Test-Retest Reliability of Task Performance for Golf Swings of Medium- to High-Handicap Players.

Background: Golf swing performance in medium- to high-handicap players must be reliably measured to use this variable in both research studies and in applied settings. Nevertheless, there are no studies published on this topic and test−retest evidence is only available for low-handicap players. The aim of this study was to determine the number of attempts necessary to obtain a reliable measurement protocol for swing performance variables in medium- to high-handicap players. Methods: Ten amateur players (55.67 (13.64) years, 78.4 (11.4) kg, 1.75 (7.95) m) took part in a test−retest study in two experimental sessions one week apart. In each one, fifteen swings with a six iron and a driver were evaluated with a 3D Doppler tracking golf radar. Results: The results showed that variables related to side carry could not be reliably measured in medium- to high-handicap players in only fifteen trials (ICC < 0.26, SEM > 12.05 m and MDC > 33.41 m). The rest of the performance variables related to the club and ball trajectories could be reliably measured with a 3D Doppler radar with between seven and ten swings. Conclusions: At least seven swings are recommended for the driver and ten for the six iron to measure golf swing performance.

Effects of a notational analysis-based intervention on coaches' verbal behaviour according to physiological activation during competition.

The aim of this study was to examine the effects of a notational analysis-based intervention on coaches' verbal behaviour considering their physiological activation during competition and game actions. Verbal behaviour, physiological activation (heart rate), and game actions of 4 handball coaches were recorded for a total of 28 matches. Each coach was recorded in 7 matches, three pre-interventions, two post-intervention, and two retention. Verbal behaviour was assessed using the Coach Analysis and Intervention System (CAIS: Cushion et al., 2012), and game actions were coded as positive or negative depending on their outcome. In total, 15223 verbal behaviours and 3780 game actions were recorded. The intervention programme sought to help coaches to provide constructive information (corrective feedback and instructions) after negative events or actions, encourage players (especially when the team is losing or playing badly), reduce the protests to the referee, and reduce or eliminate punishment to players. Chi-square analysis suggested that the intervention stimulated the intended changes in coaches' behaviour, and that these changes were retained for subsequent games. Verbal behaviour changed depending on the physiological activation. This study suggests that a brief (two-session) notation-based intervention can elicit changes in coaches' verbal behaviour during competition.

Fitness testing in tennis: Influence of anthropometric characteristics, physical performance, and functional test on serve velocity in professional players.

The aims of this study were to examine the relationship between anthropometric variables, physical performance, and functional test with serve velocity regarding tennis players' level and to design regression models that effectively predict serve velocity. A sample of sixteen male tennis players participated in this study (national level = 8, professional level = 7). Anthropometric measurements (body mass, height, body mass index and body segments) and physical test (hand strength, countermovement jump, jump on serve, and serve velocity) and functional test (medicine ball throw overhead and shot put) were performed. No differences in anthropometrics and physical test were found between national and professional levels. A significant positive correlation (p < 0.05, ranging for 0.603 to 0.932) was found between some anthropometrics measurements (body mass, height, arm, forearm, and leg segments), physical parameters (hand strength, countermovement jump) and functional test (medicine ball throw shot put and overhead) with serve velocity for all tennis players. Multiple regression analysis indicated that medicine ball throw shot put was the most important test to explain serve velocity (r2 = 0.869). The results showed how the combination of physical and anthropometric factors have an impact on serve velocity. In addition, a new functional fitness test (medicine ball throw shot put) is proposed as an alternative to traditional medicine ball throw overhead due to its high reproducibility (inter-trial reliability) and predictive validity values, as well as by multi-segmental coordination movement similar to tennis serve.

Comparison of service tactic formation on players' movements and point outcome between national and beginner level padel.

The aim of this study was to analyze the influence of service tactic formation on players' movements and point outcome at two different performance levels. The sample contained 2,148 points corresponding to 18 matches from two male padel indoor tournaments. Players were classified according to their game level: high-level (N = 36; age = 33.3 ± 6.9 years) and beginner (N = 36; age = 35.4 ± 6.8 years). Variables pertaining to service tactic formation (conventional or Australian), point outcome and movement patterns were analysed from the matches through systematic observation. The results showed how high-level players used a significantly higher percentage of the Australian formation than beginners. Also, high-level players won a significantly higher percentage of points than recreational players when using both service tactics. According to movement variables, servers were significantly closer to the net and the side wall using a conventional formation when the returner hit the ball. Furthermore, servers had to move quicker when they used the Australian formation. Finally, the comparison of movement patterns of servers according to game level, showed how high-level players ran faster to the offensive position, covered a greater distance and spent less time between serve and return impacts than beginners.

Ball Impact Position in Recreational Male Padel Players: Implications for Training and Injury Management.

Racket sports such as padel are characterized by the repetition of unilateral gestures, which can lead to negative adaptations like asymmetries or overuse musculoskeletal injuries. The purpose of this study was to determine the differences in ball impact positions (i.e., forward or backward of the center of gravity) in nine stroke types in a sample of forty-eight recreational male padel players. The sample included 14,478 shots corresponding to 18 matches from six tournaments. Forty-eight male padel players were classified into two groups according to their level: trained (n = 24) and novice (n = 24). Type of stroke and ball impact position were registered using a computerized motion tracking video system. The ball impact position was computed from the distance (cm) between the coordinates of the ball and the player's center of gravity. Results show that trained players hit the ball in a more backward position (from 11 to 25 cm, compared to novice) in serve and offensive strokes (volleys, trays, and smashes) but used more forward strokes (from 7 to 32 cm, compared to novice) in defensive shots (groundstrokes, wall strokes, and lobs). Because the current differential variables are trainable and demonstrated to be of relevance for performance, the findings of this study may assist padel coaches in designing proper training plans to improve effectiveness and to prevent musculoskeletal injuries regarding the type of stroke and ball impact position. Such knowledge may constitute a very important factor affecting technique, biomechanics, and injury management in padel players of different competitive levels.

Stroke Analysis in Padel According to Match Outcome and Game Side on Court.

The aim of this study was to analyze the distribution of padel strokes, their effectiveness, direction, and court zone, comparing between the winning and losing pairs in the match and the playing side of the players. The sample included 8441 strokes corresponding to 1055 points out of a total of nine padel matches in the First National Category. The variables analyzed were type of stroke, court area, effectiveness and directions of the strokes, match outcome, and game side. Matches were analyzed through systematic observation. The results showed that the winning pair made a significantly higher percentage of winners, and cross-court smashes and volleys from the offensive zone. In addition, players on the left side executed a higher percentage of cross-court and winning shots than the players on the right side. Such knowledge may constitute a useful guide in the design of appropriate game strategies and specific training sessions based on the shots that will help players to win the match according to the role of the player and depending on their game side.

Analysis of Performance Parameters of the Smash in Male and Female Professional Padel.

The aim of this study was to analyze the distribution and effectiveness of the different types of smash in professional padel according to the area and direction of the strokes and the gender. Through systematic observation, 1.015 smashes from eight finals (four men's and four women's) of the professional matches were analyzed. The smashes were categorized into four types of smash: tray, flat, topspin and off the wall. The results showed both men's and women's that the tray is the most used smash by padel players, presenting a percentage of point continuity of almost 90%. The flat and topspin smashes are the strokes that achieve the highest percentage of winning points (near 60%), although this efficiency decreases significantly when the players move away from the net area (p < 0.05), especially in the flat smash. Men perform a higher percentage of winning smashes than women, mainly in the flat smash (p = 0.02). Furthermore, with regards to direction, flat and off the wall smashes are predominantly down the line strokes and women perform significantly more cross court topspin smashes than men (p = 0.005). The results shown could be used to design tasks and exercises by padel coaches at professional players.

Differences in kinematic and match-play demands between elite winning and losing wheelchair padel players.

We aimed to compare the match-play and kinematic demands of the translation and rotation movements of elite wheelchair padel players as a function of match results. Twenty-two elite male players were video-analysed with a two-dimensional direct linear transformation (DLT) -corrected video system across seven matches of a professional tournament. Distance, turns, changes of direction, linear and angular speed, acceleration and the players' heart rate (HR) were recorded. Losing couples in wheelchair padel covered greater distances than winners (P <0.001; r = 0.024) and did so at a higher speed (P <0.001; r = 0.06), while making greater efforts by accelerating (P <0.001; ∅ = -0.021), braking (P <0.001; ∅ = -0.014), and remaining less time stationary (P <0.001; ∅ = 0.059). In addition, losers performed more turns per rally (P <0.001; r = 0.04) at a faster speed, greater angular accelerations (P <0.001; V = 0.06) and greater average (P = 0.007; d = 0.91) and maximum (P = 0.20; d = 0.69) HR values. These data suggest that winner couples performed a better court positioning and employed a strategy to move the opponent during rallies in order to avoid them optimally reaching the ball.

The Effect of the Return of Serve on the Server Pair's Movement Parameters and Rally Outcome in Padel Using Cluster Analysis.

Purpose: The pressure exerted on racket sports players by the service has been well documented. Whilst the return of serve has been suggested through qualitative interviews as being of similar importance there is a dearth of quantitative data to support this contention. This study analyzed time, speed, and distance parameters related to the outcome of the return of serve (ROS) in Padel, a sport similar to tennis but played on a court bounded by walls and played in doubles format only. Methods: Matches (n = 18) at two tournaments, sanctioned by the Valencian Federation, in 2012 were recorded and processed using Tracker software. ROS shot type (flat or lob), ball location, players' positions on court and movement parameters between the ROS and the third shot of the server were captured 25 times per second. Results: Both lob and flat ROS produced six main clusters, as well as a small proportion of shots deemed outliers. The clusters differentiated shots played by two different level players (National and Regional), whether the ROS was played following a first or second serve, whether the serving pair adopted a conventional or Australian formation and whether the rally ended in a short number of shots (seven or less) or not. Conclusion: It was suggested that the aim of the ROS in Padel was to prevent the serving pair winning the rally quickly, since the advantage of the serve diminished after around 6 to 8 shots. This was best achieved by good depth on lobs, regardless of the direction, and pace on low shots, predominately aimed toward the server. This approach should be further modified to include the time between serve and ROS and consideration could be given to classifying attacking and defending positions.

Technical, tactical and movement analysis of men's professional tennis on hard courts.

BACKGROUND: There is very little information in tennis relating performance to both the movement of the players and the effectiveness of their shots. This study aimed to identify differences between winners and losers in the volume and intensity of their movements, as well as in the effectiveness of their shots. METHODS: Matches (N.=8) at the 2011 ATP 500 tournament in Valencia (Spain) were recorded and analyzed using SAGIT, a computerized vision-tracking system. Data were split into points for movement analysis, and into games for stroke analysis. RESULTS: Players winning points used more offensive strategies and spent more time in the offensive zone than point losers. They also forced point losers to cover more distance at a higher speed. Game winners hit more winning shots, made fewer unforced errors, and were more effective than game losers. CONCLUSIONS: These results suggest that winner players controlled the game by playing more offensively and forcing losers to play in defensive positions, move greater distances at a faster speed, and make more errors.

Movement characteristics of elite tennis players on hard courts with respect to the direction of ground strokes.

Previous studies of movement characteristics in tennis have considered the effect of playing surface but have assumed that playing strategies are simply determined by the surface as opposed to being under an individual's control. This study considered the selection of cross court or down the line ground strokes as being indicative of playing strategy and measured the outcome of playing these shots in terms of the opponent's movements. Matches (N = 8) at the 2011 ATP tournament 500 Valencia were recorded and analysed using SAGIT, a computer vision tracking system that allowed both players' movements to be tracked automatically, albeit with operator supervision. The data was split into (N = 188) games for analysis purposes and these lasted a median 174.24 seconds with active time (ball in play) a median proportion of 34.89% (IQR = 10.64%) of total time. During the active time losers of games tended to cover less distance (median = 80.17 m), move quicker (median = 1.38 m·s(-1)), spend more time in the defensive zones (median = 14.24 s) and less in the offensive zones (median = 44.74 s). These results suggested that game winners tended to dominate game losers, forcing them to exhibit behaviors typically associated with a defensive strategy. Defensive and offensive strategy are not well defined currently and future investigations should consider movements in relation to individual shots, in particular their velocities, at the rally level and by different individuals to better understand successful performance. Key PointsDuring the active time losers of games covered less distance, moved quicker, spend more time in the defensive zones and less in the offensive zones.These results suggested that game winners tended to dominate game losers, forcing them to exhibit behaviors typically associated with a defensive strategy.There are no differences between the proportion of cross court shots and down the line shots played by game winners and game losers.Future research should consider individual shots at the rally level to better understand successful performance and ultimately strategy.