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1.
ugar was highest in Sweet-guangyuan;the second,in Sweet-luzi and the lowest,in Sweet-shazi.The content of vitamin C in Sweet-shazi was the highest,while Sweet-luzi was the lowest.The content of vitamin C and total sugar incre  相似文献   

2.
Open-boat sailing boomed in Sydney, Australia, during the 1890s, as a number of new sailing clubs emerged in the city's working waterfront suburbs. Open boats have since been remembered as ‘typically Australian’, radically opposed to the forms and ceremonies of the yachting establishment, and even as sharing the characteristics of the bushman, an archetype of Australian national identity. This article traces the rise of open-boat sailing as a working-class spectator sport and the associated image of an ‘open boat legend’. It argues that open-boat sailing remained a Sydney legend in the 1890s. However, links to working traditions and place have made it possible for popular histories of sailing and yachting to present the open boats and sailors of the period with identifiably Australian characteristics.  相似文献   

3.
Participation trends in 100 m (161 km) ultramarathon running competitions in North America were examined from race results from 1977 through 2008. A total of 32, 352 finishes accounted for by 9815 unique individuals were identified. The annual number of races and number of finishes increased exponentially over the study period. This growth in number of finishes occurred through a combination of (1) an increase in participation among runners ≥40 years of age from less than 40% of the finishes prior to the mid-1980s to 65–70% of the finishes since 1996, (2) a growth (p < 0.0001) in participation among women from virtually none in the late 1970s to nearly 20% since 2004, and (3) an increase in the average annual number of races completed by each individual to 1.3. While there has been considerable growth in participation, the 161 km ultramarathon continues to attract a relatively small number of participants compared with running races of shorter distances.  相似文献   

4.
The present study explored the method of testing muscle mechanical properties through the linear force–velocity (F–V) relationships obtained from loaded vertical jumps. Specifically, we hypothesised that the F–V relationship parameters depicting the force, power, and velocity of the tested muscles will differ among individuals of different physical fitness. Strength trained, physically active, and sedentary male participants (N = 10 + 10 + 10; age 20–29 years) were tested on maximum countermovement and squat jumps where manipulation of external loads provided a range of F and V data. The observed F–V relationships of the tested leg muscles were approximately linear and mainly strong (median correlation coefficients ranged from 0.77 to 0.92; all p < 0.05), independently of either the tested group or the jump type. The maximum power revealed higher values in the strength trained than in the physically active and sedentary participants. This difference originated from the differences in F-intercepts, rather than from the V-intercepts. We conclude that the observed parameters could be sensitive enough to detect the differences among both the individuals of different physical fitness and various jump types. The present findings support using loaded vertical jumps and, possibly, other maximum performance multi-joint movements for the assessment of mechanical properties of active muscles.  相似文献   

5.
Cardiovascular disease is the leading cause of human death worldwide. Autophagy is an evolutionarily conserved degradation pathway,which is a highly conserved cellular degradation process in which lysosomes decompose their own organelles and recycle the resulting macromolecules.Autophagy is critical in maintaining cardiovascular homeostasis and function, and excessive or insufficient autophagy or autophagic flux can lead to cardiovascular disease. Enormous evidence indicates that exercise training plays a beneficial role in the prevention and treatment of cardiovascular diseases. The regulation of autophagy during exercise is a bidirectional process. For cardiovascular disease caused by either insufficient or excessive autophagy, exercise training restores normal autophagy function and delays the progression of cardiovascular disease.An in-depth exploration and discussion of exercise-mediated regulation of autophagy in the cardiovascular system can broaden our view about the prevention of various autophagy-related diseases through exercise training. In this article, we review autophagy and its related signaling pathways,as well as autophagy-dependent beneficial effects of exercise in cardiovascular system.  相似文献   

6.
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7.
Abstract

In this study, we evaluated agreement among three generations of ActiGraph? accelerometers in children and adolescents. Twenty-nine participants (mean age = 14.2 ± 3.0 years) completed two laboratory-based activity sessions, each lasting 60 min. During each session, participants concurrently wore three different models of the ActiGraph? accelerometers (GT1M, GT3X, GT3X+). Agreement among the three models for vertical axis counts, vector magnitude counts, and time spent in moderate-to-vigorous physical exercise (MVPA) was evaluated by calculating intraclass correlation coefficients and Bland-Altman plots. The intraclass correlation coefficient for total vertical axis counts, total vector magnitude counts, and estimated MVPA was 0.994 (95% CI = 0.989–0.996), 0.981 (95% CI = 0.969–0.989), and 0.996 (95% CI = 0.989–0.998), respectively. Inter-monitor differences for total vertical axis and vector magnitude counts ranged from 0.3% to 1.5%, while inter-monitor differences for estimated MVPA were equal to or close to zero. On the basis of these findings, we conclude that there is strong agreement between the GT1M, GT3X, and GT3X+ activity monitors, thus making it acceptable for researchers and practitioners to use different ActiGraph? models within a given study.  相似文献   

8.
采用问卷调查法、文献资料法、访谈法等研究方法,对在高校女生体育课中引入舞蹈课程的可行性进行较全面的分析。结果显示：舞蹈以其独特的特性和可见的练习效果深受广大学生,尤其是女大学生的喜爱与欢迎,因此,高校针对女大学生开设舞蹈课是符合现代高校体育教学发展的需求,是很有必要的。  相似文献   

9.
This study aims to examine the changes in the role of government in Chinese elite sport development during three stages between 1949 and 2012. By analyzing the literature in terms of value orientation, governance scope and resource allocation methods, the study shows that the government functioned differently in each of the three stages. The changes to the government's involvement in Chinese elite sport development occurred in tandem with economic and social development in China.  相似文献   

10.
Abstract In this study, we evaluated agreement among three generations of ActiGraph? accelerometers in children and adolescents. Twenty-nine participants (mean age?=?14.2?±?3.0 years) completed two laboratory-based activity sessions, each lasting 60?min. During each session, participants concurrently wore three different models of the ActiGraph? accelerometers (GT1M, GT3X, GT3X+). Agreement among the three models for vertical axis counts, vector magnitude counts, and time spent in moderate-to-vigorous physical exercise (MVPA) was evaluated by calculating intraclass correlation coefficients and Bland-Altman plots. The intraclass correlation coefficient for total vertical axis counts, total vector magnitude counts, and estimated MVPA was 0.994 (95% CI?=?0.989-0.996), 0.981 (95% CI?=?0.969-0.989), and 0.996 (95% CI?=?0.989-0.998), respectively. Inter-monitor differences for total vertical axis and vector magnitude counts ranged from 0.3% to 1.5%, while inter-monitor differences for estimated MVPA were equal to or close to zero. On the basis of these findings, we conclude that there is strong agreement between the GT1M, GT3X, and GT3X+ activity monitors, thus making it acceptable for researchers and practitioners to use different ActiGraph? models within a given study.  相似文献   

11.
Abstract

The purpose of this study was to establish percentile norms and to compare skinfold and other anthropometric measurements of 647 Italian, Jewish, and Negro preadolescent boys from the Boston, Massachusetts area. Skinfolds were measured at five sites. Other measurements included height, weight, bi-iliac diameter, and selected girths.

Correlations were determined between skinfolds and selected body build components. Interskinfold r's ranged from moderate to high values. The largest percentile scores were found within the Jewish group. Analysis of variance was employed to compare the body fat, height, and weight of each group. Significant differences were found relative to certain skinfolds and weight between ethnic groups at the 1 percent level.  相似文献   

12.
We examined psychometric properties of a Modified Physical Activity Questionnaire for Children (MPAQ-C). Thirty-two parents (Study 1), 40 students (6–9 years) and one of each student’s parents (Study 2), and 625 parents (Study 3) completed the MPAQ-C. The MPAQ-C (six items) measured children’s physical activity (PA) after school, and during evenings and weekends for 7 days. Test–retest reliability (Study 1) and convergent validity (Study 2) were measured. Factor validity of the MPAQ-C (Study 3) was examined using confirmatory factor analysis. A single-factor model of the MPAQ-C fit the data well (χ2 (9) = 42.78, p < .001; comparative fit index[CFI] = .977; non-normed fit index [NNFI] = .962; root mean square error of approximation [RMSEA] = .079 [90% confidence interval {CI} = .057 to .11]), with good test–retest reliability, composite reliability (.80) and convergent validity. The factor loadings of MPAQ-C were invariant across fathers/mothers (Δχ2 (6) = 3.44, p > .05). The MPAQ-C is a suitable parent proxy for measuring young Chinese children’s PA.  相似文献   

13.
Background: Many studies have found that Physical Education and Health (PEH) is a popular subject among the majority of pupils. Still, there is an on-going discussion concerning the aim of PEH and what legitimises it as a school subject. It is difficult to identify what knowledge appears as legitimate within PEH, and this creates conflicts within the field.

Purpose: The main purpose of this study is to contribute to the on-going debate regarding the knowledge content and the identity problems described in PEH. The conceptual framework used is curriculum theory, inspired by Bernstein's and Lundgren's theoretical work on the social construction of knowledge and the relationship between the production and reproduction of curricular knowledge, further developed by Linde. The specific research questions are the following: (1) What knowledge appears as legitimate in the subject in Sweden on these three levels: In the syllabus, as viewed by teachers, and during the realisation of lessons? (2) What are the similarities and differences between these levels with regard to legitimate subject knowledge? (3) Can we understand the described identity problem in the subject with the help of what knowledge appears legitimate?

Research design and data collection: The data used originate from three empirical materials obtained in Sweden from 2003 to 2005: the syllabus valid for compulsory school (i.e. Lpo 94) at the time the interviews and observations took place, material from semi-structured interviews with six PEH teachers who teach year 9 in four different secondary schools, and information from 20 videotaped PEH lessons taught by the interviewed teachers.

Findings: The results indicate that one can distinguish two largely dissimilar objects of learning which differ most markedly between the field of formulation and the field of transformation and realisation. The content knowledge of the field of formulation is largely reformulated in the field of transformation, but no major change takes place from the field of transformation to the field of realisation. The ‘formulated object of learning’ primarily comprises functional physical exercise, conceptual development, and the understanding of health and lifestyles. The ‘realised object of learning’ consists of formalised sport and physical exercise, with a minor focus on conceptual development.

Conclusions: Since two largely different objects of learning emerge in the subject, consensus is low regarding what knowledge is considered legitimate; the knowledge domain on the primary field most likely differs between the two arenas. A main problem for PEH in trying to gain legitimacy is that there are many different actors in the primary field who are related to and have interest in the subject and the knowledge basis of the subject derives from several different academic disciplines and from non-academic ones.  相似文献   

14.
Background:Exercise is considered as an important intervention for treatment and prevention of several diseases,such as osteoarthritis,obesity,hypertension,and Alzheimer's disease.This review summarizes decadal exercise intervention studies with various rat models across 6 major systems to provide a better understanding of the mechanisms behind the effects that exercise brought.Methods:PubMed was utilized as the data source.To collect research articles,we used the following terms to create the search:(exercise[Title]OR physical activity[Title]OR training[Title])AND(rats[Title/Abstract]OR rat[Title/Abstract]OR rattus[Title/Abstract]).To best cover targeted studies,publication dates were limited to"within 11 years."The exercise intervention methods used for different diseases were sorted according to the mode,frequency,and intensity of exercise.Results:The collected articles were categorized into studies related to 6 systems or disease types:motor system(17 articles),metabolic system(110 articles),cardiocerebral vascular system(171 articles),nervous system(71 articles),urinary system(2 articles),and cancer(21 articles).Our review found that,for different diseases,exercise intervention mostly had a positive effect.However,the most powerful effect was achieved by using a specific mode of exercise that addressed the characteristics of the disease.Conclusion:As a model animal,rats not only provide a convenient resource for studying human diseases but also provide the possibility for exploring the molecular mechanisms of exercise intervention on diseases.This review also aims to provide exercise intervention frameworks and optimal exercise dose recommendations for further human exercise intervention research.  相似文献   

15.
In this review, we critically evaluate the scientific research into the morphology and physiology of cricket batsmen. We consider all aspects of the motor control of this skill, in the context of research into dynamic interceptive actions, the biomechanics (kinematics and kinetics) of the various phases of batting strokes and injuries to batsmen. Some attention is also devoted to batting equipment and to psychological factors in batting. Because of the lack of published scientific research into women's cricket, this review focuses on the men's game and covers research on batsmen of various playing standards. For the future, we see as a high priority research into injury mechanisms, rather than simple injury statistics, and the role of cricket equipment design in injury prevention. A second priority is for multi- or inter-disciplinary research, linking the biomechanics of batting to the underlying motor control of the movements and the effect of environmental information. Biomechanical studies of the variability of the batsman's movements are needed, and these should be related to the compensatory variability proposal of ecological psychology. Clearly, there is also a need for scientific research into batting in women's cricket, which has been inadequately researched to date.  相似文献   

16.
ABSTRACT

The extent to which travel has affected Super Rugby teams’ performances was analysed using outcomes of all matches played from the beginning of the competition in 1996 to the end of the 2016 season. Points difference and matches won or lost were predicted with general and generalized mixed linear models. The predictors were the linear effects of number of time zones crossed and travel duration based on the teams’ locations for each match and their locations in the previous week. The away-match disadvantage was also estimated, along with trends in all these effects. In 1996 the predicted combined effect of eastward travel across 12 time zones was a reduction of 5.8 points scored per match, resulting in 4.1 more matches lost every 10 matches. Corresponding effects for westward travel were 6.4 points and 3.1 matches. In 2016 effects travelling eastward were 3.7 points and 2.3 matches, whereas travelling westward the effects were 3.7 points and 1.5 matches. These travel effects were due mainly to the away-match disadvantage: 5.7 points and 3.2 matches in 1996; 5.2 points and 2.3 matches in 2016. Teams in Super Rugby are dealing successfully with long-haul travel and should now focus on reducing the away-match disadvantage.  相似文献   

17.
BackgroundThere are limited data on factors that predict an increased risk of multiple injuries among distance runners. The objective of this study was to determine risk factors that are predictive of individual runners with a high annual multiple injury risk (MIR).MethodsA retrospective, cross-sectional study at 4 annual (2012–2015) Two Oceans 21.1 km and 56.0 km races in South Africa with 75,401 consenting race entrants. Running-related injury data were collected retrospectively through an online pre-race medical screening questionnaire. The average number of injuries for each runner every year was calculated by taking a runner's race entry history and injury history into account and categorizing entrants into 4 MIR categories (high, intermediate, low, and very low (reference)). Multiple logistic regression modeling (odds ratios) was used to determine whether the following factors were predictive of a high MIR (average > 1 injury/year): demographics, training and racing, chronic-disease history (composite chronic disease score (CCDS)), and history of allergies.ResultsOf all entrants, 9.2% reported at least 1 injury, and 0.4% of entrants were in the high MIR category; the incidence rate was 2.5 injuries per 10 runner-years (95% confidence interval (95%CI): 2.4–2.7). Significant factors predictive of runners in the high MIR category were: running for > 20 years: OR = 2.0 (95%CI: 1.3–3.1; p = 0.0010); a higher CCDS: OR = 2.2 (95%CI: 2.0–2.4; p < 0.0001); and a history of allergies: OR = 2.8 (95%CI: 2.0–3.8; p < 0.0001).ConclusionRunners who have been running recreationally for > 20 years and those with multiple chronic diseases or a history of allergies were at higher risk of multiple running-related injuries. This high-risk group can be targeted for further study and possible injury-prevention interventions.  相似文献   

18.
《Sport Management Review》2016,19(4):431-440
The “Linsanity” phenomenon attracted an increase in attention toward the National Basketball Association (NBA) for a short period of time. Drawing on self-categorization theory to elucidate current literature on team identification, this research proposed a conceptual model delineating the social psychological process for international consumers during the phenomenon. Using an online survey with a convenience sample in Taiwan, structural equation modeling, including confirmatory factor analysis (CFA) and path analysis, validated the conceptual model and confirmed the relationships between constructs in the model. Results indicated that Taiwanese identification positively influenced player identification, while player identification mediated the relationship between Taiwanese identification and team identification. Consequently, team identification positively influenced NBA involvement. The research findings together contribute to explicating the mechanism behind consumers’ self-categorization process during the “Linsanity” phenomenon while offering implications for international sport marketing. The research concludes with suggestions for future research.  相似文献   

19.
The article presents the most important results of metabolic (hormonal) study of dosed vibration training (DVT).The author presents vibrating training as an alternative to anabolic steroids on the basis of a comparison of the effectiveness of two types of stimulants - forbidden (doping) and non-medicinal non-invasive, relating to permitted physical means.The study shows that the level of androgens (testosterone),corticosteroids (cortisol), thyroid hormones (thyroxine,triiodothyronine),hormones of adenohypophysis (prolactin) increased under the effect of dosed vibration training.At the same time the level of hormones have no changes under traditional strength training with the use of a synthetic anabolic steroid (retabolil).For the duration of a limited period of time (1 microcycles) dosed vibrotraining causes a more powerful secretion of testosterone than the traditional strength training with the use of anabolic steroids. In this case,the overall time spent on the performance of the DVT training program comprises not more than 15% of the time spent on the traditional training exercises.  相似文献   

20.
The aim of the present study was to examine the effects of viscoelastic properties of human tendon structures during stretch?–?shortening cycle exercise. The elongation of tendon and aponeurosis of the medial gastrocnemius muscle of 26 participants was measured by ultrasonography while they performed ramp isometric plantar flexion up to the voluntary maximum, followed by a ramp relaxation. The relationship between estimated muscle force and tendon elongation during the ascending phase was fitted to a linear regression, the slope of which was defined as stiffness. The percentage of the area within the muscle force?–?tendon elongation loop relative to the area beneath the curve during the ascending phase was defined as hysteresis. In addition, maximal voluntary concentric contractions at 2.09 and 3.14 rad?·?s?1 with and without prior eccentric contractions were performed. The difference in the concentric torque at equivalent joint angles with and without prior eccentric contractions (i.e. pre-stretch augmentation) was negatively correlated with stiffness (P <?0.05) and hysteresis (P <?0.05). Furthermore, there was a higher correlation between the pre-stretch augmentation and the viscoelastic properties index – that is, the sum of normalized score values of stiffness and hysteresis (P <?0.01) – than with either stiffness or hysteresis alone. The results of this study suggest that performance during stretch?–?shortening cycle exercise is significantly affected by the viscoelastic properties of the tendon structures.  相似文献   

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