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1.
In this study, we examined the relationship between anthropometric, strength and power characteristics of rugby forwards, their body position when scrummaging, and their ability to apply force when scrummaging. Force applied to an instrumented scrum machine was measured for 56 players, both individually and as scrum packs. Measurements of body position for individuals were made by digitizing videotape records of the trials. Forty players subsequently had their anthropometry assessed and completed several strength and power tests. Body mass, each component of somatotype, maximal anaerobic power developed on a cycle ergometer, and isokinetic knee extension strength correlated significantly with individual scrummaging force. A regression model (P?0.001) including body mass, mesomorphy, maximal anaerobic power and hip angle while in the scrummaging position accounted for 45% of the variance in individual scrummaging force. The packs that produced the largest scrummaging forces were, in general, characterized by a greater pack force to sum of individual force ratio than the packs producing lower forces. Our results emphasize the need for a scrum pack to develop technique and coordination as a unit to maximize scrummaging force.  相似文献   

2.
In this study, we examined the relationship between anthropometric, strength and power characteristics of rugby forwards, their body position when scrummaging, and their ability to apply force when scrummaging. Force applied to an instrumented scrum machine was measured for 56 players, both individually and as scrum packs. Measurements of body position for individuals were made by digitizing videotape records of the trials. Forty players subsequently had their anthropometry assessed and completed several strength and power tests. Body mass, each component of somatotype, maximal anaerobic power developed on a cycle ergometer, and isokinetic knee extension strength correlated significantly with individual scrummaging force. A regression model (P < 0.001) including body mass, mesomorphy, maximal anaerobic power and hip angle while in the scrummaging position accounted for 45% of the variance in individual scrummaging force. The packs that produced the largest scrummaging forces were, in general, characterized by a greater pack force to sum of individual force ratio than the packs producing lower forces. Our results emphasize the need for a scrum pack to develop technique and coordination as a unit to maximize scrummaging force.  相似文献   

3.
Scrummaging is a major component of Rugby Union gameplay. Successful scrummaging is dependent on the coordination of the forward players and the strength of the eight individuals. The study aim was to determine whether individual scrummaging kinetics and other candidate factors associated with scrummaging performance discriminate team scrum performances. Sixteen club-level forwards (stature: 1.80?±?0.1?m; mass: 99.0?±?18.2?kg) were initially divided into two scrummaging packs. A total of 10 various scrum permutations were tested, where players were randomly swapped between the two packs. Winning scrums were determined by two observers on opposite sides of the scrum. Fatigue (100?mm visual analogue scale (VAS)) and scrummaging effort (6–20 rating of perceived exertion (RPE)) were assessed following each scrum contest. Individual scrummaging kinetics were acquired through an instrumented scrum ergometer and muscular power indicated through vertical jump heights. Student’s t-tests were used to differentiate between winning and losing scrum packs. VAS and RPE were assessed using repeated measures ANOVAs. Winning scrum packs had significantly larger combined force magnitudes (p?<?.002), regardless of the player contribution calculations. Additionally, winning packs had less individual movement (p?=?.033) and higher combined vertical jump heights (p?<?.001) but were not significantly heavier (p?=?.759) than losing scrum packs. While perceived VAS and RPE values progressively increased (p?<?.001), no differences in the individual scrum magnitudes were observed between the 1st and 10th scrum (p?=?.418). The results indicated that the combination of individual forces, variation in movement and factors related to scrummaging performance, such as vertical jump height, were associated with team scrummaging success.  相似文献   

4.
Two rugby union forward packs of differing ability levels were examined during scrummaging against an instrumented scrum machine. By systematically moving the front‐row of the scrum along the scrum machine, kinetic data on each front‐row forward could be obtained under all test conditions. Each forward pack was tested under the following scrummaging combinations: front‐row only; front‐row plus second‐row; full scrum minus side‐row, and full scrum. Data obtained from each scrum included the three orthogonal components of force at engagement and the sustained force applied by each front‐row player. An estimate of sub‐unit contributions was made by subtracting the total forward force on all three front‐row players from the total for the complete scrum. Results indicated the primary role of the second‐row appeared to be application of forward force. The back‐row ('number eight') forward did not substantially contribute any additional forward force, and added only slightly to the lateral and vertical shear force experienced by the front‐row. The side‐row contributed an additional 20–27% to the forward force, but at the expense of increased vertical forces on all front‐row forwards. Results of this investigation are discussed in relation to rule modification, rule interpretation and coaching.  相似文献   

5.
In today’s leading football training centres, state-of-the-art performance diagnostic systems such as the “Footbonaut” allow controlled and standardized assessments of physical and mental components of agility, e.g. speed of action and ball control, that are considered to be decisive for talent identification and development. However, effects of induced physical and mental strain on performing football-specific practice patterns remain to be elucidated, particularly in youth players, and, thus, characterize the purpose of this study. 33 randomly assigned competitive football players (U14 to U16) performed a standardized Footbonaut practice pattern (i.e. 20 balls randomly drawn at 50?km/h each), prior to and immediately after either mentally demanding tasks (MDT; n?=?11; continuous Vienna Test System’s Stroop task and determination test), physically demanding tasks (PDT; n?=?11; consisted of 4?×?4?min of football-specific high-intensity intervals with 3?min of active recovery in between) or a control condition (CON; n?=?11). Continuous heart rates (HR) as well as self-perceptions of fatigue were assessed. Main findings revealed performances for speed of action (p?=?0.44; f?=?0.01) and ball control (p?=?0.15; f?=?0.03) that were not modulated in the face of induced physical and mental strain as indicated by increased HR following PDT (p?<?0.001; d?>?0.8), or in the face of increased self-perceptions of fatigue following PDT and MDT (both p?<?0.001; both d?>?0.8) compared to CON. This is in line with a suggested talent factor and previous reports on motivational trade-off aspects in youth players. However, the present study’s short-timed practice patterns make it difficult to reliably compare a measuring sensitivity to complex football-specific movement behavioural and technical proficiencies with respect to mental and physical strain of longer-lasting football games and, thus, need further investigation in favour of improving talent identification and development using the Footbonaut.  相似文献   

6.
Demands for female handball players are not yet sufficiently specified, especially not with respect to position-specific performance. For optimal match preparation, individual training based on specific demands of each position is necessary. Consequently, the aim of the study was to gain insight into position-specific differences in female handball players in order to establish position-specific training recommendations. Data from 652 female players from German leagues of all levels were analyzed using a test-battery assessing handball-relevant physical performance factors. Players were tested during their usual training in their regular training locations for running, throwing speed, jumping height, reaction-speed, basic running endurance, arm and abdominal muscle strength and hamstrings and lower back flexibility. Significant differences between positions were found for several parameters, while the differences were pronounced variably at the different performance levels. For example, goalkeepers performed worst in the Half-Cooper test (p?<?0.001) at elite level with wings displaying the best values. Halfbacks had the highest throwing speed (p?<?0.001) and jumping heights (p?<?0.002) at elite level. Goalkeepers were slowest for best and mean value out of five attempts (p?<?0.001; p?<?0.010) in 20?m sprint but, together with wings outperformed half and centre backs at elite level in 30?m sprint (best out of two attempts, p?<?0.001). Goalkeepers also did fewer chin ups than wing and back players at elite level (p?<?0.003). The present study demonstrated positional differences regarding physical performance parameters, thus suggesting the need to intensify position-specific training, especially for goalkeepers during preparation and in-season. Also, position-specific testing during selection-processes might be indicated.  相似文献   

7.
In Paralympic seated throwing events, the athlete can throw with and without an assistive pole. This study aimed to identify and compare performance-related kinematic variables associated with both seated throwing techniques. Twenty-nine non-disabled males (21.9 ± 2.6 years) performed 12 maximal throws using a 1-kg ball in two conditions (no-pole and pole). Automatic 3D-kinematic tracking (150 Hz) and temporal data were acquired. There was no significant difference between ball speeds at the point of release between conditions (no-pole = 12.8 ± 1.6 m/s vs. pole = 12.9 ± 1.5 m/s). There were four kinematic variables that were strongly correlated with ball speed when throwing with or without an assistive pole. These variables were elbow flexion at the start phase (pole r = .39 and no-pole r = .41), maximum shoulder external rotation angular velocity during the arm cocking phase (pole r = .42), maximum shoulder internal rotation angular velocity during the arm acceleration phase (pole r = .47), and should internal rotation angular velocity at the instant of ball release (pole r = .40). The pole clearly influenced the throwing technique with all four strongly correlated variables identified in this condition, compared to only one during the no-pole condition. When using the pole, participants produced significantly higher shoulder internal rotation angular velocities during the arm acceleration phase (pole = 367 ± 183°/s vs. no-pole = 275 ± 178°/s, p < .05) and at the instant of ball release (pole = 355 ± 115°/s vs. no-pole = 264 ± 120°/s, p < .05), compared to throwing without the pole. These findings have implications for the development of evidence-based classification systems in Paralympic seated throwing, and facilitate research that investigates the impact of impairment on seated throwing performance.  相似文献   

8.
This study aimed to compare the effects of synchronous (SYN) vs asynchronous (ASY) modes of wheelchair propulsion in field sprint tests on performance and biomechanical parameters. Seven elite wheelchair basketball players performed two separate (SYN and ASY) straight-line 20-m sprints. ASY increased sprint time and decreased push frequency compared to SYN (p < 0.05). Peak velocity and total force for the mean of the last three pushes were higher in SYN. Rate of rise was higher in SYN for the first, second and third pushes (p < 0.05). No significant difference was found for peak power and mean work. SYN mode induces better performance (13% difference in speed). However, the increase in rate of rise, thus the expansion of the total force when gripping the hand rim, push frequency and total force in SYN modes seems to expand the risk of developing musculoskeletal disorders during manual wheelchair propulsion for upper limb joints than ASY.  相似文献   

9.
Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost.  相似文献   

10.
The aim of this study was to compare cervical spine kinematics in rugby union front row players during machine-based and “live” scrummaging. Cervical spine kinematics was measured via electromagnetic tracking of sensors attached to the head and thorax. Joint angles were extracted from each trial at two time points (“bind” prior to engagement and instant of impact) for comparison between scrummaging conditions. The effect of scrummaging condition on kinematics was evaluated using a mixed effects model and estimations were based on a Bayesian framework. With differences ranging from 38° to 50°, the results show that the cervical spine is consistently more flexed when scrummaging against opponents than against a scrum machine. In contrast, there are little differences in the excursion of lateral-flexion (range 5–8°) and axial rotation (7°) between the two conditions. The findings from this study provide clear information on motion patterns in different scrum formations, and suggest that the current design of scrum machines may not promote the same pattern of movement that occurs in live scrums. The results highlight that findings from previous studies that have investigated kinematics during machine-based scrummaging may not be generalisable to a competitive scrummaging context.  相似文献   

11.
Two rugby union forward packs of differing ability levels were examined during scrummaging against an instrumented scrum machine. By systematically moving the front-row of the scrum along the scrum machine, kinetic data on each front-row forward could be obtained under all test conditions. Each forward pack was tested under the following scrummaging combinations: front-row only; front-row plus second-row; full scrum minus side-row, and full scrum. Data obtained from each scrum included the three orthogonal components of force at engagement and the sustained force applied by each front-row player. An estimate of sub-unit contributions was made by subtracting the total forward force on all three front-row players from the total for the complete scrum. Results indicated the primary role of the second-row appeared to be application of forward force. The back-row ('number eight') forward did not substantially contribute any additional forward force, and added only slightly to the lateral and vertical shear force experienced by the front-row. The side-row contributed an additional 20-27% to the forward force, but at the expense of increased vertical forces on all front-row forwards. Results of this investigation are discussed in relation to rule modification, rule interpretation and coaching.  相似文献   

12.
The Functional Movement Screen (FMS) has been applied to identify predisposed players, mainly in professional sports, and their injury risk. Empirical evidence on the FMS in amateur soccer is scant. Furthermore, the composite FMS score contains upper, lower, and core-related body items, which might be related differently in soccer-specific injury incidences. The aim of this study was twofold: to investigate the relationship between the composite FMS score and the injury incidence of amateur soccer players and to analyze the contribution of single FMS test items to the injury state. In all, 83 amateur male soccer players (23?±?4 years old) were evaluated using the FMS prior to the preparation period of the 2016/2017 season. Injuries (lower extremities, non-contact, time loss) were continuously documented throughout the first competition period. The composite FMS score differed significantly (p?=?0.017) between injured (15.1?±?2.5) and non-injured (16.5?±?2) players. A twofold increase in the risk of injury was found for a composite FMS score of 14 or less. Significant correlations between single test items with a score?≤?2 and injured players were found for the trunk stability push-up exercise (χ2?=?17.4, df?=?1, p?<?0.001, φ?=?0.5) and the rotary stability exercise (χ2?=?6.7, df?=?1, p?=?0.009, φ?=?0.3). The composite FMS score seems to be an indicator of injury risk in amateur soccer with injured players having lower core stability and lower core strength.  相似文献   

13.

Background and aim

This study examined the effects of a 6-week high-intensity interval training (HIIT) vs. low-intensity endurance training (LOW), applied during physical education on motor performance, mood and perceived exertion.

Methods

Over a period of 6 weeks, 85 pupils (34 male; 51 female; age: 11.9?±?0.9 years) performed 11 sessions of either HIIT (20?min, intervals from 10?s to 4?min at about 90–100% of average running speed of 6?min run [vmean]) or LOW (30?min, intervals from 6–25?min at about 65–85% vmean). Before and after the 6?week intervention each pupils’ anthropometry and motor performance (20?m sprint, standing long-jump, lateral jumping from side to side, push-ups, sit-ups, 6?min run) were assessed. Session rating of perceived exertion (RPE) was recorded after each session and mood was assessed by questionnaire following the 3rd, 6th, 9th and 11th session.

Results

RPE (p?<?0.05) was higher and mood more positive (p?<?0.05) with HIIT compared to LOW. Performances in the 6?min run (p?<?0.001; part. η2?=?0.473), 20?m sprint (p?<?0.001; part. η2?=?0.226), standing long-jump (p?<?0.05; part. η2?=?0.056), push-ups (p?<?0.001; part. η2?=?0.523) and sit-ups (p?<?0.001; part. η2?=?0.146) improved following HIIT and LOW with no significant time?×?group interaction (except for the sit-ups [p?<?0.05; part. η2?=?0.048]).

Conclusions

HIIT and LOW improved the performances in 6?min run, 20?m sprint, standing long-jump and push-ups similarly. However, the improvements in HIIT compared to LOW were achieved in 30% less time. As time is limited in physical education classes, HIIT offers a new perspective for improving endurance and motor performance in children. The positive mood associated with HIIT demonstrates the applicability in physical education.
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14.
An assessment of attitudes toward language awareness in physical education classes offers the possibility to evaluate learning and teaching opportunities related to this topic offered at universities. However, valid research instruments for this undertaking are currently lacking. The present article reports on the development and validation of a questionnaire for assessing attitudes toward language awareness in sports classes (“Erfassung von Einstellungen zur Sprachbildung im Sportunterricht,” ESBiS). A validation study of the ESBiS included N?=?254 student physical education teachers, 37.8% female, mean age 22.16 years, standard deviation 2.74 years. Explorative factor analysis identified a five-factor structure with the ESBiS factors linguistic goal and performance transparency, promotion of writing, language-corrective feedback, use of scaffolding, and advancement of technical vocabulary. The analyses indicate good factorial validity and reliability of the individual scales. The ESBiS factors can be satisfactorily modelled using confirmatory factor analyses. The ESBiS instrument thus demonstrates good psychometric quality. Furthermore, in some instances, very low positive correlations of the ESBiS factors with the validation criterion of multicultural attitudes could be shown. Additionally, correlation analyses with individual characteristics of the student physical education teachers showed that the developed instrument has sensitivity and discriminatory ability.  相似文献   

15.
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16.
Compared to sports performers, relatively little is known about how sports officials make decisions at a perceptual-cognitive level. Thus, this study examined the decision-making accuracy and gaze behaviour of rugby union referees of varying skill levels while reviewing scrum scenarios. Elite (n = 9) and trainee (n = 9) referees, as well as experienced players (n = 9), made decisions while watching ten projected scrum clips and wearing a mobile eye-tracker. Decision-making accuracy and gaze behaviour were recorded for each scrum. The elite and trainee referees made more accurate decisions than the players, and differences in gaze behavior were observed. The elite and trainee referees displayed lower search rates, spent more time fixating central-pack (i.e., front rows, binds, and contact point) and less time fixating outer-pack (e.g., second rows) and non-pack (e.g., other) locations, and exhibited lower entropy than the players. While search rate failed to predict decision-making accuracy, the time spent fixating central-, outer-, and non-pack locations, as well as entropy, were significant predictors. The findings have implications for training perceptual-cognitive skill among sports officials.  相似文献   

17.
Abstract

There are several ways of carrying the ball in rugby union, which could influence the speed at which a player can run. We assessed 52 rugby players (34 males, 18 females) during a maximum sprint over 30 m without the ball, with the ball under one arm, and with the ball in both hands. Timing gates were used to measure time over the initial 10 m and the last 20 m. It has previously been reported (Grant et al., 2003 Grant, S. J., Oommen, G., McColl, G., Taylor, J., Watkins, L.Friel, N. 2003. The effects of ball carrying method on sprint speed in rugby union football players. Journal of Sports Sciences, 21: 1009–1015. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) that running with the ball produces a slower sprinting speed than running without the ball. We hypothesized that the decrease in speed caused by carrying the ball would become less marked with the experience of the player. The male and female players were each divided into two groups: a “beginner” group that consisted of players in their first or second season and an “experienced” group that was composed of players who had played for more than two seasons. A 2 × 3 mixed-model analysis of variance was used to identify differences (P < 0.01) between the beginner and experienced groups in the three sprinting conditions. The times for the males for the first 10 m sprints without the ball, with the ball under one arm, and with the ball in both hands were 1.87 ± 0.08 s, 1.87 ± 0.08 s, and 1.91 ± 0.1 s for the beginners, and 1.87 ± 0.1, 1.88 ± 0.1 and 1.88 ± 0.12 for the more experienced players respectively. The times for the females for the first 10 m without the ball, with the ball under one arm, and with the ball in both hands were 2.13 ± 0.16 s, 2.19 ± 0.17 s, and 2.20 ± 0.16 s for the beginners, and 2.03 ± 0.12 s, 2.03 ± 0.09 s, and 2.04 ± 0.1 s for the more experienced players respectively. For the last 20 m of the 30-m sprint, there were differences between the different sprint conditions (P < 0.001) but no differences that were attributable to experience (P = 0.297). The times for the males over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 2.58 ± 0.19 s, 2.61 ± 0.12 s, and 2.65 ± 0.12 s for the beginners, and 2.59 ± 0.12, 2.62 ± 0.23, and 2.65 ± 0.18 s for the more experienced players respectively. The times for the females over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 3.25 ± 0.38 s, 3.35 ± 0.42 s, and 3.40 ± 0.46 s for the beginners, and 3.04 ± 0.32 s, 3.06 ± 0.22 s, and 3.13 ± 0.27 s for the more experienced players respectively. No gender-specific differences were detected. The results of this study suggest that practising sprints while carrying a ball benefits the early phase of sprinting while carrying the ball.  相似文献   

18.
In the context of strength training in rehabilitation, visual movement control can be helpful to ensure correct movements. However, there are only a few studies that deal with the effectiveness of feedback during resistance exercises. To investigate the effect of feedback during guided exercise, 18 young adults (28.8?±?5.5 years) and 12 senior citizens (67.9?±?4.1 years) were tested. Subjects performed shoulder press exercises (3 sets, 15 repetitions) with and without visual movement control in a randomized order. On day 1, the subjects trained without load, and on day 2 they trained at 50% of their single repetition maximum. Joint articulation at the elbow was recorded using elbow extension and flexion. Autocorrelation was used to determine the reproducibility of movements. Subjects achieved better reproducibility of the movement with feedback than without (χ2?=?19.73; p?<?0.001). There was no effect of the load on motion accuracy (p?>?0.05), but the age group showed a significant effect (χ2?=?6.00; p?=?0.014). The younger group shows a higher degree of movement accuracy. In summary, visual movement control is useful in guided exercises to control movement execution. In clinical setting, this may be a way to control the motion performance of guided strength exercises and to ensure purposeful muscle work. Further studies should clarify the effect of visual feedback on the movement quality in unguided strength exercises.  相似文献   

19.
The purpose of this pilot study was to investigate the effect of playing-position-dependent training routines in soccer on the various muscle–tendon parameters. We hypothesized that there would be differences in such parameters between competitive goalkeepers and midfielders. According to their playing position, 21 healthy volunteers were assigned to goalkeeper (n?=?7), midfielder (n?=?7), and control (n?=?7) groups. To investigate the muscle–tendon parameters, we determined the maximum dorsiflexion range of motion and the corresponding muscle thickness, fascicle length, and pennation angle of the gastrocnemius medialis. Passive resistive torque and maximum voluntary contraction were measured with a dynamometer. Observation of muscle–tendon junction displacement with ultrasound allowed us to determine length changes in the tendon and muscle, respectively, and hence to calculate stiffness. There was no significant difference in range of motion, passive resistive torque, muscle–tendon stiffness, and the examined structural parameters (e.g., tendon stiffness) between the three groups. However, we found a significant difference in maximum voluntary contraction torque between the goalkeepers and midfielders vs. the controls, but not between the athlete groups. Habitual training leads to higher muscle strength in soccer players compared to less active persons. However, soccer training does not lead to specific muscle and tendon architecture adaptations according to playing position or when compared to less active persons.  相似文献   

20.
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