Are there differences between male and female badminton athletes in sleep, physical activity and sedentary time? / ¿existen diferencias entre atletas de basdminton masculinos y femeninos en el sueño, actividad física y tiempo de sedentarismo? / Existem diferenças entre atletas de badminton masculinos e femininos no sono, atividade física e tempo de sedentarismo?

ABSTRACT Introduction: High-performance athletes often undergo periods of exhaustive training and insufficient recovery, which can lead to decreased performance, but it is not clear whether there are any differences between the sexes in the level of habitual physical activity, sedentary time or sleep quantity and quality in young highly trained badminton athletes. Objectives: The aim of this study was to compare the habitual physical activity (PA), sedentary time and sleep quantity and quality of highly trained young male and female badminton athletes and non-athletes. Methods: Twenty-seven young badminton athletes and twenty-one non-athletes (control group) were recruited. Sleep duration and quality (total time in bed, total sleep time, wake after sleep onset, sleep efficiency and latency), total counts, vigorous activity time and sedentary time were measured using a tri-axial accelerometer. Results: Male athletes spent less sedentary time (p=0.028), more time in vigorous activity (p=0.016) and had higher total counts (p<0.001) than the male control group. There were no significant differences in sedentary time (p=0.702) or vigorous activity time (p=0.205) between the female athletes and non-athletes, but the female athletes accumulated higher total counts than the female control group (p=0.003). There were no significant differences between the sexes or groups for time in bed, total sleep time, sleep efficiency, wake after sleep onset and latency (p> 0.05). Conclusion: Among males but not females, young highly trained badminton athletes had less sedentary time and more time in vigorous activity than the non-athletes, however, there were no significant differences between the sexes or groups in sleep quantity and quality. Level of evidence III; Case-control study .

RESUMEN Introducción: Los atletas de alto rendimiento con frecuencia son sometidos a períodos de entrenamiento exhaustivo y recuperación insuficiente, lo que puede llevar a una disminución del desempeño, pero no está claro si hay diferencia entre los sexos en cuanto al nivel de actividad física habitual, tiempo sedentario, cantidad y calidad del sueño en jóvenes atletas de bádminton altamente entrenados. Objetivos: El objetivo de este estudio fue comparar la actividad física habitual (AF), el tiempo de sedentarismo y la duración y calidad del sueño en jóvenes atletas de bádminton altamente entrenados y de no atletas, del sexo femenino y masculino. Métodos: Fueron reclutados veintisiete jóvenes atletas de bádminton y veintiuno no atletas (grupo control). La duración y la calidad del sueño (tiempo total en la cama, tiempo total de sueño, vigilia después del inicio del sueño, eficiencia y latencia del sueño), counts totales, el tiempo en actividad vigorosa y el tiempo de sedentarismo fueron medidos con un acelerómetro triaxial. Resultados: Los atletas del sexo masculino tuvieron menos tiempo de sedentarismo (p = 0,028), más tiempo de actividad vigorosa (p = 0,016) y mayor cantidad de counts totales (p <0,001) que el grupo control masculino. No hubo diferencias significativas en el tiempo de sedentarismo (p = 0,702) o tiempo de actividad vigorosa (p = 0,205), entre las atletas y no atletas, pero las atletas del sexo femenino acumularon mayor cantidad de counts totales que el grupo control femenino (p = 0,003). No hubo diferencias significativas entre los sexos o grupos para tiempo en la cama, tiempo total de sueño, eficiencia del sueño, vigilia después del inicio del sueño y latencia (p> 0,05). Conclusiones: Entre hombres, pero no entre mujeres, los jóvenes atletas de bádminton altamente entrenados tuvieron menor tiempo de sedentarismo y mayor tiempo en actividades vigorosas que los no atletas; entretanto, no hubo diferencia significativa entre los sexos o grupos en la cantidad y calidad del sueño. Nivel de evidencia III; Estudio de caso control .

RESUMO Introdução: Atletas de alto rendimento com frequência são submetidos a períodos de treinamento exaustivo e recuperação insuficiente, o que pode levar à diminuição do desempenho, mas não está claro se há diferença entre os sexos quanto ao nível de atividade física habitual, tempo sedentário, quantidade e qualidade do sono em jovens atletas de badminton altamente treinados. Objetivos: O objetivo deste estudo foi comparar a atividade física habitual (AF), o tempo de sedentarismo e a duração e qualidade do sono em jovens atletas de badminton altamente treinados e de não atletas, do sexo masculino e feminino. Métodos: Vinte e sete jovens atletas de badminton e vinte e um não atletas (grupo controle) foram recrutados. A duração e a qualidade do sono (tempo total na cama, tempo total de sono, vigília após o início do sono, eficiência e latência do sono), counts totais, tempo em atividade vigorosa e tempo de sedentarismo foram medidos com um acelerômetro triaxial. Resultados: Atletas do sexo masculino tiveram menos tempo de sedentarismo (p = 0,028), mais tempo de atividade vigorosa(p = 0,016) e maior quantidade de counts totais (p < 0,001) do que o grupo controle masculino. Não houve diferença significante no tempo de sedentarismo (p = 0,702) ou tempo de atividade vigorosa (p = 0,205) entre as atletas e não atletas, mas as atletas do sexo feminino acumularam maior quantidade de counts totais que o grupo controle feminino (p = 0,003). Não houve diferença significante entre os sexos ou grupos para tempo na cama, tempo total de sono, eficiência do sono, vigília após o início do sono e latência (p> 0,05). Conclusões: Entre homens, mas não entre mulheres, os jovens atletas de badminton altamente treinados tiveram menor tempo de sedentarismo e maior tempo em atividades vigorosas do que os não atletas; entretanto, não houve diferença significante entre os sexos ou grupos na quantidade e qualidade do sono. Nível de evidência III; Estudo de caso controle .

Long rallies and next rally performances in elite men's and women's badminton.

The aim of the present study was twofold: (i) to identify contextual variables associated with the occurrence of long rallies while investigating time-related and technical parameters; and (ii) to identify performance differences between long rallies and the subsequent rally when accounting for match-context and the players' sex. The sample included 60 men's (n = 4,475 rallies) and 60 women's (n = 4,490 rallies) matches randomly selected from the 2015 World Badminton Super Series and World Championship (the final sample included long rallies that had an immediate next point played: n = 1,734 and n = 1,644 rallies for male and female players, respectively). The long rallies represented 19.4% (n = 867) and 16.5% (n = 822) of total rallies for male and female players, respectively. Long rallies were established using a two-step cluster model based on rally time and number of strokes for male (13-79s, 14-72 strokes) and female players (11-56s, 11-52 strokes). The variables collected were point outcome (when serving and receiving, winner, forced-error and unforced-error), number of strokes per rally, rally time, rest time, density, and time between strokes. The rallies were classified into different contexts (clusters) according to influencing factors with eight clusters for male players and three clusters for female players identified. Comparisons among clusters were conducted using Kruskal Wallis and one-way ANOVAs. Comparisons between long and immediate next points were conducted using the Wilcoxon tests for most variables and Crosstabs Command for point outcome and rallies (long and immediate next). Statistically significant differences were identified for both sexes among clusters only for time-related variables (i.e., rally time, rest time, density and time between strokes). In addition, a greater number of strokes, longer rally, rest time, and higher density were identified during long rallies compared with the immediate next rally for both men's and women's matches (p<0.05). The time between strokes during long rallies was significantly greater for male players during clusters 3, 5, 6, and 7 (p<0.05) and significantly lower for female players during all clusters (p<0.05). Significant relationships were identified between winning point outcome, and more unforced errors when serving during the immediate next rally (men's cluster 5 and women's cluster 2), and more winners when serving during the immediate next rally (men's cluster 6). The current study identified and characterised long rallies in elite men´s and women´s badminton matches highlighting the importance of sex and contextual factors on time-related and technical demands. Information obtained from these unique sequences of play (i.e., long and immediate next rallies) will assist coaches when modelling and simulating players' performances (i.e., physiologically and cognitively) during athlete preparation/competition.

Video Analysis Verification of Head Impact Events Measured by Wearable Sensors.

BACKGROUND: Wearable sensors are increasingly used to quantify the frequency and magnitude of head impact events in multiple sports. There is a paucity of evidence that verifies head impact events recorded by wearable sensors. PURPOSE: To utilize video analysis to verify head impact events recorded by wearable sensors and describe the respective frequency and magnitude. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Thirty male (mean age, 16.6 ± 1.2 years; mean height, 1.77 ± 0.06 m; mean weight, 73.4 ± 12.2 kg) and 35 female (mean age, 16.2 ± 1.3 years; mean height, 1.66 ± 0.05 m; mean weight, 61.2 ± 6.4 kg) players volunteered to participate in this study during the 2014 and 2015 lacrosse seasons. Participants were instrumented with GForceTracker (GFT; boys) and X-Patch sensors (girls). Simultaneous game video was recorded by a trained videographer using a single camera located at the highest midfield location. One-third of the field was framed and panned to follow the ball during games. Videographic and accelerometer data were time synchronized. Head impact counts were compared with video recordings and were deemed valid if (1) the linear acceleration was ≥20 g, (2) the player was identified on the field, (3) the player was in camera view, and (4) the head impact mechanism could be clearly identified. Descriptive statistics of peak linear acceleration (PLA) and peak rotational velocity (PRV) for all verified head impacts ≥20 g were calculated. RESULTS: For the boys, a total recorded 1063 impacts (2014: n = 545; 2015: n = 518) were logged by the GFT between game start and end times (mean PLA, 46 ± 31 g; mean PRV, 1093 ± 661 deg/s) during 368 player-games. Of these impacts, 690 were verified via video analysis (65%; mean PLA, 48 ± 34 g; mean PRV, 1242 ± 617 deg/s). The X-Patch sensors, worn by the girls, recorded a total 180 impacts during the course of the games, and 58 (2014: n = 33; 2015: n = 25) were verified via video analysis (32%; mean PLA, 39 ± 21 g; mean PRV, 1664 ± 619 rad/s). CONCLUSION: The current data indicate that existing wearable sensor technologies may substantially overestimate head impact events. Further, while the wearable sensors always estimated a head impact location, only 48% of the impacts were a result of direct contact to the head as characterized on video. Using wearable sensors and video to verify head impacts may decrease the inclusion of false-positive impacts during game activity in the analysis.

Lacrosse injuries among high school boys and girls in the United States: academic years 2008-2009 through 2011-2012.

BACKGROUND: Lacrosse is a fast growing youth sport in the United States. Although there have been published studies examining injuries associated with lacrosse, significantly less research has been conducted in high school lacrosse players than in older lacrosse players. The objective of this study was to compare high school lacrosse injury rates and patterns by type of athletic activity (ie, competition vs practice) and sex. HYPOTHESIS: Lacrosse injury rates and patterns differ by type of athletic activity and sex. STUDY DESIGN: Descriptive epidemiology study. METHODS: Using the High School RIO (Reporting Information Online) database, lacrosse exposure and injury data were collected during 4 academic years, 2008-2012, from a large sample of high schools in the United States. Schools' certified athletic trainers submitted exposure and injury information weekly. RESULTS: During the study period, 1406 injuries occurred during 716,812 athlete exposures, for an injury rate of 1.96 per 1000 athlete exposures (AEs). Injury rates were higher in competition than in practice (3.61 vs 1.23 per 1000 AEs, respectively; rate ratio [RR], 2.94; 95% CI, 2.65-3.27). Boys had a higher injury rate than girls (2.26 vs 1.54 per 1000 AEs, respectively; RR, 1.47; 95% CI, 1.32-1.64). The most common injury diagnoses among both boys and girls were sprains/strains (boys: 35.6%; girls: 43.9%) and concussions (boys: 21.9%; girls: 22.7%). The most commonly injured body sites in competition were the head/face (32.0%), lower leg/ankle/foot (17.8%), and knee (12.2%), while in practice, the most commonly injured body sites were the lower leg/ankle/foot (34.9%), head/face (16.4%), and knee (12.7%). Among boys, the most common mechanisms of injury were contact with another person (40.9%) and no contact (21.1%). Among girls, the most common mechanisms of injury were no contact (26.2%), contact with a playing apparatus (24.0%), and overuse/chronic (17.7%). Most injured athletes (71.8%) returned to activity in ≤21 days, but 6.9% of all injuries required surgery. CONCLUSION: Lacrosse injury rates and patterns among high school athletes in the United States differ by type of athletic activity and sex. Future studies should continue to compare differences in injury rates and patterns in high school lacrosse, with particular emphasis placed on high-risk plays in competition and the prevention and management of concussions in both boys and girls.

Differential analysis of the doping behaviour templates in three types of sports.

Conducted researches recognize various risk factors, as well as protective factors against doping behaviour in different sports i.e. sports disciplines or activities. The main goal of this research was to identify the correlation between selected socio-demographic, health-related, and sports-related predictors with doping factors in three different types of sports, which are (1) highly energetic demanding sports (weightlifting), (2) highly technical demanding sports (racquet sports), and (3) highly tactical demanding sports (sailing). The research consisted of three separate studies, each one of them researching one of the sports. The sample of subjects included altogether 293 athletes, senior level competitors (older than 18years of age). In total, the sample comprised three homogenous sub-samples, as follows: athletes in highly energetic demanding sports (weightlifters and power lifters; N=27), athletes in highly technical demanding sports (table tennis, tennis and badminton players; N=188), and athletes in highly tactical demanding sports (sailing; N=78). The first study involved weightlifters where we should point out the existence of high doping behaviour In this study, religiousness was interpreted as the most significant protective factor against doping behaviour, while sports factors are not found to be significantly related to doping. The study involving racquet sport athletes suggests a high risk of doping behaviour among those athletes who observe doping behaviour in their sport. We noticed low levels of athletes' trust in their coaches' and physicians' opinions on doping issues. This is an issue which should be researched in the future, because the underlying cause has not been studied as yet. Briefly, it seems that either the athletes are not convinced of their coaches '/physicians' expertise regarding doping issues, and/or they do not believe in their good intentions. It is particularly important, as the previous research has shown that with the increased trust in coaches and physicians, the chance that an athlete will use doping decreases. As expected, it is characteristic for sailing that it has a low likelihood of potential doping behaviour, although the consumption of dietary supplements is high. Substance abuse in sports spreads beyond those that enhance athletic performance. All of these issues should be studied in more detail in the future and, if appropriately validated, incorporated into anti-doping intervention programs.

Gender differences in game responses during badminton match play.

The aim of this study was to evaluate possible gender differences in match play activity pattern [rally duration, rest time between rallies, effective playing time, and strokes performed during a rally] and exercise intensity (heart rate [HR], blood lactate [La], and subjective ratings of perceived exertion [RPE]) during 9 simulated badminton matches in male (n = 8) and female (n = 8) elite junior (16.0 ± 1.4 years) players. Results showed significant differences (all p < 0.05; effect size (ES) = 0.80-1.56) between male and female players in the activity pattern of match play, with male players engaged in longer rallies (6.8 ± 4.8 vs. 5.7 ± 3.1 seconds), executing more strokes per rally (6.4 ± 4.8 vs. 4.7 ± 2.8) and resting more between rallies (10.5 ± 8.8 vs. 8.8 ± 7.2 seconds) than female players. No clear differences (all p > 0.05; ES = -0.33 to 0.08) were observed between female or male players in average HR (174 ± 7 vs. 170 ± 9 b·min(-1)), %HRmax (89.2 ± 4.0% vs. 85.9 ± 4.3%), La (2.5 ± 1.3 vs. 3.2 ± 1.8 mmol·L(-1)), and RPE values (14.2 ± 1.9 vs. 14.6 ± 1.8) during match play, although male players spent more time (moderate effect sizes) at intensities between 81 and 90% HRmax (35.3 ± 17.9 vs. 25.3 ± 13.6; p < 0.05; ES = 0.64) in the second game. There seemed to be a trend toward an increased playing intensity (i.e., higher HR, La, and RPE) from the first to the second game, highlighting the higher exercise intensity experienced during the last part of the match. The clear between-gender differences in activity patterns induced only slightly different physiological responses.

Sex differences in relative age effects among Japanese athletes.

The present study investigated the relative age effect (RAE), a biased distribution of elite athletes' birthdates, in Japanese female athletes. Japan applies a unique annual-age grouping for sport and education, which is from April 1 to March 31 of the following year. A total of 1,335 female athletes were evaluated from six sports: softball, soccer, volleyball, basketball, badminton, and track and field (long distance), and compared with male athletes. All athletes played in the top level of Japanese leagues for each sport in 2010. Distribution of the birth dates in each female sport showed a significant RAE only in volleyball. For males, significant RAEs were observed in baseball, soccer, and track and field. Findings suggest that the determinants of RAEs in sports may differ between males and females.

Is there a danger for myopia in anti-doping education? Comparative analysis of substance use and misuse in Olympic racket sports calls for a broader approach.

BACKGROUND: Racket sports are typically not associated with doping. Despite the common characteristics of being non-contact and mostly individual, racket sports differ in their physiological demands, which might be reflected in substance use and misuse (SUM). The aim of this study was to investigate SUM among Slovenian Olympic racket sport players in the context of educational, sociodemographic and sport-specific factors. METHODS: Elite athletes (N=187; mean age=22±2.3; 64% male) representing one of the three racket sports, table tennis, badminton, and tennis, completed a paper-and-pencil questionnaire on substance use habits. Athletes in this sample had participated in at least one of the two most recent competitions at the highest national level and had no significant difference in competitive achievement or status within their sport. RESULTS: A significant proportion of athletes (46% for both sexes) reported using nutritional supplements. Between 10% and 24% of the studied males would use doping if the practice would help them achieve better results in competition and if it had no negative health consequences; a further 5% to 10% indicated potential doping behaviour regardless of potential health hazards. Females were generally less oriented toward SUM than their male counterparts with no significant differences between sports, except for badminton players. Substances that have no direct effect on sport performance (if timed carefully to avoid detrimental effects) are more commonly consumed (20% binge drink at least once a week and 18% report using opioids), whereas athletes avoid substances that can impair and threaten athletic achievement by decreasing physical capacities (e.g. cigarettes), violating anti-doping codes or potentially transgressing substance control laws (e.g. opiates and cannabinoids). Regarding doping issues, athletes' trust in their coaches and physicians is low. CONCLUSION: SUM in sports spreads beyond doping-prone sports and drugs that enhance athletic performance. Current anti-doping education, focusing exclusively on rules and fair play, creates an increasingly widening gap between sports and the athletes' lives outside of sports. To avoid myopia, anti-doping programmes should adopt a holistic approach to prevent substance use in sports for the sake of the athletes' health as much as for the integrity of sports.

Medical supervision of young female athletes training in complex coordinational sports.

UNLABELLED: This article proposes simple medical criteria that can be used by trainers and others for effective medical supervision of young female athletes. METHODS: The cross-sectional, age-stratified study compared girls 10-17 years of age involved in intensive training in gymnastic floor exercises, trampoline, or badminton. Each sport and/or control group was represented by 40-45 girls. Data included medical history, morphometric variables and observation of biological development. RESULTS: Gymnasts started training earliest (approximately 5-years-old) and trained most intensely (18-20 h/wk), followed by trampolinists and then badmintonists. Height, weight, body mass index, and % body fat were reduced in athletes, with gymnasts showing the greatest reduction. Athletes showed higher ratios of leg length to height and shoulder width/hip width, and smaller pelvic size compared to height. The average age of menarche of gymnasts was 13.8 (1.6 year later than controls). Delays of biological development of more than 2 years were common in athletes, and some gymnasts showed more than a 4-year delay. These delays were related to morphometric indicators of hormonal imbalance and to low body fat. Gymnasts had more childhood diseases, with an infection index of 2.8 compared to 1.1 for the control group, and had a higher level of chronic ENT problems. CONCLUSIONS: Trainers need to protect the health of athletes. During the course of training, anamneses, delayed menarche and other signs of delayed biological development must be monitored. Morphometric measures and indicators of biological development are proposed to provide simple criteria important in protecting the athletes' health.

Neuromuscular fatigue in racquet sports.

This article describes the physiologic and neural mechanisms that cause neuromuscular fatigue in racquet sports: table tennis, tennis, squash, and badminton. In these intermittent and dual activities, performance may be limited as a match progresses because of a reduced central activation, linked to changes in neurotransmitter concentration or in response to afferent sensory feedback. Alternatively, modulation of spinal loop properties may occur because of changes in metabolic or mechanical properties within the muscle. Finally, increased fatigue manifested by mistimed strokes, lower speed, and altered on-court movements may be caused by ionic disturbances and impairments in excitation-contraction coupling properties. These alterations in neuromuscular function contribute to decrease in racquet sports performance observed under fatigue.

Unprotected eyes in squash: not seeing the risk of injury.

The use of appropriate eyewear in squash can protect the eyes against injury. However, few adult squash players adequately protect their eyes against potential severe injuries. We describe the characteristics of non-users of protective eyewear and examine predictors of appropriate eyewear use. Self-report surveys of adult players were conducted in metropolitan Melbourne, Australia. Information on players' knowledge, behaviours and attitudes associated with protective eyewear use was collected, in addition to player demographic data. Appropriate eyewear was defined as Standards-approved polycarbonate lens eyewear. The majority 92.2% of players did not adequately protect their eyes while playing squash. Significant predictors of reported eyewear use were: previous eye injury: playing squash on average more than 2 hr per wk: having played for more than 20 y; and having more favourable attitudes towards eye safety in squash. The significant predictors of appropriate eyewear use were: being female; previous eye injury; playing squash on average more than 2 hr per week; and having more favourable attitudes towards eye safety in squash. Understanding the characteristics of both users and non-users of appropriate eye protection in squash is essential for informing future prevention strategies.

Are squash players protecting their eyes?

OBJECTIVE: To determine factors associated with adult squash players' protective eyewear behaviours. METHODS: A survey of 303 players (aged >or =18 years) was conducted at three squash venues in Melbourne, Australia over a three week period in June 2000 to obtain information about protective eyewear use. RESULTS: Of 303 participants the response rate was 98.1%; 66.1% were males, with a mean age of 40.5 years. The majority (68.4%) had played squash for 10 years or more. Although 18.8% of players reported using protective eyewear, only 8.9% reported wearing approved eyewear. Both age group (p<0.05) and years of squash experience (p<0.01) were significantly associated with any eyewear use. The two main influences were personal experience of eye injuries (50.0%) and knowledge of eye injury risk (33.9%). A commonly reported barrier was restriction of vision (34.2%). CONCLUSION: These findings demonstrate a low prevalence of voluntary use of appropriate protective eyewear. Future prevention strategies incorporating education campaigns should focus on increasing players' knowledge of risks. The barriers to use and misconceptions about which types of eyewear is most protective need to be addressed as a priority.

Painful conditions in the Achilles tendon region: a common problem in middle-aged competitive badminton players.

Overuse injuries are the most frequent type in badminton, generally localized in the legs. An earlier study found 32% of young Swedish elite badminton players to have experienced disabling pain in the Achilles tendon region during the previous 5 years. The present investigation examined the prevalence and characteristics of painful conditions in the Achilles tendon region in 32 middle-aged competitive badminton players by means of questionnaire and physiotherapist's examination. Pain in the Achilles tendon region was reported by 44%, either presently or during the past 5 years, generally localized in the middle portion of the tendon. Symptoms had lasted 2 weeks-1 year (96 days). On the competition days 22% of the reported pain currently in the region. Age was found to be correlated to Achilles tendon pain, but there was no relationship between symptoms of pain and body mass index, gender, training quantity, or years of playing badminton. In conclusion, Achilles tendon pain seems to be relatively common among Swedish middle-aged competitive badminton players, particularly in the older ones.

Painful conditions in the Achilles tendon region in elite badminton players.

The purpose of this study was to investigate the prevalence and characteristics of painful conditions in the Achilles tendon region in elite badminton players. The study group consisted of 66 players in the Swedish elite division (highest level) in badminton, 41 men (mean age, 24.4 years) and 25 women (mean age, 21.9 years). Twenty-one players (32%) reported the occurrence of a disabling painful condition in the Achilles tendon region during the previous 5 years, and 11 players (17%) had an ongoing painful condition. A majority of the painful conditions (12 of 21, or 57%) were described as involving the midportion of the Achilles tendon. The players who had a painful condition reported a significantly higher weekly training load as measured by the number of hours spent in total training, badminton training, and endurance and strength training. There were no differences in age, sex, and body mass index between the players with and without painful conditions in the Achilles tendon region.

[Preventive measures against ocular trauma on squash courts]. / Prévalence des mesures de protection contre les traumatismes oculaires par balle de squash.

AIM: Squash-ball induced trauma is an important cause of severe ocular injuries. Fortunately they can be prevented by wearing of protective goggles. The aim of this study was to investigate the prevalence of these protective devices in Swiss Squash Clubs. METHODS: A detailed questionnaire was sent to all Squash Clubs in Switzerland (n = 82). The solicited information comprised: the possibility to buy protective goggles in the proshop, presence of posters in the club encouraging the members to wear protective goggles, assessment of the risk of ocular trauma by a squash ball (high or low), and the evaluation of ocular sequelae after squash ball injury. RESULTS: In the French-speaking part of Switzerland 35% of the clubs responded, whereas the percentage in the German-speaking part was 32% did. Of all the clubs who returned the questionnaire only one was found to sell protective goggles in the sports centre (4%). Two further clubs had posters encouraging the players to wear eye protection (7%). Three other clubs in the French-speaking area and two in the German-speaking area planned to introduce these measures (18%). 63% of the clubs considered the risk of an ocular injury to be low, 7% even as very low. Only 26% of the clubs who returned the questionnaire considered the risk to be much higher. CONCLUSION: The interest of squash clubs in protective eye wear is very low, as the risks for a serious ocular injury are underrated. It is therefore important to bring the danger of racket sports to the attention of patients.

Development, application, and limitation of a stochastic Markov model in explaining championship squash performance.

This study reports a stochastic (Markov) model for squash which uses empirical data to transit event states on a shot by shot basis. This offers more information than traditional models with regard to how points were won or lost and the potential for predicting future athletic performance from a priori observation. The predictive capacity of the model, however, is presently restricted because the observed behaviors (shots) and associated outcomes (winners, errors and lets) are statistically variant (p < .25). A player does not produce a consistent athletic response to the same preceding condition when competing against different opponents, although it is unclear at present whether this observation is a function of the particular analysis employed. Nevertheless, the modeling of athletic behavior is a way to search for critical data which underpin competitive sport performance.

Badminton injuries--a prospective epidemiological and socioeconomic study.

During a 1-year period 100 badminton players were registered and treated in the casualty ward of Randers City Hospital, Denmark. The injuries to the badminton players constituted 5% of all sports injuries registered during the same period in the casualty ward. At follow-up questionnaires were sent to all participants. Replies were received from 89 patients. Over the same period all sports participants in the hospital catchment area (30,254) were registered according to their sport affiliation (2620 badminton players-1650 men and 970 women). Of those injured 58% were men (mean age 31 years) and 42% were women (mean age 25 years). Of the injuries 55% occurred in club players, the remainder occurring during company and school sports activities. The active players were classified into three groups according to age: Group 1 under 18 years (31%); Group 2 18-25 years (16%); Group 3 more than 25 years (53%). According to the Abbreviated Injury Scale (AIS) 17% of the injuries were classified as minor, 56% as moderate, and 27% as severe, respectively. Of the severe injuries (AIS = 3) 56% were found in the oldest age group. AIS correlated with time absent from sport (P < 0.001). Nine players (9%) reported that earlier injuries had influenced the actual accident. Most players (96%) trained one to three times a week. Sprains were the injury most commonly diagnosed (56%), fractures accounted for 5%, torn ankle ligaments were found in 10%, and 13% had ruptures to the Achilles tendon. Overall, 21% were admitted to hospital. None of the patients treated as inpatients was kept in hospital for more than 7 days. The injury caused 56% of players to be absent from work of whom 23% were absent for more than 3 weeks. After the injury 12% of the players gave up their sport, and only 4% restarted their training/sport within 1 week. As many as 28% had to avoid training and playing in matches for 8 weeks or more.