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51.
52.
Purpose: The aim of this study was to examine the effect of active versus passive recovery on 6 repeated Wingate tests (30-s all-out cycling sprints on a Velotron ergometer). Method: Fifteen healthy participants aged 29 (SD = 8) years old (body mass index = 23 [3] kg/m2) participated in 3 sprint interval training sessions separated by 3 to 7 days between each session during a period of 1 month. The 1st visit was familiarization to 6 cycling sprints; the 2nd and 3rd visits involved a warm-up followed by 6 30-s cycling sprints. Each sprint was followed by 4 min of passive (resting still on the ergometer) or active recovery (pedaling at 1.1 W/kg). The same recovery was used within each visit, and recovery type was randomized between visits. Results: Active recovery resulted in a 0.6 W/kg lower peak power output in the second sprint (95% confidence interval [CI] [ ? 0.2, ? 0.8 W/kg], effect size = 0.50, p < .01) and a 0.4 W/kg greater average power output in the 5th and 6th sprints (95% CI [+0.2,+0.6 W/kg], effect size = 0.50, p < .01) compared with passive recovery. There was little difference between fatigue index, total work, or accumulated work between the 2 recovery conditions. Conclusions: Passive recovery is beneficial when only 2 sprints are completed, whereas active recovery better maintains average power output compared with passive recovery when several sprints are performed sequentially (partial eta squared between conditions for multiple sprints = .38).  相似文献   
53.
This study examined whether differences in waist circumference (WC) and pedometer placement (anterior vs. midaxillary vs. posterior) affect the agreement between pedometer and observed steps during treadmill and self-paced walking. Participants included 19 pairs of youth (9–15 years old) who were matched for sex, race, and height and stratified by WC (high WC: HWC; low WC: LWC). Participants performed 3-min treadmill-walking trials at speeds of 59, 72, and 86 m·min-1 and a 400-m self-paced walking trial on level ground. Bland-Altman plots were used to assess the agreement between pedometer and observed steps of spring-levered pedometers by WC, pedometer placement, and walking speed. In the HWC group, the posterior pedometer placement consistently agreed most closely with observed steps at all treadmill speeds and during self-paced walking. In the LWC group, no single pedometer placement consistently agreed most closely with observed steps at all treadmill speeds and during self-paced walking. We conclude that a posterior pedometer placement improves step-count accuracy in most youth with an HWC at a range of walking speeds on level ground.  相似文献   
54.
The aims of this study were to examine and compare selected physiological and metabolic responses of wheelchair athletes in two paraplegic racing classes [T3: n = 8 (lesion levels T1-T7; paraplegics); T4: n = 9 (lesion levels below T7; paraplegics)] to prolonged exercise. In addition, we describe the responses of three tetraplegic athletes [T2: n = 3 (lesion levels C6/C7: tetraplegics)]. Twenty athletes completed 90 min of exercise at 75% VO2peak on a motorized treadmill adapted for wheelchairs. The mean (+/- s) heart rates of the T3 and T4 racing classes were 165 +/- 2 and 172 +/- 6 beats.min-1, respectively. For the T4 racing class, heart rate gradually increased during the test (P < 0.05), whereas for the T3 racing class, heart rate reached a plateau after an initial increase. The mean heart rate of the tetraplegics was 114 +/- 3 beats.min-1. The T3 and T4 classes exhibited similar respiratory exchange ratios, plasma lactate and glucose concentrations throughout the test. For both the T3 and T4 racing class, free fatty acid, glycerol, ammonia, urea and potassium concentrations had increased from resting values by the end of the test (P < 0.05). In conclusion, the results of this study suggest that endurance-trained wheelchair athletes are able to maintain velocities equivalent to the same relative exercise intensity (75% VO2peak) for prolonged periods irrespective of lesion level.  相似文献   
55.
The aim of this study was to examine the effect of intermittent high-intensity shuttle running and fluid ingestion on the performance of a soccer skill. Nine semi-professional soccer players volunteered to participate in the study. Their mean (± sx ) age, body mass and maximal oxygen uptake were 20.2 ± 0.4 years, 73.2 ± 1.8 kg and 59.1 ± 1.3 ml·kg-1 ·min-1 respectively. The players were allocated to two randomly assigned trials: ingesting or abstaining from fluid intake during a 90 min intermittent exercise protocol (Loughborough Intermittent Shuttle Test:LIST).This test was designed to simulate the minimum physical demands faced by soccer players during a game. Before and immediately after performance of the test,the players completed a soccer skill test and a mental concentration test. Performance of the soccer skill test after the 'no-fluid' trial deteriorated by 5% (P ? 0.05),but was maintained during the fluid trial. Mean heart rate, perceived exertion, serum aldosterone, osmolality, sodium and cortisol responses during the test were higher (P ? 0.05) in the 'no-fluid' trial than in the fluid trial. The results of this study suggest that soccer players should consume fluid throughout a game to help prevent a deterioration in skill performance.  相似文献   
56.
Minimal research papers have investigated the use of student evaluations on the laboratory, a learning medium usually run by teaching assistants with little control of the content, delivery and equipment. Finding the right mix of teaching assistants for the laboratory can be an onerous task due to the many skills required including theoretical and practical know-how, troubleshooting, safety and class management. Using larger classes with multiple teaching assistants, a team-based teaching (TBT) format may be advantageous. A rigorous three-year study across twenty-five courses over repetitive laboratory classes is analysed using a multi-level statistical model considering students, laboratory classes and courses. The study is used to investigate the effectiveness of the TBT format, and quantify the influence each demonstrator has on the laboratory experience. The study found that TBT is effective and the lead demonstrator most influential, influencing up to 55% of the laboratory experience evaluation.  相似文献   
57.
Path analyses revealed that one's tendency to conceal distressing information, social support, psychological distress, and attitudes toward seeking help predicted intended use of counseling services for college students who had and had not previously been in counseling. Prospective analyses revealed that attitudes toward seeking help predicted actual use of the campus counseling center. These findings have implications for campus outreach programs and in‐session work with clients.  相似文献   
58.
Assisted conception is becoming an increasingly more common treatment option for women and couples who experience fertility problems. Links have been made in the literature between assisted conception and a greater incidence of pregnancy or birth complications, low birth weight or premature babies, and babies with congenital abnormalities. In addition, evidence suggests that the experience of assisted conception may influence the development of early mothering relationships and impact parenting adjustment. Although this commentary article does not strategically review all available literature, it provides an overview of the health issues that women and families undergoing assisted conception have experienced or may experience. Through raising awareness and promoting discussion of these issues, practitioners will be better equipped to provide informed education and support.  相似文献   
59.
Previously we showed how we measured pedagogy and revealed its association with learning outcomes of sixth‐form college mathematics students. In this project we followed a similar approach to the study of university transition. We particularly sought to identify the students’ perceptions of the transitional experience, and measure the association with learning outcomes. We drew on longitudinal surveys of students entering different programmes in five universities. Following them into their first year or so, allowed us to track their ‘disposition to complete the course’ and their ‘disposition to study more mathematics’, inter alia. We developed and validated two ‘fit‐for‐purpose’ measures of students’ perception of their transition, one we call ‘perception of the transitional gap/jump’ and one we call ‘degree of positive feeling about the transition’. We report some statistically and educationally significant associations between these and the students’ developing dispositions, and discuss the prospects for this approach to studying transition.  相似文献   
60.
Concern has been expressed about the vulnerability of the ‘academic profession’ as a consequence of threats from productivism, managerialism and the like (Beck and Young, Br J Sociol Educ 26(2):183–197, 2005). I question the apparent self-understanding of academe as a profession. Referring to thinking from higher education (Barnett, High Educ 40:409–422, 2000a; Educ Phil Theor 32(3):319–326, 2000b; Realizing the University in an age of supercomplexity, 2000c; Stud High Educ 25(3):255–265, 2000d; Lond Rev Educ 2(1):61–73, 2004a; Piper, Are professors professional? The organisation of University examinations, 1994; Taylor 1999), and from the sociology of the professions (in particular Evetts, Int J Sociol Soc Policy 23(4/5):22–35, 2003a; Int Sociol 18(2):395–415 2003b; Curr Sociol 54(1):133–143 2006a; Curr Sociol 54(4):515–531, 2006b), I propose that significant shifts in self-understanding and practice are needed for academe to claim a social role as a ‘profession’.  相似文献   
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