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The benefits associated with being physically active are well documented, but a significant proportion of the population is insufficiently active. Physical inactivity is a major health risk factor in our society, and physical education programs are consistently identified as a means to address this concern. The purpose of this article is to use the social-ecological model as a framework to examine ways in which physical education programs can play an important role in promoting physical activity. Policies that require time allocations and resources for physical education and physical activity in schools and community designs that provide infrastructure that makes being physically active accessible and convenient are important factors in making schools and communities healthier spaces. It is clear, however, that policies alone are not sufficient to address concerns about physical inactivity. We must consider individual factors that influence decisions to be physically active in efforts to engage children in physical education programs that promote active lifestyles. The learning climate that teachers create determines what students do and learn in physical education classes. Ensuring that students see value in the content presented and structuring classes so that students believe they can experience success when they exert effort are key elements in an effective motivational climate. Efforts to address public health concerns about physical inactivity require a comprehensive approach including quality physical education. It is critical that kinesiology professionals emerge as leaders in these efforts to place physical education programs at the center of promoting children's physical activity. 相似文献
2.
Stephen P. Messier Mary Elizabeth Dill 《Research quarterly for exercise and sport》2013,84(4):341-343
Abstract Influence from parents and friends on adolescents' self-reported level of leisure-time physical activity was examined through measures of (a) perceived leisure-time physical activity of parents and best friend, (b) perceived direct support for physical activity from parents and friends, (c) direct help from parents in exercising vigorously, and (d) perceived value of physical activity of parents and friends. The present analysis included 904 students in western Norway (M age 13.3 years, SD 0.3) who took part in a health behavior survey, which included questions regarding physical activity. Students completed a confidential questionnaire at school All four measures of influence were positively related to students' activity levels. None of the examined measures was clearly stronger than the other. Parental and peer physical activity level and parental and peer support for physical activity seem to influence the reported physical activity level of the respondents. The findings indicate that, by serving as models and supporters, significant others have an important impact in promoting physical activity in young adolescents. 相似文献
3.
Stephen P. Messier Mary Elizabeth Dill 《Research quarterly for exercise and sport》2013,84(4):345-351
Abstract The purpose of this study was to determine the effects of a Nautilus circuit weight training program on muscular strength and maximal oxygen uptake ([Vdot]O 2 max) by comparing these effects to those produced by adhering to either a free weight (FW) strength training program or a running (R) program. Male college students who voluntarily enrolled in either a FW training class (n = 11), a Nautilus (N) circuit weight training class (n= 12), or a R conditioning class (n= 13) were subjects for this investigation. All groups participated in their respective programs 3 days per week for 10 weeks. Strength was assessed using a Cybex II isokinetic dynamometer set at an angular velocity of 60° · s ?1 and a damping of 2. The FW group served as the control group for the assessment of [Vdot]O 2 max changes, while the R group served as controls for the assessment of strength differences. ANCOVA revealed that the N and R groups experienced significant (p < .01) increases in [Vdot]O 2 max expressed in L · min ?1 (10.9 and 11.4%), ml · kg ?1 · min ?1 (10.8 and 11.7%), and ml · kgLBW ?1 · min ?1 (7.1 and 7.5%) when compared to the FW group. There were no significant differences between the N and R groups. There were no significant differences among groups in final peak torque values (after covariance), and torque at the beginning and end of the range of motion for the knee extensors, knee flexors, elbow extensors, and elbow flexors. In general, isokinetic strength values elicited by the N group compared favorably to those generated by the FW group. It was concluded that for a training period of short duration, Nautilus circuit weight training appears to be an equally effective alternative to standard free weight (strength) and aerobic (endurance) training programs for untrained individuals. 相似文献
4.
Stephen P. Messier Warren D. Franke W. Jack Rejeski 《Research quarterly for exercise and sport》2013,84(4):273-279
Abstract The purpose of this study was to determine the effects of stride length variations on ratings of perceived exertion (RPEs) in experienced recreational runners. Twenty-eight male college students were randomly divided into equal-sized treatment and control groups. The treatment group performed five 15 min altered stride length runs, each separated by a minimum of 48 hr. The five trials involved running with a freely chosen stride length (FCSL) and a FCSL altered by +14%, +7%, ?14%, and ?7%. The control group was utilized to monitor changes in subjects' RPEs as a result of practice effects developed through repeated bouts of treadmill running. Results revealed that the treatment group's local and general RPEs for the over striding runs (+14%, +7%) were significantly greater (p < .01) than RPEs recorded during the FCSL run. Additionally, there was a marginally significant difference (p < .05) in local RPEs between the FCSL run and the extreme understriding run (?14%). Analysis of variance on the control group's RPE data suggests that neither local nor general RPEs changed significantly in repeated FCSL runs across the six-week testing period. The results of this study suggest that experienced recreational runners perceive differences in exertion accompanying changes in stride length. 相似文献
5.
The Mechanics of Batting: Analysis of Ground Reaction Forces and Selected Lower Extremity Kinematics
Abstract The purpose of this study was to examine variations in ground reaction forces and selected lower extremity kinematics during the stride and swing phases of batting. High speed photography (100 fps) employing direct linear transformation methodology and a force plate were used to record three-dimensional kinematic and kinetic data for 7 female fast pitch softball batters. Mean vertical forces (Fz) of the right or rear foot increased to approximately 1 BW during the stride. Once the left or forward foot made contact with the ground after completion of the stride, right Fz forces decreased to .43 BW while left Fz forces rapidly increased to 1.6 BW at contact. The mean decrease in right Fz forces from peak force until contact was 55%, and the ratio of left to right Fz forces; at impact was 3.67:1. Right mediolateral forces (Fx) were exerted laterally, away from the batter, and were responsible for initiating movement of the body toward the pitched ball. As the left foot made contact with the ground at completion of the stride, left Fx forces were exerted laterally toward the pitched ball. The reaction to these forces retarded the batter's forward momentum, increased stability, and caused the left hip and knee to extend as contact approached. Right and left anteroposterior forces (Fy) acted in opposite directions (right foot pushing backward, left foot pushing forward), and were responsible for rotating the hips and upper body in a counterclockwise direction toward the pitched ball. Horizontal angular deceleration of both thighs just prior to contact was due, in part, to a decrease in these forces. These data may prove helpful when attempting to identify atypical batting patterns, and when considering improvements in shoe design. In the latter instance, force production and stability may be enhanced by aligning the cleats along the lines of action of the applied resultant shear forces. 相似文献
6.
John R. Lyne 《Communication quarterly》2013,61(3):202-208
The performance of speech acts requires interpretive conditions that are best conceived within a semiotic frame. Three variables within these interpretive conditions are considered: (1) the options permitted or suggested by the structure of the discourse, (2) the degree to which illocutionary force is made explicit, and (3) the definition of the situation. Each of these suggests promising lines of confluence for the speech‐acts perspective and the rhetorical tradition, both of which focus on the pragmatic uses of codes. 相似文献
7.
Michael C. Lyne Nomonde Jonas Gerald F. Ortmann 《The Journal of Agricultural Education and Extension》2018,24(1):51-64
Purpose: This study evaluates the impact of an outsourced extension service delivered by Lima Rural Development Foundation (Lima) in the Umzimkhulu district of South Africa. The evaluation is conducted at both the household and program levels.
Design/methodology/approach: Household impacts were estimated using two-stage regression with instrumental variables to account for selection bias. Gains in household income were extrapolated to estimate the net incremental benefit of the program and its financial return at district level. These analyses were underpinned by a rigorous sampling design.
Findings: The results show that the outsourced extension service made a significant and substantial contribution to household crop income and net income. In addition, clients perceived a range of socio-economic benefits such as better diets, improved product quality, and job creation. Analysis of the financial cost and benefit of the extension service at district level suggests an annual net incremental benefit of R5 million (US$0.4 million), and a 95% probability that returns to the service exceeded 20% in 2012/2013.
Practical implications: These results suggest that there is good reason for donors to continue funding effective extension services to small farmers in areas of high agricultural potential.
Theoretical implications: This is an empirical study. It uses well-established methods to measure the impact but introduces a local economy multiplier to capture some of the indirect effects of agricultural extension.
Originality/value: This research is valuable as very few studies worldwide have evaluated the impact of agricultural extension services at both the farm and program levels. 相似文献
8.
Effects of a verbal and visual feedback system on running technique, perceived exertion and running economy in female novice runners 总被引：1，自引：0，他引：1
The purpose of this study was to determine the effects of a verbal and visual feedback system on running technique, ratings of perceived exertion (RPE), and running economy. Twenty-two female novice runners were randomly assigned to experimental (n = 11) and control (n = 11) groups. The experimental subjects received verbal and visual feedback concerning their running technique prior to and during each training run. Training involved 15 20-min treadmill running sessions over a 5-week period. The control group adhered to the same training routine but did not receive feedback concerning their running technique. High-speed (100 Hz) photography was used to collect biomechanical data. A submaximal oxygen consumption test and Borg's RPE scale were used to collect data concerning running economy and perceived exertion, respectively. Statistical analysis using ANCOVA revealed that the proposed feedback system had a significant (P less than 0.01) effect on the experimental group's running technique by affecting the following desired changes relative to the control group: greater relative stride lengths, shorter support time, greater ankle dorsiflexion during support and greater knee flexion during support and non-support. There were no significant differences between the groups in submaximal VO2 or RPE. The results of this study suggest that verbal and visual feedback are effective means of eliciting modifications in running style in female novice runners. The link between modifications in running style and improvements in running economy and perceived exertion remains unclear. 相似文献
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10.
Karelis AD Fontaine J Messier V Messier L Blanchard C Rabasa-Lhoret R Strychar I 《Journal of sports sciences》2008,26(9):935-940
The purpose of this study was to examine the psychosocial correlates of cardiorespiratory fitness (VO2peak) and muscle strength in overweight and obese sedentary post-menopausal women. The study population consisted of 137 non-diabetic, sedentary overweight and obese post-menopausal women (mean age 57.7 years, s = 4.8; body mass index 32.4 kg.m(-2), s = 4.6). At baseline we measured: (1) body composition using dual-energy X-ray absorptiometry; (2) visceral fat using computed tomography; (3) insulin sensitivity using the hyperinsulinaemic-euglycaemic clamp; (4) cardiorespiratory fitness; (5) muscle strength using the leg press exercise; and (6) psychosocial profile (quality of life, perceived stress, self-esteem, body-esteem, and perceived risk for developing chronic diseases) using validated questionnaires. Both VO2peak and muscle strength were significantly correlated with quality of life (r = 0.29, P < 0.01 and r = 0.30, P < 0.01, respectively), and quality of life subscales for: physical functioning (r = 0.28, P < 0.01 and r = 0.22, P < 0.05, respectively), pain (r = 0.18, P < 0.05 and r = 0.23, P < 0.05, respectively), role functioning (r = 0.20, P < 0.05 and r = 0.24, P < 0.05, respectively), and perceived risks (r = -0.24, P < 0.01 and r = -0.30, P < 0.01, respectively). In addition, VO2peak was significantly associated with positive health perceptions, greater body esteem, and less time watching television/video. Stepwise regression analysis showed that quality of life for health perceptions and for role functioning were independent predictors of VO2peak and muscle strength, respectively. In conclusion, higher VO2peak and muscle strength are associated with a favourable psychosocial profile, and the psychosocial correlates of VO2peak were different from those of muscle strength. Furthermore, psychosocial factors could be predictors of VO2peak and muscle strength in our cohort of overweight and obese sedentary post-menopausal women. 相似文献