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61.
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   
62.
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   
63.
This study was designed to examine the role of foot type, height, leg length, and range of motion (ROM) measurements on excursion distances while performing the Star Excursion Balance Test (SEBT), a test of dynamic postural control. Participants (n = 30) performed 3 trials of the SEBT in each of the 8 directions while balancing on the right and left legs. No statistically significant relations were found between foot type or ROM measurements and excursion distances with the SEBT. Significant correlations were revealed between height and excursion distance and leg length and excursion distance with leg length having the stronger correlation. Using raw excursion measures, males were found to have significantly greater excursion distances than females; however, after normalizing excursion distances to leg length, there were no significant differences related to gender. In conclusion, when using the SEBT for experimental or clinical purposes, participants' excursion distances should be normalized to leg length to allow for a more accurate comparison of performance among participants.  相似文献   
64.
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   
65.
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   
66.
Abstract

Little evidence exists to assess the effects of dance training on special populations. Research in this field has relied on pretest-posttest methods for gathering data. While such data gathering methods may be appropriate for particular research problems, alone they may be inadequate for broad-based, exploratory investigations of programs and effects. The present study is an example of a multiple measurement approach that uses eight measurements, in combination, to answer four research questions regarding the physical and social effects that occur when a group of educable mentally retarded adolescents is exposed to a 10-week dance program. The findings revealed that four students showed improvement in both social and physical behaviors, seven students showed improvement in either social or physical behaviors, and two students showed no improvement. There was no evidence of a “transfer effect” due to participation in the program, and some students' behaviors were affected by external factors. The authors found the approach useful for identifying multiple effects and generating hypotheses for further study.  相似文献   
67.
Texts     
Made in America: Immigrant Students in Our Public Schools. Laurie Olsen, New York: The New Press, 1997, 276 pages, $25.00 (hardcover), ISBN 1–5658–4400–9, and $14.95 (softcover), ISBN 1–5658–4471–8.

The Power of Their Ideas: Lessons for America From a Small School in Harlem. Deborah Meier, Boston: Beacon Press, 1995, 190 pages, $12.00 (softcover). ISBN 0–8070–3111–9.

Yesterday, Today & Tomorrow: Meeting the Challenge of Our Multicultural America & Beyond. Paul D. Christiansen and Michelle Young, San Francisco: Gaddo Gap Press, 1996, 376 pages, $29.95 (softcover). ISBN 1–8801–9218–7.  相似文献   
68.
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   
69.
70.
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   
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