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1.
Abstract

The aim of this study was to investigate the convergent and predictive validity of two skill tests that examine the ability of golfers to hit accurate approach-iron shots. Twenty-four high-level golfers (handicap = 2.6 ± 1.7) performed the Nine-Ball Skills Test (assesses the ability to shape/control ball trajectory with high accuracy) and the Approach-Iron Skill Test (assesses the ability to hit straight shots from varying distances with high accuracy). Participants then completed at least eight rounds of tournament golf over the following 90 days and reported an indicator of approach-iron accuracy (per cent error index). A moderate correlation (r = 0.50, P < 0.05) was noted between scores for both tests. Generalised estimating equations, using two covariates (lie of the ball and distance to hole), were used to determine model fit and the amount of variance explained for tournament per cent error index. Results showed that the Approach-Iron Skill Test was the slightly stronger predictor of on-course per cent error index. With both test scores considered together, a minimal amount of additional variance was explained. These findings suggest that either of the tests used individually or combined may be used to predict tournament approach iron performance in high-level golfers.  相似文献   

2.
Currently, there is a lack of appropriate skill assessments available for use in golf. The aim of this study was to examine the discriminative validity and the test-retest reliability of the newly developed "Nine-Ball Skills Test". Participants of two ability levels (elite, n = 14; high-level amateur, n = 16) each hit nine golf shots of differing combinations of trajectory (straight, fade, draw) and height (normal, high, low) at an individually determined target area. Each shot was scored on its percent error index from the target and whether it achieved the maximum height as required. Participants completed the test twice using a 5-iron club. The elite group scored significantly higher (P < 0.05) than the amateur group for both the first and second rounds of the test as well as the combined scores. The between-round test-retest reliability was deemed to be not acceptable, thus we propose that the test's protocol should include use of the two rounds as standard. Due to the importance of ball striking and flight control to performance in golf, the Nine-Ball Skills Test is appropriate for providing a measure of this skill component in elite and high-level amateur golfers.  相似文献   

3.
In golf, unlike most other sports, individual performance is not the result of direct interactions between players. Instead decision-making and performance is influenced by numerous constraining factors affecting each shot. This study looked at the performance of PGA TOUR golfers in 2011 in terms of stability and variability on a shot-by-shot basis. Stability and variability were assessed using Recurrence Quantification Analysis (RQA) and standard deviation, respectively. About 10% of all shots comprised short stable phases of performance (3.7 ± 1.1 shots per stable phase). Stable phases tended to consist of shots of typical performance, rather than poor or exceptional shots; this finding was consistent for all shot categories. Overall, stability measures were not correlated with tournament performance. Variability across all shots was not related to tournament performance; however, variability in tee shots and short approach shots was higher than for other shot categories. Furthermore, tee shot variability was related to tournament standing: decreased variability was associated with better tournament ranking. The findings in this study showed that PGA TOUR golf performance is chaotic. Further research on amateur golf performance is required to determine whether the structure of amateur golf performance is universal.  相似文献   

4.
Acute whole body vibration training (WBVT) is a tool used amongst coaches to improve performance prior to activity. Its effects on other fitness components, such as balance and stability, along with how different populations respond are less well understood. The aim of the current research is to determine the effect of acute WBVT on balance and stability amongst elite and amateur soccer players. Forty-four healthy male soccer players (22 elite and 22 amateur) were assigned to a treatment or control group. The intervention group then performed 3 × 60 seconds static squat on vibration platform at 40 Hz (±4 mm) with Y balance test (YBT) scores and dynamic postural stability index (DPSI) measured pre and post. DPSI was significantly lower in the elite players in the acute WBVT compared to amateur players (F1, 40= 6.80; P = 0.013). YBT anterior reach distance showed a significant improvement in both amateur and elite players in the acute WBVT group (F1, 40= 32.36; P < 0.001). The improvement in DPSI amongst the elite players indicates a difference in responses to acute high frequency vibration between elite and amateur players during a landing stability task. The results indicate that acute WBVT improves anterior YBT reach distances through a possible improvement in flexibility amongst both elite and amateur players. In conclusion, acute WBVT training appears to improve stability amongst elite soccer players in comparison to amateur players, the exact reasoning behind this difference requires further investigation.  相似文献   

5.
Despite the increasing popularity of futsal, there is little information on performance characteristics of players. We aimed to determine the validity and reliability of a futsal shooting test and to evaluate and compare performance characteristics of three futsal playing levels. Twenty-four males (n = 8 elite, n = 8 semi-elite, n = 8 social) completed two trials to examine the reliability of the Massey Futsal Shooting Test (MFST) and to compare various fitness characteristics between groups. MFST time taken (P = 0.010), shot speed (P < 0.001) and points scored per shot (P < 0.001) were better for elite relative to social players. Test–retest reliability was acceptable for all groups, but it was most repeatable in elite players. Loughborough Soccer Passing Test performance was better in elite relative to social players (P = 0.004). There were no differences in countermovement-jump height between groups. Elite players ran faster over 5 m than both semi-elite (P = 0.043) and social (P = 0.002) and faster than the social players through 10 m (P = 0.028) and 20 m (P = 0.026). Distance covered in the Futsal Intermittent Endurance Test was higher in elite relative to semi-elite (P = 0.005) and social (P < 0.001) groups. The MFST is a valid and reliable protocol to assess futsal shooting-skill performance; elite players have superior shooting and passing skill and have greater sprinting and intermittent-running ability.  相似文献   

6.
The aim of this study was to investigate whether kinematic proximal-to-distal sequencing (PDS) and speed-summation are common characteristics of both partial and full-swing shots in golf players of different skill levels and genders. A total of 45 golfers participated, 11 male tournament professionals, 21 male and 13 female elite amateurs. They performed partial shots with a wedge to targets at three submaximal distances, 40, 55 and 70 m, and full-swing shots with a 5 iron and a driver for maximal distance. Pelvis, upper torso and hand movements were recorded in 3D with an electromagnetic tracking system (Polhemus Liberty) at 240 Hz and the magnitude of the resultant angular velocity vector of each segment was computed. The results showed a significant proximal-to-distal temporal relationship and a concomitant successive increase in maximum (peak) segment angular speed in every shot condition for both genders and levels of expertise. A proximal-to-distal utilization of interaction torques is indicated. Using a common PDS movement strategy in partial and full-swing golf shots appears beneficial from mechanical and control points of view and could serve the purpose of providing both high speed and accuracy.  相似文献   

7.
Abstract

Twenty-four players from the 1st/2nd (elite) and 24 players from the 3rd/4th (non-elite) university football teams were recruited to evaluate the Loughborough Soccer Passing Test (LSPT) and Loughborough Soccer Shooting Test (LSST) as tools to assess soccer skill. The LSPT requires players to complete 16 passes as quickly as possible. The LSST requires players to pass, control, and shoot the ball to targets on a full-sized goal. Participants completed two main trials each separated by at least one day. During both trials, the participants were given practice efforts before recording the mean of the next two (LSPT) or 10 (LSST) attempts as the performance score. For the LSPT, the mean time taken, added penalty time, and overall performance time were less in the elite players (elite: 43.6 s, s = 3.8; non-elite: 52.5 s, s = 7.4; P = 0.0001). For the LSST, there was no difference in the mean points scored per shot between groups (elite: 1.34, s = 0.46; non-elite: 1.28, s = 0.53). However, the elite players had higher mean shot speed (elite: 80 km · h?1, s = 4.5; non-elite: 74 km · h?1, s = 4.2; P < 0.0001) and performed each shot sequence faster (elite: 7.87 s, s = 0.29; non-elite: 8.07 s, s = 0.35; P = 0.037) than the non-elite players. Performance on both tests was more repeatable in elite players. In conclusion, the LSPT and LSST are valid and reliable protocols to assess differences in soccer skill performance.  相似文献   

8.
The purposes of this research were to quantify the kinematics of the lacrosse shot, based on arm dominance and player experience level. Male players (N = 39; 14–30 years; high school [n = 24], collegiate [n = 9], professional [n = 6]), performed overhead shots using dominant and non-dominant sides. Motion was captured using a high-speed, 12-camera optical system and high-speed filming. Body segment rotational velocities and joint angles were determined at key points in the shot cycle from foot contact (0% of shot) to ball release (100% of shot). All players shot with less anterior trunk lean, less transverse shoulder rotation, and slower trunk-shoulder rotational velocities with the non-dominant side than the dominant side (all p < 0.05). Professional players produced crosse angular velocities 21% faster than high school or collegiate players (p < 0.05). Transverse shoulder rotation range of motion on both dominant and non-dominant and trunk rotation sides was highest in the professional players (p < 0.05). These kinematic features enable professional players to produce faster ball speeds than younger players (138 ± 7 km/h vs. 112 ± 15 km/h, respectively; p < 0.05). Less anterior lean or suboptimal rotation sequence could increase proximal shoulder forces that could contribute to injury as in other throwing sports.  相似文献   

9.
Abstract

During practice and competition, golfers are required to use submaximal effort to hit the ball a given distance, i.e., perform a partial shot. While the full golf swing has undergone extensive research, little has addressed partial shots and the biomechanical modifications golfers employ. This study investigates the biomechanical changes between full and partial swings, and determines if the partial swing is a scaled version of the full swing. Using a repeated measures design, 13 male golfers completed a minimum of 10 swings in the full and partial swing conditions, whilst club, ball, kinematic, and kinetic parameters were recorded. Large and statistically significant reductions in body motion (centre of pressure ellipse: 33.0%, p = 0.004, d = 2.26), combined with moderate reductions in lateral shift (25.5%, p = 0.004, d = 0.33) and smaller reductions in trunk rotation (arm to vertical at top of backswing: 14.1%, p = 0.002, d = 2.58) indicate golfers favour larger reductions in proximal measures, combined with diminished reductions as variables moved distally. Furthermore, the partial swing was not found to be a scaled version of the full swing implying a new approach to coaching practices might be considered.  相似文献   

10.
Elite golfers' kinematic sequence in full-swing and partial-swing shots   总被引：1，自引：0，他引：1  
The aim of this study was to investigate whether kinematic proximal-to-distal sequencing (PDS) and speed-summation are common characteristics of both partial and full-swing shots in golf players of different skill levels and genders. A total of 45 golfers participated, 11 male tournament professionals, 21 male and 13 female elite amateurs. They performed partial shots with a wedge to targets at three submaximal distances, 40, 55 and 70 m, and full-swing shots with a 5 iron and a driver for maximal distance. Pelvis, upper torso and hand movements were recorded in 3D with an electromagnetic tracking system (Polhemus Liberty) at 240 Hz and the magnitude of the resultant angular velocity vector of each segment was computed. The results showed a significant proximal-to-distal temporal relationship and a concomitant successive increase in maximum (peak) segment angular speed in every shot condition for both genders and levels of expertise. A proximal-to-distal utilization of interaction torques is indicated. Using a common PDS movement strategy in partial and full-swing golf shots appears beneficial from mechanical and control points of view and could serve the purpose of providing both high speed and accuracy.  相似文献   

11.
In order to maximise the potential for success, developing nations need to produce superior systems to identify and develop talent, which requires comprehensive and up-to-date values on elite players. This study examined the anthropometric and physical characteristics of youth female team handball players (16.07 ± 1.30 years) in non-elite (n = 47), elite (n = 37) and top-elite players (n = 29). Anthropometric profiling included sum of eight skinfolds, body mass, stature, girths, breadths and somatotype. Performance tests included 20 m sprint, counter-movement jump, throwing velocity, repeated shuttle sprint and jump ability test, and Yo-Yo Intermittent Recovery Test Level 1. Youth top-elite players had greater body mass, lean mass, stature, limb girths and breadths than elite and non-elite players, while only stature and flexed arm were higher in elite compared to non-elite players (all P < 0.05). Sum of skinfolds and waist-to-hip ratio were similar between groups (P > 0.05). Top-elite performed better in most performance tests compared to both elite and non-elite players (P < 0.05), although maximal and repeated 10 m sprints were similar between playing standards (P > 0.05). Elite outperformed non-elite players only in throwing velocity. The findings reveal that non-elite players compare unfavourably to top-elite international European players in many anthropometric and performance characteristics, and differ in a few characteristics compared to elite European club team players. This study is useful for emerging team handball nations in improving talent identification processes.  相似文献   

12.
This study identified and compared the full body kinematics of different skill levels in the forehand groundstroke when balls were hit cross court and down the line. Forty-three three-dimensional retro-reflective marker trajectories of six elite and seven high-performance players were recorded using an eight-camera 400 Hz, Vicon motion analysis system. The six highest horizontal velocity forehands with reliable kinematics of all participants were analysed for each specific situation (a total of 156 analysed shots). Significant differences (p < 0.01) and large effect sizes were observed between elite and high-performance players in linear velocity of the shoulder (2.0 vs. 1.2 m/s), angular velocity of the pelvis (295 vs. 168 °/s), and angular velocity of the upper trunk (453 vs. 292 °/s) at impact. The elite group showed a tendency towards higher racquet velocities at impact (p < 0.05). No significant differences were found in angular displacement of the racquet, hip alignment, or shoulder alignment at the completion of the backswing; nor did angular displacement vary significantly at impact. Irrespective of the group, different shoulder, hip, and racquet angles were found at impact, depending on the situation. The results should assist coaches when striving to improve their players' forehand.  相似文献   

13.
Abstract

When using a driver, the centre of pressure of a golfer shows a pattern that is characteristic of one of two distinct swing styles: the “front foot” style or the “reverse” style. The aim of this study was to establish whether these two swing styles are also evident when using other clubs, and if so, to determine whether golfers use the same swing style when using different clubs. Forty-six professional, amateur, and recreational golfers performed swings to hit a ball into a net placed 3 m away. Ten swings were performed for each of the driver, 3-iron, and 7-iron while standing on two force plates. The position of the golfer's centre of pressure parallel with the line of shot and relative to the feet was quantified at eight swing events that were identified from 200-Hz video. Cluster analysis confirmed that the front foot and reverse styles were evident in all three clubs, and most of the golfers (96%) used the same swing style for all three clubs. Golfers that used the reverse swing positioned their centre of pressure nearer to their toes at ball contact compared with golfers that used the front foot swing.  相似文献   

14.
Reliability and validity of two tests of soccer skill   总被引：3，自引：3，他引：0  
Twenty-four players from the 1st/2nd (elite) and 24 players from the 3rd/4th (non-elite) university football teams were recruited to evaluate the Loughborough Soccer Passing Test (LSPT) and Loughborough Soccer Shooting Test (LSST) as tools to assess soccer skill. The LSPT requires players to complete 16 passes as quickly as possible. The LSST requires players to pass, control, and shoot the ball to targets on a full-sized goal. Participants completed two main trials each separated by at least one day. During both trials, the participants were given practice efforts before recording the mean of the next two (LSPT) or 10 (LSST) attempts as the performance score. For the LSPT, the mean time taken, added penalty time, and overall performance time were less in the elite players (elite: 43.6 s, s = 3.8; non-elite: 52.5 s, s= 7.4; P= 0.0001). For the LSST, there was no difference in the mean points scored per shot between groups (elite: 1.34, s = 0.46; non-elite: 1.28, s = 0.53). However, the elite players had higher mean shot speed (elite: 80 km h(-1), s = 4.5; non-elite: 74 km h(-1), s = 4.2; P < 0.0001) and performed each shot sequence faster (elite: 7.87 s, s= 0.29; non-elite: 8.07 s, s= 0.35; P= 0.037) than the non-elite players. Performance on both tests was more repeatable in elite players. In conclusion, the LSPT and LSST are valid and reliable protocols to assess differences in soccer skill performance.  相似文献   

15.
There is limited research studying fluid and electrolyte balance in rugby union players, and a paucity of information regarding the test–retest reliability. This study describes the fluid balance of elite rugby union players across multiple squads and the reliability of fluid balance measures between two equivalent training sessions. Sixty-one elite rugby players completed a single fluid balance testing session during a game simulation training session. A subsample of 21 players completed a second fluid balance testing session during an equivalent training session. Players were weighed in minimal clothing before and after each training session. Each player was provided with their own drinks which were weighed before and after each training session. More players gained body weight (9 (14.8%)) during training than lost greater than 2% of their initial body mass (1 (1.6%)). Pre-training body mass and rate of fluid loss were significantly associated (r?=?0.318, p?=?.013). There was a significant correlation between rate of fluid loss in sessions 1 (1.74?±?0.32?L?h?1) and 2 (1.10?±?0.31?L.?h?1), (r?=?0.470, p?=?.032). This could be useful for nutritionists working with rugby squads to identify players with high sweat losses.  相似文献   

16.
Abstract

The main aim of this study was to identify and compare ball speed and hitting accuracy of forehand and backhand groundstrokes between ATP professionals (elite) and high-performance youth players when shots were played cross-court and down the line to a target square. Six elite and seven high-performance tennis players volunteered to participate in the study. A Doppler-radar device and a digital video camera, operating at 120 frames per second, were used to measure ball speed and accuracy of forehand and backhand groundstrokes in the respective situation (cross-court and down the line). The results of 1040 measured groundstrokes indicate that the ball speed of the forehand and the backhand ground stroke was higher in the elite group when analysing (1) all valid shots, (2) the six fastest shots, and (3) the six most accurate shots (all P < 0.05). In addition, all players achieved a higher forehand speed compared with their backhand when balls were directed cross-court (P < 0.01). The participants demonstrated similar ability when considering accuracy of their groundstrokes (P > 0.05). However, a group difference for accuracy was identified when considering the six fastest forehand shots (P<0.05), and the forehand cross-court stroke was played more accurately than the backhand cross-court stroke by both groups (valid shots and six most accurate shots, P<0.05). Moreover, there was no evidence that players who impacted the ball faster were any less accurate than those who impacted the ball more slowly. Analyses for participants actually revealed a negative correlation between ball speed and mean radial error (accuracy) for the backhand down the line (r= ? 0.77, P<0.01). According to the results of this study, ball speed seems to be the determining factor that separates elite from sub-elite tennis players.  相似文献   

17.
The purpose of this study was to compare kinetic, kinematic, and performance variables associated with full and shortened modern backswings in a skilled group of modern swing (one-plane) golfers. Shortening the modern golf backswing is proposed to reduce vertebral spine stress, but supporting evidence is lacking and performance implications are unknown. Thirteen male golfers performed ten swings of each swing type using their own 7-iron club. Biomechanical-dependent variables included the X-Factor kinematic data and spine kinetics. Performance-related dependent variables included club head velocity (CHV), shot distance, and accuracy (distance from the target line). Data were analysed with repeated measures ANOVA with an a priori alpha of 0.05 (SPSS 22.0, IBM, Armonk, NY, USA). We found significant reductions for the X-Factor (p < 0.05) between the full and shortened swings. The shortened swing condition ameliorated vertebral compression force from 7.6 ± 1.4 to 7.0 ± 1.7 N (normalised to body weight, p = 0.01) and significantly reduced CHV (p < 0.05) by ~2 m/s with concomitant shot distance diminution by ~10 m (p < 0.05). Further research is necessary to examine the applicability of a shortened swing for golfers with low back pain.  相似文献   

18.
ABSTRACT

This study determined the physical and technical demands of elite wheelchair tennis (WT) match-play, how the demands differed between divisions (Men, Women, Quad) and the effect that set result and score margin had on these demands. Seventeen WT players were monitored during a singles competition. Physical measures of performance were analysed using an indoor tracking system and inertial measurement units. Technical measures of performance were examined using video analysis. Physical measures of performance differed by division (Men > Women > Quad) for most parameters. Rallies were longer during Men’s (P = 0.027) and Women’s (P = 0.004) matches compared to Quad’s and fewer shots were hit off 2 bounces in Men’s matches compared to Women’s and Quad’s (P ≤ 0.026). High-speed activity (HSA) increased during losing sets (P = 0.043). Most physical measures of performance increased by moderate to large effects during sets with a small score margin (≤3 games differential). Mean speed and HSA were similar during losing sets, regardless of margin, but decreased (large effects) when winning by a large margin. This study demonstrated the physical and technical demands that elite WT players need to be prepared for and how situational factors can influence these demands.  相似文献   

19.
This study compared the athletic movement skill between elite Under-18 (U18) Australian football (AF) and senior Australian Football League (AFL) players. The U18 sample (n = 13; 17.7 ± 0.6 years) were representatives of an elite talent development programme. The AFL players were classified accordingly; Group 1 (1–4 AFL seasons; n = 20; 21.2 ± 1.9 years) and Group 2 (>5 AFL seasons; n = 14; 26.3 ± 2.6 years). Participants performed an athletic movement skill assessment, inclusive of five foundational movements. Each movement was scored across three assessment points using a three-point scale. Total score for each movement (maximum of nine) and overall score (maximum of 63) were used as criteria. Multivariate analysis of variance (MANOVA) was used to test the effect of developmental group (three levels) on the criteria. Receiver operating curves were built to examine the discriminant capability of the overall score. A significant effect of developmental group was noted, with the U18 sample having a lower mean total score for four of the five movements. Overall scores of 49/63 and 50/63 discriminated the elite U18 sample from Group 1 and Group 2, respectively. U18 players may have less developed athletic movement skills when compared to their senior AFL counterparts.  相似文献   

20.
The transition phase of a golf swing is considered to be a decisive instant required for a powerful swing. However, at the same time, the low back torsional loads during this phase can have a considerable effect on golf-related low back pain (LBP). Previous efforts to quantify the transition phase were hampered by problems with accuracy due to methodological limitations. In this study, vector-coding technique (VCT) method was proposed as a comprehensive methodology to quantify the precise transition phase and examine low back torsional load. Towards this end, transition phases were assessed using three different methods (VCT, lead hand speed and X-factor stretch) and compared; then, low back torsional load during the transition phase was examined. As a result, the importance of accurate transition phase quantification has been documented. The largest torsional loads were observed in healthy professional golfers (10.23 ± 1.69 N · kg?1), followed by professional golfers with a history of LBP (7.93 ± 1.79 N · kg?1), healthy amateur golfers (1.79 ± 1.05 N · kg?1) and amateur golfers with a history of LBP (0.99 ± 0.87 N · kg?1), which order was equal to that of the transition phase magnitudes of each group. These results indicate the relationship between the transition phase and LBP history and the dependency of the torsional load magnitude on the transition phase.  相似文献   

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