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21.
22.
研究假设是研究课题确定后依据一定的知识、事实和资料,对所研究问题的规律或原因做出的推测性论断和假定性说明,是研究之前预先设想的、暂时的理论,是对研究课题设想出的一种或几种可能的结论或答案。假设一般包括两个事件或概念之间的关系,用“如果……那么……”的句子来陈述。例如:如果教师对一名学生的评价越来越差,那么该生的自我评价也会变得越来越差。研究假设是我们在实施课题研究设计之前,必须明确的问题。在教育科学研究中,提出具体的研究假设具有非常重要的作用。一、为课题研究指明方向研究假设使研究目的更明确,研究范围更确…  相似文献   
23.
假日旅游经济是我国旅游经济发展中的一个新的增长点。本文对假日旅游经济的涵义、基本特征及产生的背景进行了论述,并提出了科学调控假日旅游经济的若干对策措施,以期有益于促使我国假日旅游经济持续、健康发展。  相似文献   
24.
Background: In Self-Determination Theory (SDT), a well-validated macro-theory on human motivation, a distinction is made between internally controlling teaching practices (e.g. guilt-induction and shaming) and externally controlling practices (e.g. threats and punishments, commands). While both practices are said to undermine students’ motivation, they would do so through somewhat differential motivational processes. Unfortunately, the relevance of the conceptual distinction between internally and externally controlling strategies has not been examined systematically. In the context of sport and physical education (PE), most studies on controlling teaching have either measured controlling teaching in an undifferentiated way or have focused on one particular feature of controlling teaching.

Purpose: The purpose of this study was to provide a more fine-grained picture on the differential de-motivational effects of internally and externally controlling teaching strategies in the domain of PE.

Participants: A total of 925 students with an average age of 15.80 years (±1.99) coming out of 92 classes taught by 22 different PE teachers participated in the present study.

Data analysis: Data on perceived controlling teaching style and students’ motivation were analyzed within a multilevel framework from both a variable-centered (regression analyses) and person-centered approach (cluster analyses).

Results: We found evidence for a distinction between perceived internally and externally controlling teaching. Both teaching styles were strongly related to each other (r?=?.54). At the level of zero-order correlations, both internally and externally controlling teaching related negatively to students’ intrinsic motivation and identified regulation and related positively to introjected regulation, external regulation, and amotivation. However, when both teaching styles were included simultaneously as predictors of motivation in the regression analyses, only internally controlling teaching predicted poor quality and low quantity of motivation. A cluster analysis revealed different profiles of perceived controlling teaching style, with two profiles being characterized by either high or low levels of the two types of controlling teaching and other profiles displaying elevated or reduced levels of one of the types of controlling teaching. This person-centered analysis confirmed that particularly students who perceive their PE teacher as internally controlling are likely to report poor-quality motivation.

Conclusion: Controlling teaching (and internally controlling teaching in particular) is related to maladaptive motivational outcomes. As such, it can be advised to PE-practitioners to refrain from using controlling strategies when teaching students. More research is needed to identify the conditions under which teachers’ behavior is perceived as externally and/or internally controlling.  相似文献   
25.
This study aimed to verify the prevalence and characteristics of sports injuries (SI) and determine the association between the physical activity level (PA) and SI with perception of health-related quality of life (HRQoL) in Brazilian basketball master athletes. A cross-sectional study was conducted with 410 male master athletes, between 35 and 85 years of age (mean 52.26, SD ±11.83). The HRQoL was assessed using the Medical Outcomes Study – Short Form-36. The PA was evaluated using the International Physical Activity Questionnaire. Information regarding SI was collected using the Reported Morbidity Survey. Poisson regression, as estimated by the prevalence ratio (PR), was used as a measure of the association of PA and SI with HRQoL. The majority of athletes showed a high SI prevalence (58.3%) and reported one injury (67.8%) that occurred during training (61.1%) and primarily affected a lower limb (74.6%). The adjusted regression models showed a positive association of PA with the Functional Capacity (PR = 1.46, 95% confidence interval [CI] = 1.12–1.90) and Physical Component (PR = 1.32, 95% CI = 1.03–1.70) of HRQoL. Furthermore, the SI were negatively associated with HRQoL in Functional Capacity (PR = 1.85, 95% CI = 1.51–2.27), Physical Aspects (PR = 3.99, 95% CI = 3.08–5.18), Pain (PR = 1.65, 95% CI = 1.26–2.16), Social Functioning (PR = 1.79, 95% CI = 1.41–2.27), Emotional Aspects (PR = 4.40, 95% CI = 3.35–5.78), Mental Health domains (PR = 1.37, 95% CI = 1.06–1.68), Physical Component (PR = 2.35, 95% CI = 1.90–2.90) and Mental Component (PR = 2.65, 95% CI = 2.14–3.29). These results highlighted that master athletes showed a high SI prevalence, primarily in the lower limbs. PA positively correlates with the physical HRQoL domain, whereas SI may decrease the HRQoL levels of both physical and mental domains.  相似文献   
26.
The purpose of this study was to investigate the effects of interval aerobic training combined with strength exercise in the same training session on body composition, and glycaemic and lipid profile in obese rats. Sixteen lean Zucker rats and sixteen obese Zucker rats were randomly divided into exercise and sedentary subgroups (4 groups, n = 8). Exercise consisted of interval aerobic training combined with strength exercise in the same training session. The animals trained 60 min/day, 5 days/week for 8 weeks. Body composition, lipid and glycaemic profiles and inflammatory markers were assessed.

Results showed that fat mass was reduced in both lean and obese rats following the exercise training (effect size (95% confidence interval (CI)) = 1.8 (0.5–3.0)). Plasma low-density lipoprotein–cholesterol and fasting glucose were lower in the exercise compared to the sedentary groups (= 2.0 (0.7–3.2) and 1.8 (0.5–3.0), respectively). Plasma insulin was reduced in exercise compared to sedentary groups (= 2.1 (0.8–3.4)). Some exercise × phenotype interactions showed that the highest decreases in insulin, homeostatic model assessment-insulin resistance, fasting and postprandial glucose were observed in the obese + exercise group (all, P < 0.01). The findings of this study suggest that interval aerobic training combined with strength exercise would improve body composition, and lipid and glycaemic profiles, especially in obese rats.  相似文献   

27.
Testing is one of the important tasks in any multi-step sport programme. In most ball games, coaches assess motor, physical and technical skills on a regular basis in early stages of talent identification in order to further athletes’ development. The purpose of the study was to investigate anthropometric variables and vertical jump heights as a free throw effectiveness predictor in water-polo players of different age groups. Two hundred and thirty-six young (10–18 years) male water-polo players partitioned into three age groups underwent anthropometric variables’ measures and squat- and countermovement-jump tests, and performed water-polo free throws. Anthropometric variables, vertical jump heights and throw speed – as a proxy for free throw effectiveness – resulted different over age groups. Particularly, throw speed changed from 9.28 to 13.70 m · s?1 (+48%) from younger to older players. A multiple-regression model indicated that body height, squat-jump height and throw time together explain 52% of variance of throw speed. In conclusion, tall height, high lower limb power and throwing quickness appeared to be relevant determinants for effective free throws. Such indications can help coaches during talent identification and development processes, even by means of novel training strategies. Further research is needed over different maturity statuses.  相似文献   
28.
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   
29.
ABSTRACT

The objective of this 1-year, longitudinal study was to examine the development of perceived competence, tactical skills, motivation, technical skills, and speed and agility characteristics of young Finnish soccer players. We also examined associations between latent growth models of perceived competence and other recorded variables. Participants were 288 competitive male soccer players ranging from 12 to 14 years (12.7 ± 0.6) from 16 soccer clubs. Players completed the self-assessments of perceived competence, tactical skills, and motivation, and participated in technical, and speed and agility tests. Results of this study showed that players’ levels of perceived competence, tactical skills, motivation, technical skills, and speed and agility characteristics remained relatively high and stable across the period of 1 year. Positive relationships were found between these levels and changes in perceived competence and motivation, and levels of perceived competence and speed and agility characteristics. Together these results illustrate the multi-dimensional nature of talent development processes in soccer. Moreover, it seems crucial in coaching to support the development of perceived competence and motivation in young soccer players and that it might be even more important in later maturing players.  相似文献   
30.
The objective of this study was to determine which chemical treatment used for disinfecting water in indoor swimming pools had the least impact on users' perceptions of health problems, and which generated the greatest satisfaction with the quality of the water. A survey on satisfaction and perceived health problems was given to 1001 users at 20 indoor swimming pools which used different water treatment methods [chlorine, bromine, ozone, ultraviolet lamps (UV) and salt electrolysis]. The findings suggest that there is a greater probability of perceived health problems, such as eye and skin irritation, respiratory problems and skin dryness, in swimming pools treated with chlorine than in swimming pools using other chemical treatment methods. Pools treated with bromine have similar, although slightly better, results. Other factors, such as age, gender, time of day of use (morning and afternoon) and type of user (competitive and recreational), can also affect the probability of suffering health problems. For all of the above, using combined treatment methods as ozone and UV, or salt electrolysis produces a lower probability of perceived health problems and greater satisfaction.  相似文献   
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