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This study examined the influence of the challenge level of to-be-learned stimulus on learning strategies in novice and advanced dancers. In Study 1, skill-level appropriate dance routines were developed for novice and advanced jazz dancers. In Study 2, 8 novice and 9 advanced female jazz dancers attempted to learn and remember the two routines in mixed model factorial design, with one between-participants factor: skill level (novice or advanced) and two within-participants factors: routine (easy or difficult) and performance (immediate or delayed). Participants were interviewed regarding the strategies used to learn and remember the routines. Results indicated that advanced performers used atypical learning strategies for insufficiently challenging stimuli, which may reflect characteristics of the stimuli rather than the performer. The qualitative data indicate a clear preference of novice and advanced performers for spatial compatibility of stimuli and response.  相似文献   
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There is little research on students' engagement in physical activity in middle school physical education (PE). We observed student activity, lesson context, and teacher behavior in 430 PE lessons taught by 126 teachers in 24 schools. Variables were analyzed by mixed-model nested analyses of covariance. Boys were more active than girls overall and during skill drills, game play, and free play. Student activity varied by lesson context, with fitness activities producing the most activity. Class size was negatively associated with student activity. Daily PE contributed a weekly total of 25 min of vigorous activity and 83 min of moderate-to-vigorous activity--much less than national objectives. Results suggest that numerous opportunities exist for increasing student physical activity during middle school PE.  相似文献   
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This study examined the relationships among social factors, individual differences, intrinsic motivation, and effort and persistence in the physical education context using cognitive evaluation theory as a framework. Female (n = 201) and male (n = 206) high school students completed measures of motivational climate, teaching style, perceived competence, self-determination, goal orientations, and intrinsic motivation. Teachers rated the students on effort and persistence in the class activities. Hypothesized relationships among the variables were tested using structural equation modeling. Results revealed that perceived competence and goal orientations directly predicted intrinsic motivation and mediated the effects of motivational climate and teaching style on intrinsic motivation. Intrinsic motivation directly predicted effort and persistence. Task goal orientation mediated the effects of learning climate on perceived competence and self-determination. The strongest predictors of intrinsic motivation and effort and persistence were task goal orientation perceived competence, and learning climate.  相似文献   
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It has previously been shown that females incur less muscle damage than males after strenuous exercise, but limited data are available for humans. To determine possible differences between the sexes in humans, the response to high-force eccentric exercise was examined in a large sample of women (n = 83) and men (n = 82). The participants performed a bout of eccentric exercise of the elbow flexors consisting of 70 maximal repetitions. Isometric strength, resting elbow angle and muscle soreness were measured before, immediately after (except soreness) and then daily for 7 days after exercise. There was a significant loss in strength among both groups (69% for women and 63% for men) (P < 0.01) immediately after exercise; at 168 h post-exercise, women still had a 27% strength loss and men had a 24% strength loss. No significant difference in strength loss or recovery rate was found between men and women. Soreness reached peak values 32-48 h post-exercise (P < 0.01), with no significant difference between men and women. Range of motion decreased significantly until 3 days after exercise (14.6 degrees or 0.255 rad loss for women; 12.2 degrees or 0.213 rad loss for men) (P < 0.01); at 168 h post-exercise, the women and men still showed a loss of 4.8 degrees (0.084 rad) and 4.0 degrees (0.07 rad), respectively. There was a significant interaction of sex x time (P < 0.01); a post-hoc test indicated that the women experienced a greater loss in range of motion at 72 h than men and this difference was maintained to 168 h post-exercise (P < 0.01). Thus, our results do not support the contention that women have a lower response to eccentric exercise than men.  相似文献   
956.
Forty-nine previously sedentary or low active individuals aged 40-71 years were allocated to three groups. The long walking group participated in an 18-week walking programme which consisted of walks lasting 20-40 min; the repetitive short walking group completed walks of between 10 and 15 min, up to three times a day, with no less than 120 min between each walk; and the control group maintained their low level of activity. Both walking programmes began at a prescribed 60 min x week(-1), which increased steadily up to 200 min x week(-1) by week 12. During the study, the long walking group walked for an estimated 2514 min (139 min x week(-1)), expending an estimated 67.5 MJ (3.72 MJ x week(-1)) at an estimated 73% of their age-predicted maximum heart rate and 68% of their estimated VO2max. The repetitive short walking group walked for an estimated 2476 min (135 min x week(-1)), expending an estimated 58.5 MJ (3.17 MJ x week(-1)) at an estimated 71% of their age-predicted maximum heart rate and 65% of their estimated VO2max. The results showed a statistically significant reduction in heart rate during a standardized step test (pre- vs post-intervention) in both walking groups, indicating an improvement in aerobic fitness, although the control group showed a higher average heart rate during the post-intervention test, indicating reduced fitness. When compared with the male subjects pre-intervention, the females possessed more favourable levels of high-density lipoprotein (HDL) cholesterol (P< 0.001), apolipoprotein (apo) AI (P < 0.001) and ratios of total cholesterol:HDL cholesterol (P< 0.02) and low-density lipoprotein (LDL) cholesterol: HDL cholesterol (P< 0.02). Compared with the controls post-intervention, the walking groups showed no statistically significant changes in total cholesterol, LDL cholesterol, HDL cholesterol, apo AI, apo AII, apo B, or the ratios of total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol, apo AI: apo B or apo AI: apo AII (P > 0.05). Relative to the walking groups, factor XIIa increased in the control group (P < 0.05). We conclude that, although both walking programmes appeared to improve aerobic fitness, there was no evidence of improvements in the blood lipids or associated apolipoproteins of the walking groups. Further analysis indicated that this apparent lack of change may have been related to the subjects' relatively good pre-intervention blood lipid profiles, which restricted the potential for change. The implications of the observed changes in the coagulation/fibrinolytic factors remain unclear.  相似文献   
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