Gaze Behavior and Cognitive Performance on Tasks of Multiple Object Tracking and Multiple Identity Tracking by Handball Players and Non-Athletes.

Multiple object tracking (MOT) and multiple identity tracking (MIT) each measure the ability to track moving objects visually. While prior investigators have mainly compared athletes and non-athletes on MOT, MIT more closely resembles dynamic real-life environments. Here we compared the performance and gaze behavior of handball players with non-athletes on both MOT and MIT. Since previous researchers have shown that MOT and MIT engage different eye movement strategies, we had participants track 3-5 targets among 10 moving objects. In MOT, the objects were identical, while in MIT they differed in shape and color. Although we observed no group differences for tracking accuracy, the eye movements of athletes were more target-oriented than those of non-athletes. We concluded that tasks and stimuli intended by researchers to demonstrate that athletes' show better object tracking than non-athletes should be specific to the athletes' type of sport and should use more perception-action coupled measures. An implication of this conclusion is that the differences in object tracking skills between athletes and non-athletes is highly specific to the skills demanded by the athletes' sport.

The Outcome of Arthroscopic Anterior Cruciate Ligament Reconstruction in Low-Demand, Non-athletic Patients Following a Home-Based Rehabilitation Protocol.

BACKGROUND: Arthroscopic anterior cruciate ligament (ACL) reconstruction is a common orthopedic procedure. Most of the literature is on high-demand athletic patients, with little information about the outcomes of low-demand patients. Therefore, we aim to assess the outcomes of non-athletic patients following home-based rehabilitation. METHODS: An observational cross-sectional comparative study was conducted with 30 non-athletic adults with ACL injuries whose pre-injury Tegner activity level was four or less. After six months of reconstruction, patients were assessed for functional outcomes using the Tegner activity level, Lysholm score, International Knee Documentation Committee (IKDC) score, and ACL quality of life (QOL) score. Functional performance was assessed by the carioca test, one-leg hop test, and shuttle test. Functional outcome and performance were compared with an age, sex, and activity level-matched group. Knee stability was assessed by Lachman, anterior drawer, and pivot shift. RESULTS: All patients returned to their pre-injury Tegner activity level. A statistically significant difference was seen in the Lysholm score, IKDC score, ACL QOL score, carioca test, shuttle test, and one leg hop test (p= <0.001 in each); >5mm of translation of the tibia in the Lachman test was seen in three patients, whereas one patient had >5 mm of translation in the anterior drawer test but pivot shift was absent in all. CONCLUSION: We found that all patients returned to their pre-injury Tegner activity level. Most patients had improved knee stability; however, functional outcomes and performance were lower compared to the control group. Therefore, arthroscopic ACL reconstruction is a reasonable treatment option for non-athletic, low-demand patients to get back to their pre-injury functional activity level.

Examining the ability to track multiple moving targets as a function of postural stability: a comparison between team sports players and sedentary individuals.

Background: The ability to track multiple objects plays a key role in team ball sports actions. However, there is a lack of research focused on identifying multiple object tracking (MOT) performance under rapid, dynamic and ecologically valid conditions. Therefore, we aimed to assess the effects of manipulating postural stability on MOT performance. Methods: Nineteen team sports players (soccer, basketball, handball) and sixteen sedentary individuals performed the MOT task under three levels of postural stability (high, medium, and low). For the MOT task, participants had to track three out of eight balls for 10 s, and the object speed was adjusted following a staircase procedure. For postural stability manipulation, participants performed three identical protocols (randomized order) of the MOT task while standing on an unstable platform, using the training module of the Biodex Balance System SD at levels 12 (high-stability), eight (medium-stability), and four (low-stability). Results: We found that the ability to track moving targets is dependent on the balance stability conditions (F2,66 = 8.7, p < 0.001, η² = 0.09), with the disturbance of postural stability having a negative effect on MOT performance. Moreover, when compared to sedentary individuals, team sports players showed better MOT scores for the high-stability and the medium-stability conditions (corrected p-value = 0.008, Cohen's d = 0.96 and corrected p-value = 0.009, Cohen's d = 0.94; respectively) whereas no differences were observed for the more unstable conditions (low-stability) between-groups. Conclusions: The ability to track moving targets is sensitive to the level of postural stability, with the disturbance of balance having a negative effect on MOT performance. Our results suggest that expertise in team sports training is transferred to non-specific sport domains, as shown by the better performance exhibited by team sports players in comparison to sedentary individuals. This study provides novel insights into the link between individual's ability to track multiple moving objects and postural control in team sports players and sedentary individuals.

The effect of impact exercise on bone mineral density: A longitudinal study on non-athlete adolescents.

PURPOSE: High impact exercise is known to induce osteogenic effects in the skeleton. However, less is known about the systemic effect of exercise practice in a potential adaptive mechanism of the skeletal accrual. This research aimed to assess the effect of impact exercise on bone mineral density (BMD) in the radius throughout adolescence. METHODS: This study evaluated 1137 adolescents, at 13 and 17 years old, as part of the population-based cohort EPITeen. BMD (g/cm2) was measured at the ultradistal and proximal radius of the non-dominant forearm by dual-energy X-ray absorptiometry (DXA) using a Lunar® Peripheral Instantaneous X-ray Image device. The practice of (extra-curricular) exercise was categorized as: no exercise, exercise with high impact and exercise with low impact. Regression coefficients (ß) and respective 95% confidence intervals (CI95%) were used to estimate the association between exercise practice categories at 13 years old and BMD at 13 and 17 years old and BMD gain between evaluations. RESULTS: In boys, at 13 years, BMD was similar between the ones not practicing exercise and those practicing exercise with low impact, and the gain of BMD was also similar in both groups. Still in boys, at 13 years, those who practiced exercise with high impact presented higher mean (standard-deviation) of BMD, comparing to the other two groups (no exercise and low impact exercise), and also significantly increased the BMD gain between 13 and 17 years (ß = 0.013; CI95%0.003;0.023). In girls, no statistically significant differences on BMD were found between the categories of exercise at 13 years and BMD at 17 years of age. CONCLUSION: This research shows that the practice of high impact exercise could help to increase BMD more than low impact exercise even in a nonweight-bearing bone during adolescence.

Disordered Eating Attitudes, Anxiety, Self-Esteem and Perfectionism in Young Athletes and Non-Athletes.

Eating disorders are associated with short and long-term consequences that can affect sports performance. The purposes of this study were to investigate whether female athletes, particularly gymnasts and footballers, exhibit more eating problems compared to female non-athletes, and to identify individual personality characteristics including anxiety, self-esteem, and perfectionism as possible contributors to eating disorder risk. In a sample of 120 participants, 80 adolescent female athletes were compared to a control condition of 40 non-athletes (mean age 17.2 ± 2.82). Participants responded to a questionnaire package to investigate the presence of disordered eating (SCOFF) and psychological variables in relation to disordered eating symptoms or eating disorder status. Subsequently, anthropometric measures were obtained individually by trained staff. There were statistically significant differences between conditions. One of the most important results was the score in SCOFF (Mann-Whitney = 604, p < 0.05; Cohen's d = 0.52, r = 0.25), being higher in control than in the gymnast condition. These results suggest that non-athlete female adolescents show more disturbed eating behaviours and thoughts than female adolescents from aesthetic sport modalities and, therefore, may have an enhanced risk of developing clinical eating disorders.

Risk for eating disorders and body composition among adolescent female and male athletes and non-athlete controls.

Purpose The objective of this research was to investigate the risk for eating disorders (EDs) and compare body composition in participants with and without risk in adolescent Slovenian athletes and aged matched controls. Methods A total of 583 randomly selected adolescents, aged from 15 to 17 years, completed a sick, control, one stone, fat, food (SCOFF) questionnaire for detecting risk for EDs. Weight and body composition were measured using a bioelectrical impedance machine. Based on the data body mass index (BMI), percentiles were calculated. Results Overall, 37.7% of athletes and 39.8% of controls were classified as at risk for EDs. Girls showed a significantly higher frequency of risk than boys, 1:3.5. A higher percentage of underweight boys was found in control group compared to the athletes, but the difference was not significant in the subsample of girls. Differences in body composition show that the at-risk group had significantly higher values in BMI percentiles (p < 0.001) and percentages of fat mass (p < 0.001) and lower values in percentage of muscle mass (p < 0.01) and fat-free mass. Conclusions These finding demonstrate that the gap in risk for EDs between males and females is becoming smaller and stresses to consider specific parameters of body composition as being important when identifying at-risk groups for EDs.

Effects of the movement velocity training on sprint performance / 体力科学

To investigate the effects of training focused on the movement velocity of the lower limbs (movement velocity training) on short sprint performance in young female non-athletes. Twenty-nine healthy young females (mean age: 20.1 ± 0.9 years) participated in this study. The subjects were randomized into a movement velocity training group (MV group, n=15) and a resistance training group (R group, n=14). MV group performed six lower limb exercises at high velocity (as fast as possible) with no load. R group performed five lower limb strength exercises using a resistance band. Both training programs were applied for 20 minutes per session, 5 days a week for 6 weeks. The following outcomes were measured at baseline and after 6 weeks of training: 30 m sprint time, 20- 26m running velocity, step length, step frequency, and muscle strength and movement velocity of knee extension. Significant group × time interactions were observed for the 30-m sprint time with the MV group exhibiting a significant improvement on simple main effect analysis. For the other parameters (step length, step frequency, and muscle strength and movement velocity of knee extension), group × time interactions were not observed and a significant main effect was observed. These findings suggest that training focused on the movement velocity of the lower limbs can be effective for improving sprint performance.

Visual Reaction Time And Visual Anticipation Time Between Athletes And Non-Athletes

@#An experimental investigation was conducted to explore visual reaction time and visual anticipation time between athletes and non-athletes. These visual perceptual skills form the base for cognitive processes required by the brain to respond instantaneously to a stimulus. A total of 228 adolescents, equally distributed between athletes and non-athletes, aged 13 to 16 years (mean age 14.69 ± 0.99 years) were examined. The visual reaction time and visual anticipation time were measured using a Lafayette Reaction Timer (Model 63035) and Bassin Anticipation Timer (Model 35575) respectively. The visual reaction time results revealed that athletes have faster reaction time scores as compared to non-athletes, whereas with visual anticipation time, athletes had fewer errors and a higher consistency compared to non-athletes. There was, however, no interaction between gender and sports participation noted for both these visual perceptual skills. These research findings indicate that gender was not an obstacle in sports participation, therefore not limiting the potential to excel in sports performance. Knowledge gained from these research findings will benefit the sports industry, specifically in athletic and sports training as well as provide a basis for the identification of an individual’s potential in their sports.

Physiological Tendon Thickness Adaptation in Adolescent Elite Athletes: A Longitudinal Study.

Increased Achilles (AT) and Patellar tendon (PT) thickness in adolescent athletes compared to non-athletes could be shown. However, it is unclear, if changes are of pathological or physiological origin due to training. The aim of this study was to determine physiological AT and PT thickness adaptation in adolescent elite athletes compared to non-athletes, considering sex and sport. In a longitudinal study design with two measurement days (M1/M2) within an interval of 3.2 ± 0.8 years, 131 healthy adolescent elite athletes (m/f: 90/41) out of 13 different sports and 24 recreationally active controls (m/f: 6/18) were included. Both ATs and PTs were measured at standardized reference points. Athletes were divided into 4 sport categories [ball (B), combat (C), endurance (E) and explosive strength sports (S)]. Descriptive analysis (mean ± SD) and statistical testing for group differences was performed (α = 0.05). AT thickness did not differ significantly between measurement days, neither in athletes (5.6 ± 0.7 mm/5.6 ± 0.7 mm) nor in controls (4.8 ± 0.4 mm/4.9 ± 0.5 mm, p > 0.05). For PTs, athletes presented increased thickness at M2 (M1: 3.5 ± 0.5 mm, M2: 3.8 ± 0.5 mm, p < 0.001). In general, males had thicker ATs and PTs than females (p < 0.05). Considering sex and sports, only male athletes from B, C, and S showed significant higher PT-thickness at M2 compared to controls (p ≤ 0.01). Sport-specific adaptation regarding tendon thickness in adolescent elite athletes can be detected in PTs among male athletes participating in certain sports with high repetitive jumping and strength components. Sonographic microstructural analysis might provide an enhanced insight into tendon material properties enabling the differentiation of sex and influence of different sports.

Visual efficiency among teenaged athletes and non-athletes.

AIM: To compare visual efficiency, specifically accom-modation, vergence, and oculomotor functions among athletes and non-athletes. METHODS: A cross-sectional study on sports vision screening was used to evaluate the visual skills of 214 elementary students (107 athletes, 107 non-athletes), aged between 13 and 16y. The visual screening assessed visual parameters such as ocular motor alignment, accommodation, and vergence functions. RESULTS: Mean visual parameters were compared between age-group matched athletes (mean age 14.82±0.98y) and non-athletes (mean age 15.00±1.04y). The refractive errors of all participants were corrected to maximal attainable best corrected visual acuity of logMAR 0.0. Accommodation function assessment evaluated amplitude of accommodation and accommodation facility. Vergence functions measured the near point of convergence, vergence facility, and distance fusional vergence at break and recovery point. Ocular motor alignment was not statistically significant between both groups. Athletes had a statistically significant amplitude of accommodation for both the right eye (t=2.30, P=0.02) and the left eye (t=1.99, P=0.05). Conversely, non-athletes had better accommodation facility (t=-2.54, P=0.01) and near point of convergence (t=4.39, P<0.001) when compared to athletes. Vergence facility was found to be better among athletes (t=2.47, P=0.01). Nevertheless, non-athletes were significantly better for both distance negative and positive fusional vergence. CONCLUSION: Although the findings are still inconclusive as to whether athletes had superior visual skills as compared to non-athletes, it remains important to identify and elucidate the key visual skills needed by athletes in order for them to achieve higher performance in their sports.

Comparison of disordered eating symptoms and emotion regulation difficulties between female college athletes and non-athletes.

The purpose of the study was to compare the prevalence of disordered eating between female college athletes and non-athletes and explore emotion regulation as a potential mediator of the link between participation in athletics and disordered eating symptoms. Data for this cross-sectional study came from 527 college students in a mid-western state of the USA in fall of 2013 (376 non-athletes and 151 athletes). Disordered eating symptoms and emotion regulation were assessed utilizing the Eating Attitudes Test and the Difficulties with Emotion Regulation Scale in a survey-based format. The prevalence of disordered eating was higher in non-athletes (16.5%, vs. 6.6%; X(2)=62.8; p<.05). Non-athletes reported more signs and symptoms of disordered eating than athletes (p<.01). A linear regression approach indicated a statistically significant indirect effect (0.63, CI95=0.18, 1.20) of athletic-status on disordered eating via emotion regulation; however, this effect did not reach practical significance. Our findings show that female athletes in our sample were somewhat protected from disordered eating compared to non-athletes, but the mechanism of this relationship is unclear. A further in-depth examination of other factors, such as self-esteem and body satisfaction, that may have contributed to this finding is warranted utilizing a large sample of female college students and athletes representing a variety of sports.

Adolescent elite athletes' cigarette smoking, use of snus, and alcohol.

The purpose was to examine cigarette smoking, use of snus, alcohol, and performance-enhancing illicit drugs among adolescent elite athletes and controls, and possible gender and sport group differences. First-year students at 16 Norwegian Elite Sport High Schools (n = 677) and two randomly selected high schools (controls, n = 421) were invited to participate. Totally, 602 athletes (89%) and 354 (84%) controls completed the questionnaire. More controls than athletes were smoking, using snus, and drinking alcohol. Competing in team sports was associated with use of snus [odds ratio = 2.8, 95% confidence interval (CI) 1.6 to 4.7] and a similar percentage of male and female handball (22.2% vs 18.8%) and soccer players (15.7% vs 15.0%) reported using snus. For controls, not participating in organized sport was a predictor for smoking (odds ratio = 4.9, 95% CI 2.2 to 10.9). Female athletes were more prone to drink alcohol than males (46.3% vs 31.0%, P < 0.001). Only, 1.2% athletes and 2.8% controls reported use of performance-enhancing illicit drugs. In conclusion, use of legal drugs is less common among athletes, but this relationship depends on type of sport and competition level. The association between team sports and use of snus suggests that sport subcultures play a role.

Arterial blood pressure in female students before, during and after exercise.

BACKGROUND: Physical activity (PA) has been associated with reduced blood pressure in observational epidemiologic studies and individual clinical trials. Since PA is considered as a key component for the prevention and treatment of hypertension in children and adolescents, the purpose of this study was to assess blood pressure changes in athletic and non-athletic students before, during and after PA. METHODS: The subjects in this experimental study consisted of 60 female athletic (n = 30) and non-athletic students (n = 30) with an average age of 21-23 years. The athletes were physical education students and non-athletes were medical students. Blood pressure (BP) at the right arm was measured in sitting position at 5 minutes before, 6 minutes after starting PA and 5 minutes after the end of the exercise. Weight, height, body mass index (BMI), mean arterial pressure (MAP) and pulse pressure (PP) were measured by ordinary methods. Data was analyzed using student's t- test. Results were expressed as mean ± SD. The statistical difference was considered significant at P < 0.05. RESULTS: The results showed that while systolic BP (SBP) increased during and 5 minutes after the end of physical exercise in both groups, diastolic BP (DBP) decreased. However, SBP values were significantly lower in non-athletic female students compared to the athletes. On the other hand, DBP values were significantly lower in athletic female students compared to non-athletes. Moreover, heart rate values were significantly lower at rest, during and 5 minutes after the end of physical exercise in athlete female students compared to non-athletes. CONCLUSION: Our results revealed that physical activity reduced arterial BP levels in female athlete students.

Intra-familial transmission of Trichophyton tonsurans / 대한의진균학회지

Trichophyton(T.) tonsurans was an anthropophilic dermatophyte and has not been prevalent in Korea yet. Especially the infection of non-athletic patient was very rare and only 7 cases have been reported so far in Korea. We report 1 case of tinea capitis and 2 cases of tinea faciei due to T. tonsurans in a family, i.e grandfather, grandmother and grandson. Grand father and grand mother had pruritic scaly erythematous macule on their face and grandson had a 10 x 10 cm sized alopecia with black dots on the scalp. We confirmed T. tonsurans in all cases based on the microscopic findings and fungal culture. Although we could not confirm the source and the exact transmission route, these patients are not athletes and none of them had contact history with any athletes. So we think that T. tonsurns might have been already spreading among general population of Korea.