles which would not be possible without the aid. When a suspended aid is used, however, practitioners should be aware of the possible kinetic alteration caused by the external force from the aid. 相似文献
6.
Toshiyuki Fujihara Takafumi Fuchimoto Pierre Gervais 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(1):22-38
The aim of this study was to analyse the principal mechanics of circles. Seventeen university male gymnasts performed circles on an instrumented pommel horse model that enabled the pommel reaction forces to be recorded at 1000 Hz with two force plates. The circles were also videotaped using two digital video cameras operating at 60 frames per second. During circles, the vertical component of the reaction forces peaked in the double-hand support phases. Changes in the velocity of the centre of mass corresponded to the change in the tangential components of horizontal reaction forces. The velocity of the centre of mass had its peaks in the single-hand support phases and its local minimums in the double-hand support phases. The velocity of the ankles and that of the centre of mass of the head and trunk were minimal in the single-hand support phases and were maximal in the double-hand support phases. These results suggest that the circles were composed of vertical movements and two kinds of rotations: rotation of the centre of mass and rotation of the body itself about the centre of mass. These two kinds of rotations, which influence the legs' rotational velocity, are phase dependent. To further our understanding of circles, research on circles in different orientations on the pommel horse will be beneficial. 相似文献
7.
《European Journal of Sport Science》2013,13(1):21-30
Abstract One of the most fundamental skills on the pommel horse is double leg circles (circles). Circles can be performed on all parts of the pommel horse. It was hypothesized that the different sets of physical constraints of the apparatus require a gymnast to adapt circles technique. The purpose of this study was to quantify how gymnasts modify their technique during circles to accommodate different physical obstacles due to different support surfaces and body orientations. To investigate these adaptations, a comparison of the two most common circles on pommel horse – namely, circles in cross support (cross-circles) and circles in side support (side-circles) – was carried out. Seven elite male gymnasts performed three sets of 10 cross-circles and side-circles on a pommel horse. Three-dimensional coordinates were acquired using 12 Qualisys ProReflex motion tracking cameras operating at 120 Hz. Temporal characteristics, the motion of the centre of mass, and the body angles – flexion and lateral flexion – were analysed. We found that cross-circles took less time to complete a single circle (0.92±0.02 vs. 0.95±0.02 s), had a smaller ratio for the rear support phase (0.15±0.02 vs. 0.18±0.03), a narrower supporting-hand distance (0.33±0.03 vs. 0.52±0.00 m), greater flexion of the body over the rear support phase (44±12° vs. 27±8°), and less lateral flexion of the body over the single-hand support phase (entry: 20±5° vs. 35±3°; exit: 26±4° vs. 33±4°) than side-circles. Our results suggest that gymnasts adapt their technique to the physical constraints imposed by the shape of the pommel horse and the location and orientation of the circles. Cross-circles were characterized by a high rear support position with a narrower hand-spacing, which would require excellent shoulder flexibility and strength. Consequently, lack of these traits may explain the need for greater body flexion in cross-circles than in side-circles during rear support. Understanding the technical differences will facilitate an effective transfer of the technical similarities among different types of circles. 相似文献
8.
In this study, we investigated whether video modelling can enhance gymnasts' performance of the circle on a pommel horse. The procedure associated expert-modelling with self-modelling and quantitative performance analysis. Sixteen gymnasts were randomly assigned to one of two groups: (1) a modelling group, which received expert- and self-modelling, and performance feedback, or (2) a control group, which received no feedback. After five sessions of training, an analysis of variance with repeated measures indicated that the gains in the back, entry, front, and exit phases of the circle were greater for the modelling group than for the control group. During the training sessions, the gymnasts in the modelling group improved their body segmental alignment during the back phase more quickly than during the other phases. As predicted, although both groups performed the same number of circles (300 in 5 days, with 10 sequences of 6 circles), the modelling group improved their body segmental alignment more than the control group. It thus appears that immediate video modelling can help to correct complex sports movements such as the circle performed on the pommel horse. However, its effectiveness seemed to be dependent on the complexity of the phase. 相似文献
9.
Abstract In this study, we investigated whether video modelling can enhance gymnasts' performance of the circle on a pommel horse. The procedure associated expert-modelling with self-modelling and quantitative performance analysis. Sixteen gymnasts were randomly assigned to one of two groups: (1) a modelling group, which received expert- and self-modelling, and performance feedback, or (2) a control group, which received no feedback. After five sessions of training, an analysis of variance with repeated measures indicated that the gains in the back, entry, front, and exit phases of the circle were greater for the modelling group than for the control group. During the training sessions, the gymnasts in the modelling group improved their body segmental alignment during the back phase more quickly than during the other phases. As predicted, although both groups performed the same number of circles (300 in 5 days, with 10 sequences of 6 circles), the modelling group improved their body segmental alignment more than the control group. It thus appears that immediate video modelling can help to correct complex sports movements such as the circle performed on the pommel horse. However, its effectiveness seemed to be dependent on the complexity of the phase. 相似文献
10.
In this study, we examined the effectiveness of auditory concurrent feedback on body segmental alignment during the circle movement performed on a pommel horse. Eighteen gymnasts were assigned to one of two groups: a concurrent auditory feedback group (experimental) or a control group that received no concurrent feedback. After 2 weeks of training (300 circles), the body segmental alignment (BSA) of the experimental group had improved by 2.3% between the pre test (85.7 +/- 4.8% BSA(max)) and the post test (87.7 +/- 4.0% BSA(max)). Furthermore, the results of a retention test administered 2 weeks after the post test revealed no decline in performance for the experimental group. No gains in body segmental alignment were found for the control group. It was concluded that augmented auditory feedback made available in real time can be used to correct complex movements, such as the circle movement on a pommel horse, and does not appear to lead to information-dependence despite the frequent administration of feedback. The auditory signal available in real time could help gymnasts to become more objective about their own intrinsic information necessary for the refinement of the circle movement. 相似文献
11.
采用文献资料和录像观察法,分析第41届和42届世界体操锦标赛鞍马单项决赛参赛运动员完成的成套动作,得出伦敦奥运周期鞍马动作的发展趋势,以期为我国男子体操队备战过程中鞍马训练提供依据。研究表明：世界优秀鞍马选手对动作类型的选择表现出更加集中的趋势;第Ⅰ组别动作逐渐向李宁和反交叉转体90°经单环起倒立落下成骑撑集中;马桥尔打滚成为第Ⅱ组别动作的首选难度动作;第Ⅲ组别集中在马桥尔前移和斯维多后移高度两个动作;第Ⅳ组别动作的使用将以E组或D组Flops、吴国年、（环中或马头）俄式挺身转体,以及E组或D组Flop组合为主;第Ⅴ组别动作将以D组或E组难度的斯托克里起倒立下为首选。 相似文献
12.
Reaction forces experienced by gymnasts swinging on the high bar may be determined indirectly using inverse dynamics analysis
or may be measured using strain gauges. The accuracy of inverse dynamics analysis may be poor because of errors in the estimated
inertia parameters and in the accelerations obtained from digitized data. On the other hand the use of strain gauges is not
always possible in elite competition. This paper presents a method for estimating the reaction forces based on the linear
displacements of the bar.
The bar was modelled as a point mass attached to horizontal and vertical linear springs (obeying Hooke’s law) with stiffness
coefficients determined from static loading. The stiffness coefficients of the bar were determined with three different tensions
in the stabilizing cables of the high bar. A force and video analysis of backward giant circles was performed. Estimates for
the reaction forces were obtained by multiplying the bar displacements from the video analysis by the stiffness coefficients
determined from the static loadings. Comparisons were made between the estimated reaction forces and the reaction forces recorded
using strain gauges attached to the high bar.
Varying the tension in the stabilizing cables of the high bar did not effect the stiffness of the bar. Root mean squared differences
between estimated and recorded reaction forces were on average within 99 N for three ‘regular’ and three ‘accelerated’ giant
circles. This was less than 3.5% of the range of forces recorded. The bar displacement method was able to estimate the peak
reaction forces to within 7% on average, which compares favourably with 24% reported by Gervais (1993) using inverse dynamics. 相似文献
13.
Roman Farana Gerda Strutzenberger Timothy Exell Jiri Skypala Huw Wiltshire Gareth Irwin 《Journal of sports sciences》2019,37(13):1449-1456
The aim of the study was to determine if sex differences exist in the key elbow and wrist joint injury risk factors during different cartwheel (CW) and round-off (RO) techniques performed by young male and female artistic gymnasts. Sixteen active young gymnasts (8 males and 8 females) performed 30 successful trials of CW and RO with three different hand positions (parallel (10), T-shape (10) and reverse (10)). Synchronised kinematic and kinetic data were collected for each trial. Two-way repeated measures ANOVA (3 × 2, technique × sex) and effect-sizes (ES) were used for statistical analysis. In conclusion, female gymnasts exhibited greater normalised peak vertical ground reaction forces (VGRF), elbow and wrist compression forces and elbow internal adduction moments during CW and RO skills compared with male gymnasts. In both sexes, the parallel and reverse techniques increased peak VGRF, elbow and wrist compression forces and the elbow internal adduction moment. Increased elbow flexion resulted in decreased peak VGRF, elbow compression forces and elbow internal adduction moment. Injury risk factors including elbow extension and internal adduction moment with axial compression force suggest that a CW and RO in reverse and parallel techniques can be hazardous especially for young female gymnasts. 相似文献
14.
This study was carried out to design, construct and assess a training aid to assist in the learning of a backward handspring.
A backward handspring is often the first backward dynamic skill gymnasts will learn and so its performance can be accompanied
by anxiety. International high performance coaches were surveyed to establish the key coaching requirements of a backward
handspring training aid. A video analysis of the skill was used to determine characteristic dimensions of the skill, and these
were used in the design of the training aid. The aid was designed and manufactured in accordance with European Standards for
safety. The device’s safety for use in supporting the backward handspring was confirmed through testing. The assessment of
the training aid using 11 gymnasts showed that it permitted a safe dynamic performance; provided support; did not obstruct
technically good performances; allowed progressive use by novices without additional coach support; and was adjustable for
gymnasts of various size and ability. When assessed against other training aids, it was the only aid that fulfilled all of
the key coaching requirements. 相似文献
15.
我国少年男子体操运动员腕部运动损伤的调查分析 总被引：2，自引：0，他引：2
对我国优秀少年男子体操运动员腕部运动损伤的情况进行了调查。结果表明,运动员的损伤主要为三角纤维软骨盘损伤,过多的支撑练习是造成损伤的主要原因,腕部的损伤多发生在鞍马、双杠和自由操项目中。 相似文献
16.
Weight bearing (WB) activity is important for healthy skeletal development. The magnitude of loading during WB activities, especially upper limb impacts, has yet to be quantified in children. This study quantifies ground reaction forces (GRF) experienced by children performing WB activities and examines the contribution of body weight (BW) to GRF. Fifty children, aged 8–12 were recruited (34 males). GRF were measured using force plates during 20 upper and lower limb activities (such as landing on the feet and hands). Sex differences in GRF and associations between peak force and BW were examined using independent sample t-tests and linear regressions (p < 0.05), respectively. Lower limb GRF varied from 2-6x BW with no significant sex differences. GRF during upper limb activities varied from 1/3–1.7x BW with males experiencing significantly greater GRF for 25% of activities. BW was significantly associated with peak force in almost all activities; however, GRF variation explained by BW was wide-ranging across activities and not dependent on limb or activity type (static vs dynamic). Therefore, factors other than BW, such as technique, may be important in determining forces experienced by children performing WB activity and should be considered when choosing activities for WB activity interventions. 相似文献
17.
Abstract Scores in artistic gymnastics are subject to changes in the rules that occur each Olympic cycle as outlined in the Code of Points, because rules influence the composition of routines and therefore performance. The aim of this study was to identify the most important routine apparatus for success in a World competition. The data were the official results for the 478 gymnasts (262 men, 216 women) who competed in the 43rd Artistic Gymnastic World Championships in 2011 in Tokyo, Japan. The factors least influenced by the technical standard of competitors were performance scores on uneven bars and balance beam for women, and those on pommel horse for men. For uneven bars, balance beam, and pommel horse, scores were consistently good predictors of final standing. Our results suggest that high scores on these apparatus have a greater influence on overall performance than scores on the other apparatus, regardless of the competitors' standard. 相似文献
18.
Roman Farana Timothy Exell Gerda Strutzenberger Gareth Irwin 《European Journal of Sport Science》2018,18(3):423-430
Biophysical loading of the elbow and wrist is a potential reason for chronic lesions in gymnastics and present a real concern for coaches, scientist and clinicians. Previous research has identified injury risk factors during round-off (RO) skills in elite female gymnasts. The aim of this study was to investigate key elbow and wrist joint injury risk factors during different techniques of fundamental cartwheel (CW) and RO skills performed by young female artistic gymnasts. Seventeen active young female gymnasts performed 30 successful trials of both CW and RO from a hurdle step with three different hand positions (parallel (10), T-shape (10) and reverse (10)). Synchronised kinematic (240?Hz) and kinetic (1200?Hz) data were collected for each trial. One-way repeated measures ANOVA and effect size (ES) were used for statistical analysis. The results showed statistically significant differences (P?0.8) among hand positions for peak vertical ground reaction force (VGRF), peak elbow compression force, peak wrist compression force, elbow internal adduction moment and wrist dorsiflexion angle. In conclusion, the parallel and reverse techniques increase peak VGRF, elbow and wrist compression forces, and elbow internal adduction moment. These differences indicate that the parallel and reverse techniques may increase the potential of elbow and wrist injuries in young gymnasts compared with the T-shape technique; this is of particular importance with the high frequency of the performance of these fundamental skills. 相似文献
19.
王长青 《沈阳体育学院学报》2007,26(6):113-115
对2006年全国体操锦标赛中鞍马项目成套动作及完成情况进行分析。结果表明,我国运动员具有夺取世界冠军的实力,但整体完成情况欠佳;高难动作类型偏,有失分点动作;应提高成套动作的起评分,注重技术的全面发展,加强专项素质训练。 相似文献
20.
Cristine Lima Alberton Paula Finatto Stephanie Santana Pinto Amanda Haberland Antunes Eduardo Lusa Cadore Marcus Peikriszwili Tartaruga 《Journal of sports sciences》2015,33(8):795-805
The purpose was to analyse the vertical ground reaction forces (Fz) of head-out aquatic exercises [stationary running (SR), frontal kick (FK), cross-country skiing (CCS), jumping jacks (JJ), adductor hop (ADH) and abductor hop (ABH)] at two cadences in both aquatic and dry land environments. Twelve young women completed two sessions in each environment, each consisting of three exercises performed at two cadences (first and second ventilatory thresholds – C1 and C2, respectively). Two-way and three-way repeated measures analysis of variance were used to the statistical analysis. The results showed that the peak Fz and impulse were significantly lower in the aquatic environment, resulting in values from 28.2% to 58.5% and 60.4% to 72.8% from those obtained on dry land, respectively. In the aquatic environment, the peak Fz was lower and the impulse was higher at the C1 than at the C2. Furthermore, it was observed that SR and FK (0.9–1.1 BW) elicited a significantly higher peak Fz values compared to the ADH and JJ exercises (0.5–0.8 BW). It can be concluded that the aquatic environment reduces the Fz during head-out aquatic exercises. It should be noted that its magnitude is also dependent on the intensity and the identity of the exercise performed. 相似文献