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1.
Abstract

The purpose of this study was to assess the potential influence of birth quarter on the frequency of physical activity and participation in specific activities during adulthood. We used data from one national and one provincial survey, the 2005 Canadian Community Health Survey and the 1998 Quebec Social and Health Survey (Enquête sociale et de santé du Québec) respectively. We analysed the distribution of participants at each level of practice of a given leisure activity and work-related physical activity. In the Canadian Community Health Survey, a relative age effect was found for participation in soccer in the 25- to 60-year-old population. However, for volleyball, a significant relative age effect was also observed but with over-representation of the last quarters of the year for the whole population and for men aged 12–60 years. In the Quebec Social and Health Survey, significant differences in the frequency of distribution without a relative age effect were revealed for participation in women's ice hockey, work-related physical activity level, and stage of change for physical activity. Overall, the data indicate that the systematic relative age effect reported in other studies for some competitive sports, such as ice hockey and soccer, is not as prevalent in leisure physical activities during adulthood. This may reflect lower competitive selection and attrition in population physical activity compared with competitive sports in younger athletes.  相似文献   

2.
Abstract

Previous work on dynamics of interpersonal interactions in 1 vs. 1 sub-phases of basketball has identified changes in interpersonal distance between an attacker and defender as a potential control parameter for influencing organizational states of attacker–defender dyads. Other studies have reported the constraining effect of relative velocity between an attacker and defender in 1 vs. 1 dyads. To evaluate the relationship between these candidate control parameters, we compared the impact of both interpersonal distance and relative velocity on the pattern-forming dynamics of attacker–defender dyads in the sport of rugby union. Results revealed that when interpersonal distance achieved a critical value of less than 4 m, and relative velocity values increased or were maintained above 1 m · s?1, a successful outcome (i.e. clean attempt) for an attacker was predicted. Alternatively, when values of relative velocity suddenly decreased below this threshold, at the same critical value of interpersonal distance, a successful outcome for the defender was predicted. Data demonstrated how the coupling of these two potential, nested control parameters moved the dyadic system to phase transitions, characterized as a try or a tackle. Observations suggested that relative velocity increased its influence on the organization of attacker–defender dyads in rugby union over time as spatial proximity to the try line increased.  相似文献   

3.
Introduction: Many studies in physical education (PE) have sought to identify and categorize the modes of student interaction in order to gain greater insight into the nature of cooperative activity. More others recent studies have examined how modes of interaction evolve on the basis of the modes of collective activity that they generate. These studies have shown to describe and explain the interactions among individuals and the processes they generate, which then lead to the construction, deconstruction or reconstruction of different interaction modes. Although some studies have sought to describe the dynamics of student interactions, very few have quantified these dynamics. By doing so, however, researchers might gain a new perspective on student interaction modes that inspires new designs for teaching in PE, thereby having professional impact. The present study extends this research by investigating the dynamics of student interaction, with a focus on the emergence of interaction modes during orienteering lessons. For this purpose, the study was conducted within the methodological framework of course of action theory, which is an effective approach for examining activity in natural situations to provide insight into the experience of activity from the actors perspective.

Method: The study was conducted in two classes of seventh-grade students (about 12 years old) in which 16 students volunteered and were available for post-action interviews immediately after the lessons under study. These volunteers were placed in eight affinity-based dyads. The teachers planned orienteering lessons at similar levels of difficulty and duration but modified the lessons across a range of contextual features. Two categories of data were collected: (1) data from audiovisual recordings as the students searched for the checkpoints and (2) verbalization data during the post-action interviews with the students. The data were processed in two steps: one qualitative, the other quantitative. The qualitative step consisted of processing the data of the student experiences to characterize their interactions in the three different contexts. In the quantitative step, the data from the first step were graphically represented to depict the interaction dynamics within the student dyads.

Results and discussion: The qualitative analysis showed the emergence of three modes of student interaction shared across each learning context: co-construction, confrontation and delegation. The quantitative analysis revealed the percentages of the different modes of interaction and therefore characterized the interaction dynamics. Our results showed that the interaction dynamics within the dyads were both unique and similar in the task contexts in terms of both ratios of change and distribution. Results are discussed across two major points of interest: (1) the observation of the same interaction modes whatever the context yet with quite different dynamics and (2) proposals for PE teacher interventions.  相似文献   


4.
ABSTRACT

The objective of this study was to determine the effect of Kinesio Taping (KT), alone or together with balance exercises (BE), on parameters related to postural control, such as dynamic balance, static balance and flexibility. Forty-four male amateur soccer players (mean age 24.45 (4.79) years) were randomly allocated to 3 groups: KT+BE that received KT and BE (n = 16); KTp+BE, in which the KT was used as a placebo (n = 15) and KT alone (n = 13). The intervention period lasted 4 weeks. Star Excursion Balance Test (SEBT), Unipedal Stance Test (UST) and the Toe Touch Test (TTT) were assessed at baseline (pre), two weeks after beginning the treatment (mid) and after the intervention (post). We observed a significant improvement on the SEBT (mid and post-treatment) and the UST (post-treatment), but not on the TTT in either KT+BE or KTp+BE groups post treatment. No differences were found either in KT group at any time point or between groups in any variable studied. In conclusion, KT functional correction technique does not improve static and dynamic balance when applied alone, whereas BE alone or combined with KT significantly improves these variables. None of these techniques has any effect on flexibility.

Abbreviation: KT: Kinesiotaping; BE: Balance exercises; KTp: Placebo Kinesiotaping; UST: Unipedal Stance Test; SEBT: Star Excursion Balance Test; TTT: Toe Touch Test  相似文献   

5.
Abstract

In order to investigate the effects of modeling behavior for seven- and nine-year-old children, 30 seven-year-old and 30 nine-year-old females were randomly assigned within age level to three groups. These groups differed according to whether a model was presented at the beginning, midway, or not at all during 12 trials on the stabilometer. Both age groups were found to be similar in performance in the no model condition and, for both age groups, the beginning model condition was found to facilitate performance. However, the introduction of the model after six trials had a detrimental effect on the performance of younger children but facilitated older children's performance. These findings were interpreted in light of a likely increase in the processing capacity of nine year olds as well as an increase in the number of movement schemes that were previously stored in the older girls.  相似文献   

6.
Abstract

Forty-two underachieving grade 1 children matched for age, sex, IQ, and Lee-Clark reading grade level were randomly assigned to one of three groups. One group received perceptual-motor training, the second received exercises from the regular physical education curriculum, and the third group served as a control. After seven weeks of training (two periods a week) reading achievement was reassessed. The experimental group was found to have made statistically significant gains, while the other two groups had made no such gains.  相似文献   

7.
8.
Abstract

The aims of this study were to test for the presence of a relative age effect among male (n = 119,715) and female (n = 12,823) members of the shooting sports federation, and to determine whether any such effect has an impact on dropout from the sport. For the boys and girls, the results show a uniform distribution of dropout. A relative age effect was not found for the girls, showing that in female shooting sports there is no such effect. For the males, a significant statistical relative age effect was not detected in the 18–20 and 13–14 year categories. However, a relative age effect was found among adults and the 11–12 and under 11 year categories. A significant “inverse” relative age effect was found for the 15–17 year group. Further qualitative research is needed to clarify which factors contribute to this asymmetric distribution of birth dates in French male shooting sports.  相似文献   

9.
Abstract

This study determined whether precooling would have an additive effect on repeat-sprint cycling performance in heat following partial acclimation. Ten males completed three trials; Pre Acclimation (Pre Acc) and two Post Acclimation trials, one with precooling (ice jacket and slushy; Post Acc +PC) and another without (Post Acc). Trials consisted of a 30-min baseline period followed by a 70-min repeat-sprint protocol in ~35°C and 60% relative humidity. Separating pre and post trials were five heat acclimation sessions. Although no significant differences were found for performance variables, inferential statistical analysis resulted in moderate effect sizes, which suggested more work (J · kg?1) was performed in Post Acc compared with Pre Acc. Further, ‘possible’ and ‘very likely’ benefits were found for every performance variable for Post Acc compared with Pre Acc, while ‘possible’ benefits were found for Post Acc, compared with Post Acc +PC, for peak power output (W and W · kg?1). Moderate to strong effect sizes suggested lower core temperatures in both post acclimation trials compared with Pre Acc. Sweat loss was significantly higher (P < 0.05; 23.1%) in Post Acc +PC compared to other trials. In conclusion, no additional performance enhancement was seen when partially acclimated individuals precooled prior to repeat-sprint performance in heat.  相似文献   

10.
Abstract

The birth date distributions of elite male and female footballers in Australia, from junior youth (age 14 and upwards) to senior (professional) players, were examined. A statistically significant relative age effect was found among junior male players, reducing in effect with increasing age. An inter-year relative age effect that became apparent among the players at national level in the Under-17 and Under-20 age groups, due to the timing of the respective World Cups for those age groups, was also identified. It is conjectured that this might lead to players born in certain years having a curtailed pathway in the elite game, leading to drop-out among this very elite group. In the case of women elite players, no significant relative age effect was found among youth players, possibly due to less fierce competition for places, although a significant effect was found to exist at senior elite level.  相似文献   

11.
PurposeThe purpose of this study was to compare established methods with newly-developed methods for estimating the total energy expenditure (TEE).MethodsThe study subjects comprised 46 individuals, including 16 middle-aged men (mean age 51.4 years), 14 middle-aged women (mean age 49.9 years) and 16 young women (mean age 19.1 years). The TEE was estimated from 24-h heart rate (HR) data using newly-developed software (MoveSense HRAnalyzer 2011a, RC1, Suunto Oy, Vantaa, Finland), and was compared against the TEE determined using doubly labeled water (DLW). Agreement between the two methods was analyzed using Bland and Altman plots.ResultsThe HR method yielded similar TEE values as the DLW method at the group level, with an average of 8.6 kcal/day in the difference in the mean, but with large individual variations. Forty-four (96%) out of 46 subjects fell within ±2SD of the mean difference in TEE comparisons, and there was no tendency towards under- or over-estimation.ConclusionOur results indicate that the current software using HR analysis for the estimation of daily TEE needs further development for use with free-living individuals.  相似文献   

12.
Abstract

This study examined the effect of two different interval training programs–high-intensity interval training (HIT) and supramaximal interval training (SMIT)–on measures of sprint and endurance performance. Physically active individuals (Females: n=32; age 19.3, s=2.2 years; mass 67.6, s=9.1 kg; stature 172.7, s=6.6 cm. Males: n=23; age 20.0, s=2.7 years; mass 71.3, s=8.3 kg; stature 176.6, s=5.8 cm) completed pre-testing that comprised (1) 3000 m time-trial, (2) 40 m sprint, and (3) repeated sprint ability (RSA–6×40 m sprints, 24 s active recovery) performance. Participants were then matched for average 3000 m running velocity (AV) and randomly assigned to one of three groups: (i) HIT, n=19, 4 min at 100% AV, 4 min passive recovery, 4–6 bouts per session; (ii) SMIT, n=20, 30 s at 130% AV, 150 s passive recovery, 7–12 bouts per session; and (iii) control group, n=16, 30 min continuous running at 75% AV. Groups trained three times per week for six weeks. When time to complete each test were compared among groups: (i) improvements in 3000 m time trial performance were greater following SMIT than continuous running, and (ii) improvements in 40 m sprint and RSA performance were greater following SMIT than HIT and continuous running. In addition, a gender effect was observed for the 3000 m time trial only, where females changed more following the training intervention than males. In summary, for concurrent improvements in endurance, sprint and repeated sprint performance, SMIT provides the greatest benefits for physically active individuals.  相似文献   

13.
Abstract

The purpose of this investigation was to study the effect of swimming on selected components of athletic performance as measured by the following tests: back strength, leg strength, bicycle ergometer (combination of strength and endurance, but predominantly endurance), and vertical jump (explosive power). Subjects were pretested for three days on each test, after which they participated in 45 minutes of swimming, and performance was tested oh one test one hour after the swim on any given day. A single day's swimming was found to significantly affect the vertical jump, but other performance tests were not affected.  相似文献   

14.
Purpose:The present study aimed to examine the link between physical activity(PA)and life satisfaction in a large international study of adolescents.We also aimed to test whether overweight and underweight perceptions act as mediators and whether age and sex acted as moderators.Methods:For this purpose,we analyzed data from the Health Behavior in School-aged Children study,which comprises 727,865 observations from 44 nations at 4 measurement occasions.Results:Multilevel analyses revealed a positive link between PA and life satisfaction.In addition,underweight and overweight perceptions mediated the effect of PA on life satisfaction.We further found that age and sex acted as moderators.In older adolescents,stronger effects were found in the links between PA and life satisfaction,PA and overweight perception,and both weight perceptions and life satisfaction.In addition,in female adolescents,the link between overweight perception and life satisfaction was stronger.Conversely,the links between PA and both weight perceptions were stronger for boys.Conclusion:The results suggest that weight perception explains part of the relationship between PA and life satisfaction in adolescents and that these effects vary as a function of age and sex.  相似文献   

15.
Abstract

From the records in three track-and-field events (standing broad jump, softball throw, and six-second run), the ages, the heights, and the weights were obtained from 882 boys and 900 girls ranging in ages from 9 to 17 years. The relationship between ability in athletics (as measured by the records in the three track-and-field events) and the variables of age, height, and weight was, for the boys and for the girls, found to be nonlinear.  相似文献   

16.
Purpose: Decline of motor performance in older individuals affects their quality of life. Understanding the contribution of sport-related training in advanced ages might help to attenuate motor performance decay as one gets older. The purpose of our study was to evaluate the extent to which long-lasting training in running or sport-specific skills during old age preserves motor performance in different motor tasks. Method: Older runners and tennis players with at least 10 years of training were assessed as were age-matched and young exercisers. Performance was evaluated for 6 motor tasks requiring different functions of sensorimotor control expected to decline with aging. Results: Analysis revealed that runners had increased aerobic fitness in comparison with the other older participants and that they presented similar performance to older exercisers in the motor tasks. Tennis players outperformed the other groups of older participants on coincident timing and simple reaction time and achieved similar performance to the young group on the timing task. Conclusions: These results suggest selective maintenance of task-specific processing through extensive practice of tennis-related motor skills in older adults.  相似文献   

17.
Purpose: Suprapostural task performance (manual tracking) and postural control (sway and frequency) were examined as a function of attentional focus, age, and tracking difficulty. Given the performance benefits often found under external focus conditions, it was hypothesized that external focus instructions would promote superior tracking and reduced postural sway for both age groups, most notably as a function of tracking difficulty. Method: Postural sway, frequency of postural adjustments, and tracking accuracy under two levels of task difficulty were assessed for younger (M age = 20.98 years) and older (M age = 70.80 years) participants while they manually tracked a pursuit-rotor target. Participants received instructions to focus on either their actions (internal focus) or the effect of their actions (external focus). Results: Analyses revealed a beneficial effect of an external focus on suprapostural performance on the less-difficult (0.5 Hz) tracking task, and this performance was associated with a modest improvement in medial-lateral postural sway. Conclusion: The findings offer limited support for external focus-of-attention benefits under a mildly challenging tracking task. While older adults tend to adopt a conservative postural control strategy regardless of tracking task difficulty, external focus instructions on a suprapostural task promoted a modest, beneficial shift in postural control.  相似文献   

18.
Given that physical activity (PA) tends to decrease with age during adolescence, addressing factors that affect change is important. This study examined the similarity and interdependence of PA as influenced by psychosocial factors among adolescent best friend dyads. A total of 660 adolescents, representing 330 best friend dyads, completed questionnaires with regard to PA, sitting time, perceived exercise benefits and barriers, physical self-perception and social support for PA. Dyads were also identified as reciprocal and non-reciprocal best friends; reciprocal means that both considered each other best friends and non-reciprocal were those in which only one considered the other a best friend. Data were analysed using a hierarchical linear model framework. Results indicated significant similarities between reciprocal best friend dyads for PA and sitting time, and for sitting time in non-reciprocal best friends (P values <.01). Psychosocial variables were associated with PA in reciprocal best friend dyads and with sitting time in reciprocal and non-reciprocal best friend dyads. Best friend gender, regular sports practice of the person, perceived exercise barriers of the best friend and best friend social support were the best predictors for PA.  相似文献   

19.
Abstract

A number of physical measurements were taken on 107 boys aged 7 through 17 who were members of two AAU-age-group swim teams. A number of other variables were recorded including best competitive swimming times for each of the four competitive strokes. Each time was entered as the dependent variable in a stepwise multiple regression computer program, with all other variables being entered as possible predictors. Variables found significant in at least one analysis were length of time in competition, foot size, age within age group, biceps size, skinfold, height for age, center of gravity, ankle flexion, and waist size.  相似文献   

20.
Purpose: This study aimed to investigate the relationship between fundamental movement skills (FMS) and markers of health among a cohort of Irish primary school children. Methods: Participants (N = 296, mean age: 7.99 ± 2.02 years) were senior infant (n = 149, mean age: 6.02 ± 0.39 years) and 4th class (n = 147, mean age: 9.97 ± 0.40 years) students from three primary schools in Cork, Ireland. FMS proficiency (TGMD-2) and markers of health (BMI percentile, waist circumference percentile, blood pressure percentiles, resting heart rate, cardiorespiratory fitness, objectively measured physical activity; PA) measurements were recorded. Correlation and hierarchical stepwise multiple linear regression analyses were conducted to investigate the relationship between FMS and markers of health. Results: A small, positive relationship was found between FMS (Gross Motor Quotient; GMQ) and cardiorespiratory fitness with small negative correlations between GMQ and 550 m time SDS among 6-year-olds (r(129) = ?.286, p < .05) and 10-year-olds (r(132) = ?.340, p < .05). A moderate, positive correlation was found between GMQ and light PA (r(71) = .400, p < .05). Small positive correlations were revealed between GMQ and moderate PA (r(71) = .259, p < .05) and between GMQ and total PA (r(71) = .355, p < .05). After adjusting for age, sex, the interaction effect of age and sex, and school attended, FMS explained 15.9% and 24.8% of the variance in 550 m time SDS among 6- and 10-year-olds, respectively, and 6% and 6.5% of the variance in light PA and moderate PA, respectively. After adjusting for age and sex, FMS explained 11.6% of the variance in total PA. Conclusion: A wide range of FMS is important for children’s cardiorespiratory fitness and PA.  相似文献   

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