RESUMEN
Rugby league has a relatively high injury risk, with the tackle having the greatest injury propensity. The number of tackles players engage in, prior to injurious tackles may influence injury risk, which has yet to be investigated. Therefore, this study investigated if rugby league players are involved in more tackles (as either tackler or ball carrier) (i) in the 10 minutes, or (ii) 1-min periods prior to an injurious tackle-event, (iii) differences for ball carriers vs. tacklers, and (iv) forwards vs. backs. Video analysis was utilised to quantify the number and rate of tackles in the 10-min periods prior to 61 tackle-related injuries. One thousand two hundred and eighty 10-min periods where players were not injured, were used as matched-controls. Generalized mixed linear models were used to analyse mean total and rate for tackles. Injured players were involved in significantly fewer tackles during the 10-min period, yet significantly more tackles during the final minute prior to the injurious tackle-event, compared to non-injured players. There were no differences between ball carriers vs. tacklers during the 10-min period. Both injured position groups were involved in significantly more tackles in the final minute. Additional match data sources are needed to further inform injury preventive strategies of tackle events.
Asunto(s)
Traumatismos en Atletas , Fútbol Americano , Humanos , Fútbol Americano/lesiones , Rugby , Traumatismos en Atletas/epidemiología , Traumatismos en Atletas/etiología , Traumatismos en Atletas/prevención & controlRESUMEN
The Lawn Tennis Association's mini tennis (MT) is a modified version of tennis consisting of progressive stages; however, there have been few attempts to evaluate how MT might shape performance behaviours. Here, we examine effects of playing MT on the emergence of children's match-play behaviours in 48 junior tennis players. Performance in 1010 match-play points were filmed and coded across 4 tennis stages (MT Red, MT Orange, MT Green and Full Ball), using a notational analysis system. Recorded performance variables included rally length, first serve percentage and shot type, for the purpose of analysing inter-stage comparisons. Results showed a series of specific adaptations to playing characteristics across the stages, including rally length, shot variety and serve success. MT Red rallies (7.36 ± 6.06) were longer than Full Ball rallies (3.83 ± 2.40), and a higher percentage of forehands were played at MT Red (66.40 ± 8.49%) than at Full Ball stage (45.96 ± 6.47%). Findings suggested that MT stages can afford children more opportunities to develop their skills and elicit different match-play characteristics than Full Ball task constraints. Coaches, therefore, should consider the nature of emergent adaptations when designing practice environments to facilitate learning in young tennis players.
Asunto(s)
Rendimiento Atlético , Conducta Competitiva , Tenis , Adolescente , Niño , Femenino , Humanos , Aprendizaje , MasculinoRESUMEN
Manipulating task constraints by scaling key features like space and equipment is considered an effective method for enhancing performance development and refining movement patterns in sport. Despite this, it is currently unclear whether scaled manipulation of task constraints would impact emergent movement behaviours in young children, affording learners opportunities to develop relevant skills. Here, we sought to investigate how scaling task constraints during 8â¯weeks of mini tennis training shaped backhand stroke development. Two groups, control (nâ¯=â¯8, ageâ¯=â¯7.2⯱â¯0.6â¯years) and experimental (nâ¯=â¯8, age 7.4⯱â¯0.4â¯years), underwent practice using constraints-based manipulations, with a specific field of affordances designed for backhand strokes as the experimental treatment. To evaluate intervention effects, pre- and post-test match-play characteristics (e.g. forehand and backhand percentage strokes) and measures from a tennis-specific skills test (e.g. forehand and backhand technical proficiency), were evaluated. Post intervention, the experimental group performed a greater percentage of backhand strokes out of total number of shots played (46.7⯱â¯3.3%). There was also a significantly greater percentage of backhand winners out of total backhand strokes observed (5.5⯱â¯3.0%), compared to the control group during match-play (backhandsâ¯=â¯22.4⯱â¯6.5%; backhand winnersâ¯=â¯1.0⯱â¯3.6%). The experimental group also demonstrated improvements in forehand and backhand technical proficiency and the ability to maintain a rally with a coach, compared to the control group. In conclusion, scaled manipulations implemented here elicited more functional performance behaviours than standard Mini Tennis Red constraints. Results suggested how human movement scientists may scale task constraint manipulations to augment young athletes' performance development.
Asunto(s)
Rendimiento Atlético/fisiología , Educación y Entrenamiento Físico/métodos , Deportes de Raqueta/fisiología , Niño , Femenino , Humanos , Aprendizaje/fisiología , Masculino , Destreza Motora/fisiología , Movimiento/fisiología , Tenis/fisiologíaRESUMEN
OBJECTIVES: Conduct a comprehensive epidemiological study of match injury characteristics (incidence, severity, causes, diagnostics, and temporal trends) in professional rugby league. DESIGN: Prospective cohort design. METHODS: Data was captured over the 2013, '14, and '15 seasons, collected via an online-reporting survey tool, and underpinned by nominal group technique-agreed definitions. Injury details were provided by club medical staff in accordance to the survey fields from all European Super League teams (e.g. injury occurrence/return dates, diagnosis, mechanism, recurrence). All time-loss injuries have been reported. RESULTS: Injury incidence of 57 injuries/1000h has been observed over the three-year period, with an average of 34days missed per injury. The final 20-min period was the most significant period for injury occurrence, and higher incidence of injury/1000h played was during the start of the season in February, although an absolute injury risk for injury frequency was shown in April due to the greatest playing time. Forward positions reported the highest injury incidence whilst tackle activities were the most frequent mechanism of injury. Concussions and hamstring strains (5 injuries/1000h) were the most commonly diagnosed injuries, although the knee joint region (10 injuries/1000h) was the most frequently injured area. CONCLUSIONS: In light of the most common injury diagnoses, mechanisms, identified seasonal risk, and time of match, the data should look to inform player preparation in terms of physical conditioning and tackle technique in order to optimise player welfare and availability for participation.