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931.
The purpose of this study was to test the validity of the games for understanding model by comparing it to a technique approach to instruction and a control group. The technique method focused primarily on skill instruction where the skill taught initially was incorporated into a game at the end of each lesson. The games for understanding approach emphasized developing tactical awareness and decision making in small game situations. Two physical education specialists taught field hockey using these approaches for 15 lessons (45 min each). The control group did not receive any field hockey instruction. Data were collected from 71 middle school children. Pretests and posttests were administered for hockey knowledge, skill, and game performance. Separate analyses of variance or analyses of covariance were conducted to examine group differences for cognitive and skill outcomes. The games for understanding group scored significantly higher on passing decision making than the technique and control groups during posttest game play and significantly higher than the control group for declarative and procedural knowledge. The games for understanding group scored significantly higher on control and passing execution than the other groups during posttest game play. For hockey skill, there were no significant differences among the treatment groups for accuracy, but the technique group recorded faster times than the control group on the posttest.  相似文献   
932.
Five women and 5 men were studied to examine the effects of submaximal exercise on thermoregulatory and hemodynamic variables during recovery in two environments: (a) control (C), 22 degrees C, 33% rh; and (b) hot humid (H), 32 degrees C. The participants exercised on a cycle ergometer at 60% of peak oxygen consumption for 35 min prior to 90 min of seated recovery. Sessions were identical, except for environment. Variables evaluated (p < .05) were: core temperature (TR), mean skin temperature (Ts), sweat rate (SR), heart rate (HR), stroke index (SI), cardiac index (CI), forearm blood flow (FBF), systolic blood pressure (SBP), and diastolic blood pressure (DBP). Men and women exhibited similar patterns of TR, Ts, and SR in both environments. Ts and SR (collapsed means for gender) were higher in the H than in the C. DBP was higher in men than in women throughout recovery in both environments. With combined means for gender, HR was higher in the H than in the C. CI, SI, FBF, and SBP were similar in both environments and returned to baseline within 15 min into recovery. These data suggest that heat dissipation during extended recovery was accomplished with similar contributions of cutaneous vasodilation and sweating in M and F. Furthermore, the moderate exercise level did not influence hemodynamics beyond 15 min of recovery in either environment.  相似文献   
933.
Purpose: Authorities recommend that schools provide a variety of opportunities for students to obtain physical activity (PA) before, during, and after school. This study assessed the prevalence of several school PA practices—including measures of quantity and quality of physical education (PE)—in elementary schools and examined the associations of PA practices with school resources (PE staffing, training, and facilities). Method: Surveys were obtained from respondents in nationally representative samples of elementary schools from 2009–2010 to 2011–2012 (1,831 schools). Results: Few schools (20.8%) provided students with PE class every day, but most (76.3%) had an appropriate PE student-to-teacher ratio ( ≤ 25:1). Many schools (74.0%) offered 20 min of recess daily, but fewer than half offered organized opportunities for PA before or after school (e.g., sports). After controlling for demographics and school size, having a full-time PE teacher and requiring PE teachers to obtain PE-related continuing education (CE) were associated with PE practices such as offering ≥ 150 min of PE per week (for 3rd-grade students) and testing PE knowledge, skills, and fitness. Required CE was also associated with a higher likelihood of offering PA during the school day (i.e., activity breaks and PA outside of PE class) and before or after the school day (i.e., afterschool PA programs). Conclusion: Few schools offer a broad array of PA programming. However, PE staffing and CE are positively associated with many PA practices including those outside of PE, possibly indicating that PE staff serve a crucial role in promoting a whole-school PA-supportive environment.  相似文献   
934.
This study examined the effect of health worry (i.e., cognitive aspect of anxiety resulting from concern for health) on walking difficulty in a nationally representative sample (N = 7,527) of older adults (M age = 76.83 years). The study further tested whether physical activity mediates the effect of health worry on walking difficulty in a 6-year follow-up design. Results of a mediation analysis using structural equation modeling showed that people with a high degree of health worry engaged in less physical activity (β = -.24, p < .001), and people who participated in less physical activity were more likely to report walking difficulty at the 6-year follow-up (β = -.22, p < .001). There was a significant indirect effect from health worry to walking difficulty through physical activity (β = .05, p < .001), controlling for demographic, psychosocial, and health related factors. Results suggested that inducing threat and worry may not be effective for physical activity promotion in the older population. More promising coping and regulation strategies are discussed.  相似文献   
935.
The purpose of this study was to determine if a difference in interleukin-6 (IL-6) and delayed onset muscles soreness (DOMS) exists in two different phases of the menstrual cycle. Nine runners performed one 75-min high-intensity interval running session during the early follicular (EF) phase and once during the midluteal (ML) phase of the menstrual cycle. Estrogen and progesterone levels were significantly reduced in the EF phase when compared to the ML phase. IL-6 levels increased from pre- to postexercise in the EF and ML phases (p < .001). There was no relationship between the IL-6 level and DOMS. The results suggest that menstruating female runners need not vary training throughout the month to reduce DOMS.  相似文献   
936.
937.
To adhere to the principle of “exercise specificity” exercise testing should be completed using the same physical activity that is performed during exercise training. The present study was designed to assess whether aerobic step exercisers have a greater maximal oxygen consumption (max VO2) when tested using an activity specific, maximal step exercise test (SET; arms and legs) versus a maximal running test (legs only). Female aerobic step exercisers (N=18; 20.7 ± 1.5 years) performed three maximal graded exercise tests (GXTs): 2 SETs; 1 treadmill test (TMT). The SET consisted of six 3-min progressive stages of alternate lead, basic step, basic step with biceps curls, knee raise with pull-down, repeater knee with pull-down, lateral lunge with pull-down, and side squat with shoulder presses. Stepping rate was 32 steps· min?1 on an 8-in (20.32 cm) step for stages 1–3, and a 10-in (25.4 cm) step for stages 4–6. Submaximal and maximal heart rate (HR) and oxygen consumption (VO2) were recorded at the end of each stage. Test–retest reliability for the first five stages of the SET ranged from .91 to .97 for HR, and from .84 to .96 for VO2. Maximal HR was significantly greater (p =.0001) for the SET (200 ± 6.2 beats·min?1) as compared to the TMT (193 ± 7.9 beats·min?1). No significant difference was found for max VO2 (42.9 ± 8.5, 41.2 ± 5.9 ml·kg?1·min?1, p =.14). The SET was a valid and reliable protocol for assessing responses of these aerobic step exercisers; however, max VO2 from a TMT did not differ significantly from the SET. Conversely, max HR obtained from the criterion TMT was 7 beats·min?1 lower than from the SET. If a training HR for step exercise (arms and legs exercise) is prescribed based on the max HR from treadmill exercise (legs only), then the training HR should be calculated from a TMT max HR that has been increased by 7 beats·min?1 to obtain an intensity of step exercise comparable to that of running.  相似文献   
938.
Bourdieu's analytic concept of habitus has provided a valuable means of theorising coach development but is yet to be operationalised in empirical research. This article redresses this oversight by drawing on a larger study that inquired into how the ‘coaching habitus’ of elite-level Australian and New Zealand rugby coaches structured their interpretation and use of the Game Sense approach to coaching to illustrate how habitus can be operationalised. It focuses on the identification of characteristics of the individual coaching habitus of four elite-level Australian rugby coaches and how they shape their interpretation and use of Game Sense. Drawing on suggestions made by Lau, we identify the characteristics of four individual ‘coaching habitus’ by examining their views on: (1) the characteristics of good coaches; (2) characteristics of great rugby players and how to develop them; and (3) their dispositions towards innovation in coaching.  相似文献   
939.
In this study, we examined the relationship between anthropometric, strength and power characteristics of rugby forwards, their body position when scrummaging, and their ability to apply force when scrummaging. Force applied to an instrumented scrum machine was measured for 56 players, both individually and as scrum packs. Measurements of body position for individuals were made by digitizing videotape records of the trials. Forty players subsequently had their anthropometry assessed and completed several strength and power tests. Body mass, each component of somatotype, maximal anaerobic power developed on a cycle ergometer, and isokinetic knee extension strength correlated significantly with individual scrummaging force. A regression model (P < 0.001) including body mass, mesomorphy, maximal anaerobic power and hip angle while in the scrummaging position accounted for 45% of the variance in individual scrummaging force. The packs that produced the largest scrummaging forces were, in general, characterized by a greater pack force to sum of individual force ratio than the packs producing lower forces. Our results emphasize the need for a scrum pack to develop technique and coordination as a unit to maximize scrummaging force.  相似文献   
940.
This paper explores the association between moderate levels of physical activity (PA) and health benefits in well being and symptoms such as tiredness, back pain, and constipation. Participants in the Australian Longitudinal Study on Women's Health, 14,502 young women (ages 18-23 years), 13,609 middle-age women (45-50 years), and 11,421 older women (ages 70-75 years), answered questions about vigorous and less vigorous exercise (used to determine a physical activity score), well being (SF-36), symptoms, and medical conditions. There were significant associations between the PA score and SF-36 in each cohort. Odds ratios (OR) for a range of symptoms and conditions were lower for women who reported low to moderate activity than for sedentary women, for example, for young women or for constipation = 0.76 (CI, 0.65-0.89), for middle-age women or for tiredness = 0.70 (0.63-0.78). There was no threshold of PA at which health benefits increased significantly. Although cross-sectional, the findings suggest that low-to-moderate levels of exercise are associated with a range of health benefits for women of all ages. These preliminary findings will be followed up during the longitudinal study.  相似文献   
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