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This study examined how activity type influenced heart rates and time spent in target heart rate zones of high school students participating in physical education classes. Significantly higher average heart rates existed for fitness (142 +/- 24 beats per minute [bpm]) compared to team (118 +/- 24 bpm) or individual (114 +/- 18) activities. Similar results occurred for the percentage of activity time spent within a target heart rate zone (fitness 81.7 +/- 15.9%, individual 68.4 +/- 30.5%, and team 60.6 +/- 30.5%). Boys attained higher heart rates during team activities, while female students had higher rates during individual activities indicating male and female adolescents respond differently to activity types. The highest mean heart rates were observed during fitness activities. 相似文献
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Stephen P Bailey Laureen Brown Elizabeth K Bailey 《Cardiopulmonary Physical Therapy Journal》2008,19(1):3-10
Individuals with chronic obstructive pulmonary disease (COPD) have been shown to benefit from participation in pulmonary rehabilitation (PR) programs that include exercise training and education. Purpose: To examine the relationship between improvements in 6 minute walk distance and perceived quality of life in individuals with COPD following completion of a PR program. Methods: The records of 139 individuals completing a PR program (3 times a week for 8 weeks) were retrospectively examined. Prior to entry and upon completion of the program each individual completed a 6 minute walk test (6MWT), the SF-36 Health survey, and the UCSD Shortness of Breath Questionnaire (SOB). SF-36 results were analyzed according to 8 subscales [Physical Functioning (PF), Role Physical (RF), Bodily Pain (BP), General Health (GH), Vitality (V), Social Functioning (SF), Role Emotional (RE), and Mental Health (MH)]. Results: PR resulted in significant improvements in 6MWTdistance (Pre = 845 ± 37 ft, Post = 1127 ± 32 ft, p < 0.001), PF (p < 0.001), RF (p = 0.001), Vitality (p = 0.002), SF (p < 0.001), RE (p = 0.037), MH (p < 0.001) and SOB (Pre = 53 ± 2, Post = 47 ± 2, p < 0.001). The change in 6MWT distance was not related to changes in PF (r = 0.17), RF (r = 0.03), GH (r = 0.03), Vitality (r = −0.001), SF (r = 0.01), RE (r = 0.06), MH (r = −0.04) or SOB (r = 0.12). The magnitude of improvement in 6MWT distance (68%) was much greater than that observed in PF (15%), RF (16%), GH (6%), VT (18%), SF (20%), RE (14%), MH (14%), or SOB (8%). Conclusions: PR has a positive impact on 6 minute walk distance and perceived quality of life in individuals with COPD; however, changes in 6 minute walk distance appear to have no relationship to changes in perceived quality of life. 相似文献
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It is often desirable to represent carrier distribution systems by networks so that analysis can be made to predict the behavior of these systems. Modeling of two canonical carrier distribution systems, the star-shaped system and the parallel-wire system by networks was carried out in this paper. The representation is given in terms of lumped parameters when the lengths of the carrier lines are short and it is given in terms of lumped and distributed parameters when the lengths of the carrier lines are long. 相似文献
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Mary A. Anderson Frank Bowles C. O. Taiwo Jan D. Beckmann L. J. Lewis James R. Liesch Godfrey N. Brown H. L. Elvin Shib K. Mitra Richard F. Behrendt Graeme Kemelfield Hugh W. R. Hawes W. A. Dodd A. L. Tibawi 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1971,17(2):220-251