Differences in the Intensity and Duration of Adolescents' Sports and Exercise Across Physical and Social Environments

We used data from the American Time Use Survey (years 2003–06) to analyze whether the intensity and duration of high school students' (ages 15–18 years) sports and exercise bouts differed across physical and social environments. Boys' sports and exercise bouts were more likely to reach a vigorous intensity when taking place at school and with friends/acquaintances/other people; whereas girls' sports and exercise bouts were more likely to reach a vigorous intensity when outdoors and alone. For boys and girls, bout durations were greater at school and with friends/acquaintances/other people than in other environments. Overall, environmental influences on the intensity but not duration of sports and exercise bouts appear to differ between boys and girls.     

A physiological and biomechanical comparison of over-ground,treadmill and ergometer wheelchair propulsion

Abstract

The purpose of the study was to determine which laboratory-based modality provides the most valid physiological and biomechanical representation of over-ground sports wheelchair propulsion. Fifteen able-bodied participants with previous experience of wheelchair propulsion performed a 3-minute exercise trial at three speeds (4, 6 and 8 km ? h^–1) in three testing modalities over separate sessions: (i) over-ground propulsion on a wooden sprung surface; (ii) wheelchair ergometer propulsion; (iii) treadmill propulsion at four different gradients (0%, 0.7%, 1.0% and 1,3%). A 0.7% treadmill gradient was shown to best reflect the oxygen uptake (7.3 to 9.1% coefficient of variation (CV)) and heart rate responses (4.9 to 6.4% CV) of over-ground propulsion at 4 and 6 km ? h^–1. A 1.0% treadmill gradient provided a more valid representation of oxygen uptake during over-ground propulsion at 8 km ? h^–1 (8.6% CV). Physiological demand was significantly underestimated in the 0% gradient and overestimated in the 1.3% gradient and wheelchair ergometer trials compared to over-ground trials (P<0.05). No laboratory-based modality provided a valid representation of the forces applied during OG (≥ 18.4% CV). To conclude, a 0.7% treadmill gradient is recommended to replicate over-ground wheelchair propulsion at lower speeds (4 and 6 km ? h^–1) whereas a 1.0% gradient may be more suitable at 8 km ? h^–1.     

High-intensity interval running is perceived to be more enjoyable than moderate-intensity continuous exercise: Implications for exercise adherence

Abstract

The aim of this study was to objectively quantify ratings of perceived enjoyment using the Physical Activity Enjoyment Scale following high-intensity interval running versus moderate-intensity continuous running. Eight recreationally active men performed two running protocols consisting of high-intensity interval running (6×3 min at 90% [Vdot]O_2max interspersed with 6×3 min active recovery at 50% [Vdot]O_2max with a 7-min warm-up and cool down at 70% [Vdot]O_2max) or 50 min moderate-intensity continuous running at 70% [Vdot]O_2max. Ratings of perceived enjoyment after exercise were higher (P < 0.05) following interval running compared with continuous running (88 ± 6 vs. 61 ± 12) despite higher (P < 0.05) ratings of perceived exertion (14 ± 1 vs. 13 ± 1). There was no difference (P < 0.05) in average heart rate (88 ± 3 vs. 87 ± 3% maximum heart rate), average [Vdot]O₂ (71 ± 6 vs. 73 ± 4%[Vdot]O_2max), total [Vdot]O₂ (162 ± 16 vs. 166 ± 27 L) or energy expenditure (811 ± 83 vs. 832 ± 136 kcal) between protocols. The greater enjoyment associated with high-intensity interval running may be relevant for improving exercise adherence, since running is a low-cost exercise intervention requiring no exercise equipment and similar relative exercise intensities have previously induced health benefits in patient populations.     

乡愁

我的脑子不止一次被心理学家称为的老屋妄想症所麻痹。我和妻子买了一栋老房子,包含所有老房子存在的问题,例如白蚁,     

Self-regulating academic learning and achievement: The emergence of a social cognitive perspective

For three decades, social cognitive researchers have studied children's development of self-regulation as an achievement of socialization processes. I recount historically the emergence of a social cognitive perspective on self-regulation and identify its unique features. Two essential characteristics of students' self-regulated academic learning have been identified — their use of strategies and perceptions of self-efficacy. A social cognitive model of academic self-regulated learning is proposed that integrates triadic determinants of self-regulated learning (personal, behavioral, and environmental) on the basis of a strategic control loop. When students monitor their responding and attribute outcomes to their strategies, their learning becomes self-regulated, and they display increased self-efficacy, greater intrinsic motivation, and higher academic achievement.     

A cross-national mixed-method study of reality pedagogy

This mixed-methods cross-national study investigated the effectiveness of reality pedagogy (an approach in which teachers become part of students’ activities, practices and rituals) in terms of changes in student perceptions of their learning environment and attitudes towards science. A questionnaire was administered to 142 students in grades 8–10 in the Bronx, New York City and Dresden, Germany. The questionnaire combines learning environment scales from the Constructivist Learning Environment Survey and the What Is Happening In this Class? Questionnaire with attitude scales from the Test of Science-Related Attitudes. Student interviews were used to support questionnaire findings. Quantitative data analyses revealed that reality pedagogy had a greater impact on students in the Bronx than in Dresden, with qualitative data clarifying differences in how reality pedagogy was enacted in each geographic area. Overall, our findings add to the body of evidence concerning the effectiveness of reality pedagogy as an approach to teaching and learning science across a variety of contexts.     

Variables related to career commitment,mastery motivation,and level of career aspiration among college students

The authors wish to express appreciation for the statistical help provided by James Wardrop and Ya-Mei Chen; and for the support provided by the Bureau of Educational Research and the Campus Research Board, University of Illinois. Also several persons helped with the development of the measures and data collection including Carole Ames, Mary Z. Anderson, Cindy Glidden, Fu-lin Y. Lee, Kirsten Peterson, and Barbara Powell. Requests for reprints may be addressed to the first author at the Educational Psychology Department, University of Illinois, 1310 South Sixth St., Champaign, IL 61820.     

Differential Effectiveness of Computer-assisted Instruction for Boys and Girls

A sample of 671 secondary school students in 24 classes of nominally slow learners was involved in investigating not only the relative efficacy of computer-assisted instruction (CAI) and traditional expository teaching, but particularly the differential effectiveness of the two teaching methods for boys and girls. Both achievement and attitude outcomes were investigated. The difference in mean scores between CAI and traditional classes overall was 3.5 standard deviations for achievement and 1.4 standard deviations for attitude. However, although there was no overall effect of gender on either outcome, a significant treatment-gender interaction occurred for the achievement outcome (but not for the attitude outcome). Boys achieved better than girls in the CAI groups, but boys and girls achieved similarly in the control group.     

Relationship between perceived levels of classroom individualization and science-related attitudes

Relationships between perceived levels of classroom individualization and science-related attitudes were explored for a sample of 712 junior high school science students. Five dimensions of perceived individualization (personalization, participation, independence, investigation, and differentiation) were measured with the Individualized Classroom Environment Questionnaire (ICEQ), while seven distinct attitudes were measured with the Test of Science-Related Attitudes (TOSRA). Hierarchical regression analyses revealed that the set of individualization variables accounted for a significant increment in end-of-year attitude scores, beyond that attributable to corresponding beginning-of-year attitude scores, for four of the seven attitudes considered. Significant associations between an individual individualization variable and an attitudinal dimension were positive in all cases. The study also provided support for the reliability and validity of the ICEQ and TOSRA and for their general usefulness in science education research.