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1.
The aim of this study was to identify anthropometric and biomotor variables that discriminated among groups of elite adolescent female athletes aged 14.3 +/- 1.3 years (mean +/- s) from four different sports (tennis, n = 15; swimming, n = 23; figure skating, n = 46; volleyball, n = 16). The anthropometric variables included body mass, height, bi-epicondylar breadth of the distal extremity of the humerus and femur, maximal girth of the calf and biceps and the sum of five adipose skinfolds. The biomotor variables were maximal aerobic power, muscular endurance and flexibility of the trunk. Discriminant analysis revealed three significant functions (P < 0. 05). The first discriminant function primarily represented differences between figure skaters and all other groups of athletes. The other two underlined anthropometric and biomotor differences between swimmers and volleyball players and between tennis players and swimmers, respectively. After validation, the analysis showed that 88% of the athletes were correctly classified in their respective sports. Our model confirms that elite adolescent female athletes show physical and biomotor differences that clearly distinguish them according to their particular sport.  相似文献   

2.
ABSTRACT

The purpose of the study was to assess (a) the prevalence of disordered eating (DE) in elite female team sports players compared to non-athletes and (b) to compare DE prevalence in elite female players in basketball, volleyball and water polo. One hundred and seventy-five females were recruited (age 23.10?±?5.4, BMI 21.85?±?2.3?kg/m2), 53 were elite basketball players, 42 were elite volleyball players, 34 were elite water polo players and 46 were non-athletes. Participants completed the Eating Disorders Questionnaire (EDE-Q) and a physical activity questionnaire. The EDE-Q incorporates 36 statements which relate to the occurrence and frequency of key behaviours of eating disorders, under the following four subscales: Restraint, eating concern, shape concern and weight concern and a global score of disordered eating. No differences were found in the EDE-Q subscale score and global score between athletes and non-athletes. Only 6.2% of the total number of participants exhibited DE using the global score >2.3. Water polo players had significantly higher scores in the ‘eating concern’ subscale and in the frequency of key behavioural features of DE such as binge eating episodes and objective and subjective bulimic episodes, compared to volleyball and basketball players. In conclusion, team sport elite female players do not exhibit greater prevalence of DE compared to non-athletes. Water polo, a sport that emphasises leanness and control of body weight for international distinctions, is associated with a higher tendency to exhibit DE, when compared to other team sports.  相似文献   

3.
Abstract

Talent identification in team sports is complex and requires a multidisciplinary approach. The purpose of this study was to examine differences between elite and non-elite handball players in three age groups: U14 (n=186), U16 (n=150), and U18 (n=92). A multidimensional test battery was assessed, taking biological maturation into account. Significant maturation effects were found for all anthropometric characteristics and most performance variables. Compared with their non-elite peers, the elite handball players demonstrated significantly greater aerobic capacity (P<0.01), strength and power (U14: countermovement jump, P=0.021; sit-ups, P=0.003; handgrip, P=0.020; U16: countermovement jump, P=0.013; five-jump test, P<0.001), and speed and agility (P<0.05) when maturation was controlled for. There was a significant difference in flexibility between elite and non-elite players in the U18 group (P<0.05). The elite and non-elite players did not differ in task- and ego-orientation. These results show that elite and non-elite young handball players possess different physical performance characteristics and that the specific tests that discriminate elite from non-elite handball players vary among age groups. In addition, maturity status can influence the results and should therefore be considered in talent identification and development programmes.  相似文献   

4.
The primary aim of this cross-sectional study was to compare subjective correlates of health, such as nutrition, self-esteem, sleep and stress, between adolescent elite athletes (n?=?625) and a reference group of adolescents (n?=?391) not involved in elite sports. A secondary aim was to study predictors for self-perceived stress. A questionnaire was e-mailed to all participants containing valid questions about competence-based self-esteem, nutrition, self-perceived stress and sleep. Our results show that adolescent elite athletes reported significantly (p?p?相似文献   

5.
Abstract

Aspects of team players' performance are negatively affected when ~ 2% body mass is lost by perspiration. Although such dehydration is likely reached during summer practice in outdoors sports, it is unclear if such dehydration is achieved during the practice of indoor sports. We assessed the fluid and electrolyte deficits of elite team players during practice for the following indoor sports: indoor soccer (n=9), basketball (n=11), volleyball (n=10), and handball (n=13). Morning hydration status was estimated by measuring urine specific gravity. Sweat rate was calculated from body mass changes and fluid intake. Sweat sodium concentration from the forearm was used to estimate whole-body sodium losses. Over 91% of the players were moderately hypohydrated (urine specific gravity>1.020) at waking 3 h before practice. Indoor soccer players sweated at a higher rate (1.8 litres · h?1) than volleyball and handball players (1.2 and 1.1 litres · h?1, respectively; P<0.05), whereas sweat rate was not different between basketball players (1.5 litres · h?1) and the other team sport players (P>0.05). In average, 62±13% of sweat losses were replaced and teams' body mass loss did not exceed 1.2±0.3%. Sodium losses were similar among teams, averaging 1.2±0.2 g. The exercise fluid replacement habits of professional indoor team players are adequate to prevent 2% dehydration. However, most players could benefit from increasing fluid intake between workouts to offset the high prevalence of morning hypohydration.  相似文献   

6.
The purpose of this study was to examine the relationship between the upper limb anthropometric dimensions and a history of dominant upper limb injury in tennis players. Dominant and non-dominant wrist, forearm, elbow and arm circumferences, along with a history of dominant upper limb injuries, were assessed in 147 male and female players, assigned to four groups based on location of injury: wrist (n = 9), elbow (n = 25), shoulder (n = 14) and healthy players (n = 99). From anthropometric dimensions, bilateral differences in circumferences and in proportions were calculated. The wrist group presented a significant bilateral difference in arm circumference, and asymmetrical bilateral proportions between wrist and forearm, as well as between elbow and arm, compared to the healthy group (6.6 ± 3.1% vs. 4.9 ± 4.0%, P < 0.01; ?3.6 ± 3.0% vs. ?0.9 ± 2.9%, P < 0.05; and ?2.2 ± 2.2% vs. 0.1 ± 3.4%, P < 0.05, respectively). The elbow group displayed asymmetrical bilateral proportions between forearm and arm compared to the healthy group (?0.4 ± 4.3% vs. 1.5 ± 4.0%, P < 0.01). The shoulder group showed significant bilateral difference in elbow circumference, and asymmetrical bilateral proportions between forearm and elbow when compared to the healthy group (5.8 ± 4.7% vs. 3.1 ± 4.8%, P < 0.05 and ?1.7 ± 4.5% vs. 1.4 ± 4.3%, P < 0.01, respectively). These findings suggest that players with a history of injury at the upper limb joint present altered dominant upper limb proportions in comparison with the non-dominant side, and such asymmetrical proportions would appear to be specific to the location of injury. Further studies are needed to confirm the link between location of tennis injury and asymmetry in upper limb proportions using high-tech measurements in symptomatic tennis players.  相似文献   

7.
Abstract

The effect of intellectual impairment on sports performance has received limited attention by researchers. As a contribution to closing this gap, the purpose of the present investigation was to examine the differences in tactical proficiency between table tennis players with and without intellectual disabilities (ID). These groups were matched for training-volume and experience and consisted of 41 male (age = 27±8) and 30 female (age= 28±8) elite players with ID and a reference group of 12 male (age= 24±12) and 5 female (age= 20±9) players without ID. In two different test settings – one a World Championship and the other a training camp – the players in each group performed 60 semi-standardised rallies against the same opponent. Players were told that 12 sets of five identical services would be delivered, and their goal was to return the service with the intention of ‘winning the point’. The test results were validated for this study, to compute tactical proficiency scores (maximal score of eight points) for each player. A two-way Analysis of Variance (ANOVA) revealed significantly lower proficiency scores for players with ID than for those without ID. Repeated-measures ANOVA revealed that within each series of five rallies, starting with identical services, all participants were able to significantly improve their tactical proficiency gradually, but players without ID scored 4.3±0.5 from the first ball on, and while athletes with ID only 3.3±0.7 after five balls. The results of this study indicate that ID is associated with decreased tactical proficiency in table tennis.  相似文献   

8.
ABSTRACT

Talent detection intends to support lifelong sports participation, reduce dropouts and stimulate sports at the elite level. For this purpose it is important to reveal the specific profile which directs children to the sports that connect to their strengths and preferences. This study evaluated a perceptuomotor skills assessment as part of talent detection for table tennis, a sport in which perceptuomotor skills are considered essential to cope with the difficult technical aspects. Primary school children (n = 121) and gifted young table tennis players (n = 146) were assessed using the Dutch perceptuomotor skills assessment measuring “ball control” and “gross motor function”. A discriminant function analysis confirmed the added value by identifying primary school children fitting the table tennis perceptuomotor profile of the young gifted table tennis players (28%). General linear model analyses for the assessment’s individual test items showed that the table tennis players outperformed their primary school peers on all “ball control” items (P < 0.001). In conclusion, the assessment appears to be of added value for talent detection in table tennis at this young age. Longitudinal studies need to reveal the predictive value for sports participation and elite sports.  相似文献   

9.
Growth and maturation impact the selection, development and progression of youth athletes. Individual differences in the growth and maturity may afford a performance advantage, clouding coaches and practitioners’ perceptions regarding current ability and future potential. This may result in the exclusion of talented, yet less physically gifted athletes. Participants were 91 male (n = 47) and female (n = 44) elite British Junior tennis players, 8–17 years of age (12.5 ± 1.9 years). Height and body mass were measured and compared to growth charts; hand-wrist radiographs were taken. Skeletal age (SA) was estimated with the Fels method and contrasted to chronological age (CA). Mean height and body mass of individual players ranged between the 50th and 90th centiles for age and sex. Females were advanced in SA relative to CA (0.3–0.89 years.) from 8 years. Males were average to delayed in maturation from 8 to 12 years, but advanced in SA from 14 to 16 years (0.75–1.23 years). Individual differences in growth and maturation appear to contribute towards the selection of elite junior tennis players, with a bias towards males and females who are advanced in maturation and comparatively tall and heavy for their age. This has important implications for talent identification and development.  相似文献   

10.
对网球运动成败归因的科学研究不仅为丰富运动训练学、运动心理学理论提供实证依据,对网球运动训练的科学化也具有借鉴意义。采用质性研究法以男子网球运动员在大赛后的访谈材料为研究对象,对当前优秀男子网球运动员竞赛成败归因进行详细的研究、分析。结果表明,优秀男子网球运动员的成败基本归因是一致的。从自由节点和相应的总参考点数来看,国内、外优秀男子网球运动员对于失败归因不同。从相应节点比例来看,成功时,国外运动员的归因更加细致和多元化,而失败时,国内男子网球运动员的归因更多。  相似文献   

11.
The purpose of this study was to determine the influence of muscle strength, trainingspecific and anthropometric parameters on bone mineral density (BMD) in male top athletes of different sports in comparison to untrained controls. BMD was measured by dual energy X-ray absorptiometry in 173 males, aged 18 to 31 years. Of these, 104 were athletes (runners, n = 21; cyclists, n = 12; triathletes, n = 18), heavy athletes (HA, judo and wrestling, n = 28), and team sport athletes (TS, handball, soccer, basketball, volleyball, n = 25); 44 were unspecifically trained sport students (STU); and 25 were untrained controls (UT). Sport- and group-specific differences were found in anthropometric but not strength parameters. Marked sport- and group-specific differences were found for BMD at lumbar spine (LSP) and the femoral sites (FEM). Group-specific effects on BMD were clearest when calculating percentual differences between BMD of athletes and UT: In group I (HA, TS, and STU), BMD at LSP and FEM were significantly (p < .01) higher compared to UT; in group II (R and TRI), BMD at FEM but not at LSP was higher compared to UT (p <.01); and in group III (C), no BMD value was significantly different from UT. Multiple regression analysis revealed lean body mass to be the strongest predictor for BMD at LSP and FEM. We conclude that mechanical loads have strong effects on bone adaptation. Sport-specific and body region-specific effects have to be taken into account for evaluation of osteogenic effects of exercise. Particularly dynamic sports with short, high, and multidimensional loads have the strongest effects on bone formation, independent of training quantity.  相似文献   

12.
Bone turnover is affected by exercise throughout the lifespan, especially during childhood and adolescence. The objective of this study was to investigate the impact of different sports on total and regional bone mineral density in male Brazilian adolescent athletes. Forty-six adolescents aged 10-18 years participated in the study: 12 swimmers, 10 tennis players, 10 soccer players, and 14 sedentary individuals. The athletes had engaged in physical activities for more than 10 h per week in the previous 6 months. Bone mineral density of the lumbar spine (L1-L4), left proximal femur region, and whole body was evaluated by dual-energy X-ray absorptiometry. Results showed higher mean values in the proximal femur region of tennis and soccer players (1.02 ± 0.18; 0.96 ± 0.16, respectively) than swimmers and controls (0.91 ± 0.14 and 0.87 ± 0.06, respectively) (P < 0.05). In relation to the impact of sporting activities based on bone age determination, we observed significant differences in bone mineral density at all evaluated sites at the end of puberty (16-18 years) compared with 10-12 years, with increases of 78% in the lumbar spine, 47% in the proximal femur, and 38% in the whole body.  相似文献   

13.
Purpose: The purpose of this study was to determine magnitudes of differences for anthropometric and athletic performance scores between high school and elite college-level American football players. Method: Participants included high school-age (n = 3,666) athletes who participated in American football combines, as well as elite college-level (n = 5,537) athletes who participated in the National Football League (NFL) scouting combine. Combine data included position; height; weight; 10-, 20-, and 40-yard dash; pro-agility (PA); L-cone drill (LC); vertical jump (VJ); and broad jump (BJ). Athletes were separated into their respective position group, defensive back (DB), wide receiver (WR), linebacker (LB), quarterback (QB), running back (RB), tight end (TE), defensive line (DL), and offensive line (OL) for analysis of performance differences. Percent differences for each dependent variable were calculated to quantify magnitudes of differences. Results: NFL combine participants scored 3% to 25% better on all measurements, with the largest differences between weight and VJ (14%–25%). Conclusion: The largest measurement-specific differences between high school-age and elite college-level American football players were body size and power. Although it may seem intuitive that elite college-level players would perform better, these data provide a unique perspective to high school players, parents, and coaches, giving new information to use when designing measurement-specific athletic development programs. Thus, strength and conditioning professionals may benefit from emphasizing increases in muscle mass and power output in strength and conditioning programs.  相似文献   

14.
This study compared the neuromuscular, metabolic and hormonal profiles of trained prepubescent tennis players and an untrained group. The boys in the experimental group (n = 9; mean age ± S.D. = 11.4 ± 0.5 years) had participated in tennis training for 2.3 ± 1.0 years and the boys in the control group (n = 9; mean age ± S.D. = 10.9 ± 0.4 years) were normal active volunteers. The tennis players were found to be physically more active than the controls when the comparison was made for either 1 year (4.9 ± 1.8 vs 2.6 ± 2.5 times per week; P<0.05) or for 1 week (3.4 + 1.2 vs 0.4 ± 0.5 times; P < 0.001) preceding the tests. Choice reaction time was significantly (P <0.01) shorter in the experimental group (258 ± 16 ms) than in the control group (344 + 81 ms). Dropping height in the best drop jump was significantly (P< 0.05) higher in the tennis players (0.46 + 0.19 m) than in the control boys (0.27 ± 0.10 m). The tennis players had significantly lower oxygen consumption at the ‘anaerobic threshold’ than the controls (P < 0.05). There were no significant differences between the groups in serum hormone levels. The small differences that existed may have been caused by actice participation in sport by the tennis players.  相似文献   

15.
Task-specific auditory training can improve sensorimotor processing times of the auditory reaction time (RT). The majority of competitive swimmers do not conduct habitual start training with the electronic horn used to commence a race. We examined the effect of four week dive training interventions on RT and block time (BT) of 10 male adolescent swimmers (age 14.0 ± 1.4 years): dive training with auditory components (speaker and electronic horn) (n = 5) and dive training without auditory components (n = 5). Auditory stimulus dive training significantly reduced swimming start RT, compared with dive training without auditory components (p < 0.01), with a group mean RT reduction of 13 ± 9 ms. Four of the five swimmers that received auditory stimulus training showed medium to large effect size reductions in RT (d = 0.74; 1.32; 1.40; 1.81). No significant changes to swimmers’ BTs were evident in either dive training intervention. The adolescent swimmers’ results were compared against six male elite swimmers (age 19.8 ± 1.0 years). The elite swimmers had significantly shorter BTs (p < 0.05) but no significant difference in RTs. Auditory stimulus dive training should be explored further as a mechanism for improving swimming start performance in elite swimmers who have pre-established optimal BTs.  相似文献   

16.
To determine the relationship between multidimensional performance characteristics and level of performance in talented youth field hockey players, elite youth players (n = 38, mean age 13.2 years, s = 1.26) were compared with sub-elite youth players (n = 88, mean age 14.2 years, s = 1.26) on anthropometric, physiological, technical, tactical and psychological characteristics. Multivariate analyses with performance level and gender as factors, and age as the covariate, showed that the elite youth players scored better than the sub-elite youth players on technical (dribble performance in a peak and repeated shuttle run), tactical (general tactics; tactics for possession and non-possession of the ball) and psychological variables (motivation) (P <?0.05). The most discriminating variables were tactics for possession of the ball, motivation and performance in a slalom dribble. Age discriminated between the two groups, indicating that the elite youth players were younger than the sub-elite players. In the guidance of young talented players to the top as well as in the detection of talented players, more attention has to be paid to tactical qualities, motivation and specific technical skills.  相似文献   

17.
Abstract

The aim of this study was to analyse the temporal structure of individual tennis play on hard courts in adolescence. Thirty-two national-level tennis players (16 females, 16 males) participated in the study (age 15.6±0.9 years, weight 61.7±1.4 kg, height 1.70±0.14 m). All participants played an official competition on hard courts and with the same type of balls. Games were recorded for later analysis of total play time, real play time, and resting time, both in absolute values and as a percentage of total time. The average duration of a point and the number of strokes per rally were also determined. Results showed no differences based on gender, with a total play time of 105.00±20.00 min, real play time of 31.50±5.83 min, and resting time of 73.5±8.50 min. The ratio of work to resting time was 1:2.7, the number of strokes per rally was 5.12±0.17, and a point lasted an average of 9.08±0.60 s. Our results show the importance of keeping in mind the technical evolution of players at this age, with the goal of reaching maximum athletic performance. The adolescent players showed approximately the same number of strokes per rally, but with a greater average duration compared with adult elite athletes.  相似文献   

18.
Abstract

Injuries are common among athletes, and are sometimes so severe that they affect an athlete's career in sport. As studies on sport career termination are few, we conducted a study to investigate the role of injuries as a reason for ending a sport career. The study group consisted of 574 male and female top-level cross-country skiers, swimmers, long-distance runners and soccer players who responded to a retrospective postal questionnaire in 2006. Twenty-seven athletes (4.9%, 27/548) reported ending their sport career because of injury. A follow-up interview was conducted by telephone in 2007 (n=20 volunteered to be interviewed) to confirm sport career termination and the reasons for this. Fifteen of the interviewed athletes terminated and five continued their sport on the same level as earlier. Female athletes (12/15) terminated their sport career more frequently than male athletes (3/15). Athletes who reported terminating their sport career because of injury were on average two and a half years older (24.1 years vs. 21.6 years, P=0.006) than athletes who continued the sport. All the swimmers (n=5) who were interviewed terminated their career because of a shoulder injury. All the soccer players who ended their career (n=4) were female and had a severe knee injury, such as anterior cruciate ligament injury. Most of the athletes who terminated their sport career (70.4%, 19/27) reported that the injury caused them mild or moderate permanent disability. We found that sports injuries play a significant role in terminating a career in sport, and in some sports events injuries may commonly be the main reason for sport career termination. Injury prevention and adequate treatment and rehabilitation of injuries are thus essential to avoid the long-term consequences of severe sport injuries.  相似文献   

19.
This study presents the kinematics and plantar pressure characteristics of eight elite national-level badminton athletes and eight recreational college-level badminton players while performing a right-forward lunge movement in a laboratory-simulated badminton court. The hypothesis was that recreational players would be significantly different from elite players in kinematics and plantar pressure measures. Vicon® motion capture and Novel® insole plantar pressure measurement were simultaneously taken to record the lower extremity kinematics and foot loading during stance. Recreational players showed significantly higher peak pressure in the lateral forefoot (P = 0.002) and force time integral in the lateral forefoot (P = 0.013) and other toes (P = 0.005). Elite athletes showed higher peak pressure in the medial forefoot (P = 0.003), hallux (P = 0.037) and force time integral in the medial forefoot (P = 0.009). The difference in landing techniques for the lunge step between elite athletes and recreational players was observed with peak ankle eversion (?38.2°±2.4° for athletes and ?11.1°±3.9° for players, P = 0.015); smaller knee range of motion in the coronal and transverse planes, with differences in peak knee adduction (28.9°±6.8° for athletes and 15.7°±6.2° for players, P = 0.031); peak knee internal rotation (20.3°±1.3° for athletes and 11.8°±3.2° for players, P = 0.029) and peak hip flexion (77.3°±4.1° for athletes and 91.3°±9.3° for players, P = 0.037).  相似文献   

20.
In many competitive sports, the use of a cut-off date for junior competition has been associated with a skewed birth date distribution in junior and senior players. The International Tennis Federation uses a junior competition year that commences on 1 January. The purpose of the current investigation was to describe the birth date distribution of 448 elite senior tennis players and 476 elite junior tennis players. There was a significant season of birth bias among elite senior players (P <?0.001), with 58.9% being born in the first 6 months of the year. There was also a significant season of birth bias among elite junior players (P <?0.001), with 59.5% being born in the first 6 months of the year. This pattern was observed in both male and female players as well as in players from different regions. The results provide evidence that it is the cut-off date for the junior competition year that is responsible for the skewed birth date distribution in tennis rather than regional or climatic factors.  相似文献   

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