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71.
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   
72.
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   
73.
Improving children's attendance is a high priority for Head Start and other early childhood education programs serving low-income children. We conducted a randomized control trial in a major northern city to evaluate the impact of a low-cost intervention designed to promote parents' social capital as a potential influence on children's attendance in Head Start centers. The intervention assigned children to treatment group classrooms based on (a) neighborhood of residence (geography condition) or (b) the geography condition plus the opportunity for parents to form partnerships in support of their children's attendance, or to control group classrooms according to Head Start guidelines only. We did not find impacts on average attendance throughout the year. However, the intervention did lead to increased attendance during the winter when average center attendance was lowest. There were no impacts on fall or spring attendance. Follow-up exploratory analyses of focus groups with parents and staff suggested that parents' level of connection and trust, self-generated partnership strategies, and commitment to their children's education may be factors by which parents' social capital expands and children's attendance improves.  相似文献   
74.
This investigation utilized an integrative model of development for ethnic minority children and a process model of engagement to explore whether three dimensions of school engagement (behavioral, emotional, and cognitive) mediated relationships between school racial climate, academic performance, and educational aspirations. A total of 139 African American students were recruited from a high school in the southeastern United States. Findings revealed an indirect association between perceptions of racial fairness and academic achievement indicators through behavioral and cognitive engagement. Behavioral and cognitive engagement also mediated relationships between youths’ perceived peer discrimination and academic achievement indicators. No significant indirect associations between teacher discrimination and academic achievement through school engagement dimensions were found. Study limitations, future directions, and implications are discussed.  相似文献   
75.
76.
This study examines the relationship between phonological awareness (PA) in the two languages of Korean English as a foreign language learning children in relation to L1 characteristics and school experiences, and its predictive role in word decoding skills in each language. Seventy-two 5?C6-year-old Korean children who had attended English-medium preschools and kindergartens for at least 18?months were tested on a range of PA and emergent literacy skill measures in both Korean (L1) and English (L2). The findings indicate that the phonological representations of the participants reflect more of the L1, rather than school language, characteristics. In addition, L1 PA, syllable and phoneme awareness in particular, was predictive of L2 decoding abilities after accounting for L2 PA and emergent literacy skills. The results are discussed in terms of language-specific L1 phonological and orthographic characteristics, as well as their L2-learning contexts.  相似文献   
77.
Drawing from ethnographic data, this paper explores how African American male teachers working with African American male students performed their pedagogy. This paper highlights how teachers’ understanding of African American males social and educational needs shaped their pedagogical performance. Interestingly however, teachers’ performance was contingent on the diverse ways they imagined African American males should engage within their social and political worlds. These findings suggest then that African American male teachers’ pedagogic performances were both complex and multifaceted.  相似文献   
78.
79.
The present study was designed to investigate the nature, timing, and correlates of motivational change among a large sample (N = 1051) of third- through eighth-grade students. Analyses of within-year changes in students’ motivational orientations revealed that both intrinsic and extrinsic motivations decreased from fall to spring, with declines in intrinsic motivation especially pronounced for the adolescents and declines in extrinsic motivation especially pronounced for the elementary students. These changes in motivation were explained, in part, by shifts in students’ perceptions of the school goal context. Findings suggested that typical age-related declines in intrinsic motivation may be minimized by a school-wide focus on mastery goals. Finally, the potential academic consequences of students’ motivational orientations were examined with a series of hierarchical multiple regressions. Intrinsic motivation and classroom achievement appeared to influence one another in a positive and reciprocal fashion. Poor classroom performance minimally predicted higher levels of extrinsic motivation, but extrinsic motivation was not a source of low classroom grades.  相似文献   
80.
Studies with adults suggest that implicit preferences favoring White versus Black individuals can be reduced through exposure to positive Black exemplars. However, it remains unclear whether developmental differences exist in the capacity for these biases to be changed. This study included 369 children and examined whether their implicit racial bias would be reduced following exposure to positive Black exemplars. Results showed that children's implicit pro‐White bias was reduced following exposure to positive Black exemplars, but only for older children (Mage = ~10 years). Younger children's (Mage = ~7 years) implicit bias was not affected by this intervention. These results suggest developmental differences in the malleability of implicit racial biases and point to possible age differences in intervention effectiveness.  相似文献   
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