Monitoring of immunological parameters in adolescent basketball athletes during and after a sports season     

Diego Trevisan Brunelli  Ariel Rodrigues  Wendell Arthur Lopes  Arthur Fernandes Gáspari  Valéria Bonganha  Paulo César Montagner 《Journal of sports sciences》2013,31(11):1050-1059

Abstract

The objective of the present study was to monitor the immunological and hormonal responses and the occurrence of upper respiratory symptoms in adolescent basketball athletes during the different stages of a sports season. Anthropometric measures, biochemical analyses (interleukin-6, interleukin-10, tumour necrosis factor-alpha, C-reactive protein, testosterone and cortisol), neuromuscular evaluations (standing vertical jumping ability, agility and estimated VO_2max) and leukocyte counts were performed at four moments: 72 h before the season (?72 h); before the season (Pre-season); after six weeks, at the end of the preparatory period (Preparatory); and after 20 weeks, at the end of the competitive period (Competitive). Also, the occurrence of upper respiratory symptoms was collected weekly during all stages of the season. There were significant increases in monocytes, cortisol, tumour necrosis factor-alpha and C-reactive protein at the Competitive moment as compared to the Pre-season. In addition, interleukin-10 decreased at the Competitive moment as compared to the Pre-season. Occurrence of upper respiratory symptoms demonstrated increases (38%) during the competitive period as compared to the preparatory. These results suggest that periods of training and competition could increase the occurrence of upper respiratory symptoms in adolescent athletes and this may be due to the unwanted effects of an inflammatory process in response to the excessive stress of training and competition.  相似文献   

Impact of the choice of threshold on physical activity patterns in free living conditions among adolescents measured using a uniaxial accelerometer: The HELENA study     

Jeremy Vanhelst  Laurent Béghin  Julia Salleron  Jonathan R. Ruiz  Francesco B Ortega  Charlene Ottevaere 《Journal of sports sciences》2013,31(2):110-115

Abstract

The aim of this study was to assess the impact of the choice of threshold on physical activity patterns measured in adolescents under free living conditions (FLC) using a uniaxial accelerometer. The study comprised 2043 adolescents (12.5–17.5 years) participating in the HELENA Study. Participants wore a uniaxial accelerometer for 7 days. The PA patterns were assessed using thresholds determined from six different studies. For each of the thresholds used, the number of adolescents fulfilling the recommendation of 60 min of moderate to vigorous PA (MVPA) per day was also calculated. A significant difference was found between thresholds regardless of the activity level: differences of 38%, 207%, 136%, and 2780% for sedentary, light, moderate, and vigorous intensity PA, respectively (P < 0.001). Time of MVPA varied between methods from 25.3 to 55.2 min · day^–1. The number of adolescents fulfilling the recommendation varied from 5.9% to 37% according to the thresholds used. The kappa coefficient for concordance in the assessment of the number of adolescents achieving the PA recommendations was generally low. The definition of the threshold for PA intensity may considerably affect the PA patterns in FLC when assessed using a uniaxial accelerometer and the number of participants fulfilling the recommendations.  相似文献   

Aerobic plus resistance training was more effective in improving the visceral adiposity,metabolic profile and inflammatory markers than aerobic training in obese adolescents     

Ana Raimunda Dâmaso  Danielle Arisa Caranti  Aline de Piano  Mauro Fisberg  Denis Foschini 《Journal of sports sciences》2013,31(15):1435-1445

Abstract

The purpose of this study was to determine whether aerobic plus resistance training (AT + RT) is more effective than aerobic training (AT) at reducing inflammatory markers and cardiovascular risk in obese adolescents. A total of 139 obese adolescents were enrolled, aged 15–19 years, body mass index (BMI) ≥ 95th percentile and participated in 1 year of interdisciplinary intervention. They were randomised into two groups: AT (n = 55), AT + RT (n = 61). Blood samples were collected to analyse glycaemia, insulin, the lipid profile, leptin and adiponectin concentrations. Insulin resistance was measured by homeostasis model assessment of insulin resistance index (HOMA-IR). The AT + RT group showed better results with regard to decreased body fat mass, low-density lipoprotein concentration (LDL-c) levels, subcutaneous and visceral fat and increased body lean mass. Indeed, a reduction of hyperleptinaemia and an increase in adiponectin concentrations, promoting an improvement in the leptin/adiponectin ratio, was observed. Important clinical parameters were improved in both types of exercise; however, AT + RT was more effective in improving the visceral adiposity, metabolic profile and inflammatory markers than AT alone, suggesting clinical applications for the control of intra-abdominal obesity and cardiovascular risk in the paediatric population.  相似文献   

Physiological Profiles of High School Female Cross Country Runners     

Nancy Kay Butts 《Research quarterly for exercise and sport》2013,84(1):8-14

Abstract

Percent body fat, ratings of perceived exertion and maximal oxygen consumption during a continuous running treadmill test were obtained on 127 high school female cross country runners. These young runners (x 15.6 yrs) were running approximately 25 miles per week at the time of testing. They had an average [Vdot]O₂ max of 50.8 ml · min^-1 and an HR max of 198.0 bpm. The mean percent body fat, as determined from hydrostatic weighing, was 15.4%. The onset of metabolic acidosis was estimated to occur at 78% of [Vdot]O₂ max. A stepwise multiple regression with the 3000 meter run as the dependent variable indicated that max treadmill run time, weight relative [Vdot]O₂ max and [Vdot] max entered the equation in that order, yielding an R of 0.67. Both HR and RPE increased with work intensity, but not at equal rates. These high school female runners had higher [Vdot]O₂ max's than previously reported for this age group; however, they were considerably below these values reported for national caliber distance runners.  相似文献   

The Nature,Occurring Contexts,and Psychological Implications of Weight-Related Teasing in Urban Physical Education Programs     

Weidong Li  Paul Rukavina 《Research quarterly for exercise and sport》2013,84(2):308-317

This study examined the nature, occurring contexts, and psychological implications of weight-related teasing in urban physical education programs. Semistructured interviews were conducted with 47 participants from a large urban school district. Data were analyzed using inductive analysis and constant comparisons. Most overweight adolescents experienced many different types of teasing in physical education. Victims of teasing felt hurt and experienced uncomfortable feelings due to social comparisons. Overweight students who were not teased reported a variety of reasons. Teachers lacked awareness of and strategies to handle teasing of overweight students. There is a need to implement preventive policies and rules to eliminate weight-related teasing and create inclusive physical education environments.  相似文献   

构建青少年体质健康与体育公共信息服务平台的研究     

杜芸芸 《安徽体育科技》2013,34(2):1-3

分析了构建青少年体质健康与体育公共信息服务平台的现实意义,论述了构建青少年体质健康与体育公共信息服务平台的途经、功能模块的划分、实现的技术手段等内容,阐明了其可以发挥的作用。  相似文献   

Development of a Questionnaire Assessing School Physical Activity Environment     

Jennifer Robertson-Wilson  Lucie Lévesque  Ronald R. Holden 《Measurement in physical education and exercise science》2013,17(2):93-107

This study was designed to develop the Questionnaire Assessing School Physical Activity Environment (Q--SPACE) based on student perceptions. Twenty-eight items rated on 4-point Likert scales were administered to 244 middle school students in 9 schools. Exploratory factor analysis was used to evaluate the underlying structure of the items and 2 factors were extracted: physical environment (PE) and social environment (SE). Twelve and 8 items loaded saliently on PE (e.g., gym classes available) and SE (e.g., teacher encouragement), respectively. Factor scales had alpha coefficients of .86 (PE) and .81 (SE). One-week test–retest reliabilities for the factor scales of PE and SE were .78 and .72, respectively. Differences in PE scale scores across schools and PE and SE scale scores across student school physical activity behavior (e.g., participation on school teams) provided some evidence of scale construct validity. Overall, Q–SPACE demonstrates acceptable reliability for capturing middle school students' perceptions of school physical activity environment. The factorial validity needs to be assessed with confirmatory factor analysis and invariance testing procedures.  相似文献   

Countermovement jump in performance diagnostics: Use of the correct jumping technique     

《European Journal of Sport Science》2013,13(3):231-237

Abstract

The aim of this study was to examine the effects of arm-swing and sporting activity on jump height and jump height variability of countermovement jumps in adolescent students to inform correct jumping technique in different settings. Altogether, 324 students (grades 5–11) performed three countermovement jumps with bilateral arm-swings and three countermovement jumps without arm-swings on a force platform. The participants were divided into three groups based on sporting activity. The groups with the most (“active group”; more than 6 h formal athletics in a sport club per week) and least active (“sedentary group”; less than 3 h formal athletics in a sport club per week) participants were compared. Jump height was calculated for all jumps, and the best trial of three was used for further analysis. Jump height variability was indicated by the coefficient of variation over three jumps. The reliability of jump height was determined using the intra-class correlation coefficient (ICC) over three trials of each jumping technique. The reliability of jump height was very high for all conditions (ICC: 0.90–0.96). Jump height was significantly higher for countermovement jumps with than without arm-swings for both groups. Jump height in the active group was significantly greater than in the sedentary group for both jumping techniques. A significant interaction between jumping technique and sporting activity indicates a greater benefit of arm-swing in the active than in the sedentary participants. No significant differences between groups were observed for jump height variability. Jump height can be measured reliably in active and sedentary adolescent individuals for both jumping techniques. The relevant jumping technique should be chosen with respect to the context of its application and based on its suitability for the individual and task of interest.  相似文献   

Cross-sectional and longitudinal relationship between physical fitness and academic achievement in Japanese adolescents     

《European Journal of Sport Science》2013,13(9):1240-1249

Abstract

Although cross-sectional studies regarding the relationship between physical fitness and academic achievement among Japanese children have been previously reported, no longitudinal study has yet been reported for Japanese children. The purpose of this study was to examine the cross-sectional and longitudinal relationships between physical fitness and academic achievement among Japanese adolescents. This cohort study included 1,189 seventh- and ninth-grade students from two schools. The follow-up period was 2 years. A physical fitness test involving eight test items (hand grip, sit-ups, sit and reach, side-to-side jump, 20-m shuttle run, 50-m dash, standing broad jump and handball throwing) was conducted to evaluate the fitness of the participants. Academic achievement in Japanese, mathematics and a foreign language (English) was assessed at baseline and follow-up using cumulative guidance records. Participants were classified into low–low, high–low, low–high, and high–high groups based on physical fitness test results at baseline and follow-up. Compared with the groups showing low fitness levels, those showing high fitness levels for all items of the physical fitness test expect handball throwing had increased odds of showing high academic achievement levels in all three subjects at baseline and/or follow-up compared with the low-fitness groups. Sit-ups and 20-m shuttle run in the high–high and low–high groups were related to higher academic achievement levels at follow-up compared with those in the low–low group for both boys and girls. Therefore, this study suggests that various physical fitness outcomes are positively associated with high academic achievement levels for Japanese children.  相似文献   

高中体育考试改革探析——增强青少年体质的对策研究     

付慧宇  张景华  刘浩 《天津体育学院学报》2012,27(3):275-276

2006年,教育部提出:每天锻炼一小时,健康工作五十年,幸福生活一辈子。实施包括德智体在内的素质教育是我国提高国民素质的战略举措。增强青少年体质,促进青少年健康成长,不仅关系着青少年及其家庭的幸福,且关系我国人才培养的质量和整个中华民族的健康。2007年,《中共中央国务院关于加强青少年体育增强青少年体质的意见》明确提出:认真落实健康第一的指导思想,把增强学生体质作为学校教育的基本目标之一。1我国青少年学生体质和健康现状1.1我国青少年学生体能素质呈下降趋势1985年开始,教育部、国家体育总局、卫生部等联手每5年对我国多民族学生体质和健康进行调研,结果显示:我国青少年学生  相似文献