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81.
The purpose of this study was to explore the effects of the perceived purpose of exercising on the self-selected distance peddled during an acute cycling task. Participants were randomly assigned to one of three groups (health, wealth, charity). All participants watched a video emphasizing the health benefits of performing at least 30?min of daily exercise. Those in the health group were not provided any additional information. Those in the wealth group were then informed that they would earn money for every two kilometres cycled. Those in the charity group were informed that they would earn money for a charity for every two kilometres cycled. Participants were not given a time/distance limit and were instructed to cycle until they chose to stop. Analyses revealed that participants in the wealth and charity group cycled significantly farther than those in the health group (approximately twice as far). Additionally, a significant sex by group interaction showed that women cycled farther for charity while men cycled farther for wealth. These results suggest that health messages used to increase exercise behaviour may benefit from exploring how paradigms from behavioural economics influence behaviors that have relevance to public health.  相似文献   
82.
This study investigated the associations between fundamental athletic movement and physical fitness in junior Australian football (AF). Forty-four under 18 players performed a fundamental athletic movement assessment consisting of an overhead squat, double lunge, single leg Romanian deadlift and a push up. Movements were scored on three assessment criterions using a three-point scale. Additionally, participants performed five physical fitness tests commonly used for talent identification in AF. A Spearman’s nonparametric correlation matrix was built, with correlation coefficients being visualised using a circularly rendered correlogram. Score on the overhead squat was moderately positively associated with dynamic vertical jump height on left (rs = 0.40; P ≤ 0.05) and right (rs = 0.30; P ≤ 0.05) leg take-off, stationary vertical jump (rs = 0.32; P ≤ 0.05) and negatively associated with 20-m sprint time (rs = ?0.35; P ≤ 0.05). Score on the double lunge (left/right side) was moderately positively associated with the same physical fitness tests as well as score on the multistage fitness test. Results suggest that improvements in physical fitness qualities may occur through concurrent increases in fundamental athletic movement skill, namely the overhead squat and double lunge movements. These findings may assist with the identification and development of talent.  相似文献   
83.
This study quantified lower-limb strength decrements and assessed the relationships between strength decrements and performance fatigue during simulated basketball. Ten adolescent, male basketball players completed a circuit-based, basketball simulation. Sprint and jump performance were assessed during each circuit, with knee flexion and extension peak concentric torques measured at baseline, half-time, and full-time. Decrement scores were calculated for all measures. Mean knee flexor strength decrement was significantly (P < 0.05) related to sprint fatigue in the first half (R = 0.65), with dominant knee flexor strength (R = 0.67) and dominant flexor:extensor strength ratio (R = 0.77) decrement significantly (< 0.05) associated with sprint decrement across the entire game. Mean knee extensor strength (R = 0.71), dominant knee flexor strength (R = 0.80), non-dominant knee flexor strength (R = 0.75), mean knee flexor strength (R = 0.81), non-dominant flexor:extensor strength ratio (R = 0.71), and mean flexor:extensor strength ratio (R = 0.70) decrement measures significantly (P < 0.05) influenced jump fatigue during the entire game. Lower-limb strength decrements may exert an important influence on performance fatigue during basketball activity in adolescent, male players. Consequently, training plans should aim to mitigate lower-limb fatigue to optimise sprint and jump performance during game-play.  相似文献   
84.
Whilst previous research has highlighted significant relationships between golfers’ clubhead velocity (CHV) and their vertical jump height and maximum strength, these field-based protocols were unable to measure the actual vertical ground reaction force (vGRF) variables that may correlate to performance. The aim of this study was to investigate relationships between isometric mid-thigh pull (IMTP), countermovement jump (CMJ), squat jump (SJ) and drop jump (DJ) vGRF variables and CHV in highly skilled golfers. Twenty-seven male category 1 golfers performed IMTP, CMJ, SJ and DJ on a dual force platform. The vertical jumps were used to measure positive impulse during different stretch-shortening cycle velocities, with the IMTP assessing peak force (PF) and rate of force development (RFD). Clubhead velocity was measured using a TrackMan launch monitor at a golf driving range. Pearsons correlation coefficient analyses revealed significant relationships between peak CHV and CMJ positive impulse (r = 0.788, < 0.001), SJ positive impulse (r = 0.692; < 0.001), DJ positive impulse (r = 0.561, < 0.01), PF (r = 0.482, < 0.01), RFD from 0–150 ms (r = 0.343, < 0.05) and RFD from 0–200 ms (r = 0.398, < 0.05). The findings from this investigation indicate strong relationships between vertical ground reaction force variables and clubhead velocity.  相似文献   
85.
86.
社会体育概念管窥   总被引:11,自引:2,他引:11  
回顾了“社会体育”一词的由来及其在日本产生及发展的过程。论述了“群众体育”一词在我国出现的时代背景及其发展、演变的过程以及其与“社会体育”的关系,进而对“社会体育”的概念进行了定义。  相似文献   
87.
妈妈把我塞进被窝.妈妈,真的要下雪吗?她把毯子一直拉到我的下巴,在我脸上亲了一下.天气预报是这样说的.  相似文献   
88.
Translating relationship boundaries conceptualizations to the study of sibling relationships, this study examined the utility of sibling enmeshment and disengagement in predicting child adjustment difficulties in a sample of 282 mothers and adolescents (mean age = 12.7 years). Mothers completed a semistructured interview at the first measurement occasion to assess sibling interaction patterns. Adolescents, mothers, and teachers reported on children’s adjustment problems across 2 annual waves of assessment. Supporting the incremental utility of a boundary conceptualization of sibling relationships, results of latent difference score analyses indicated that coder ratings of sibling enmeshment and disengagement uniquely predicted greater adolescent adjustment difficulties even after taking into account standard indices of sibling relationship quality (i.e., warmth and conflict) and sibling structural characteristics (e.g., sex).  相似文献   
89.
BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease.  相似文献   
90.
基于移动学习的大学英语写作翻转教学,从设计到实践整个过程,是一种行之有效的教学模式。实践研究发现,移动信息技术为大学英语的翻转教学活动提供了个性化、协作式学习环境,使不同学习程度的学生能够打破学习时空界限,激发了学生英语写作学习动机和实践热情,使他们能积极有效地内化所学的知识和技能,提高英语写作教学的有效性,从而提高大学英语写作的教学质量。  相似文献   
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