The effect of video-feedback on the learning of the tennis service by intermediate players     

P C Van Wieringen  H H Emmen  R J Bootsma  M Hoogesteger  H T Whiting 《Journal of sports sciences》1989,7(2):153-162

Effects of video-feedback on improvement of the tennis service were investigated in subjects having at least 2 years of playing experience in tennis. The experiment was carried out in an indoor tennis hall under normal training conditions. Subjects were randomly divided into three groups: a video-feedback training (VFT) group, a traditional training (TT) group and a control group, each consisting of 22 subjects. While the subjects of the control group received no training at all, subjects in both the VFT and TT groups were trained twice weekly during 5 consecutive weeks. Each training session lasted 40 min, of which 30 min was spent on actual practice in training of the service. The remaining 10 min was spent on watching, analysing and discussing video recordings of either their own service performed during the training session (VFT group), or ground strokes and volleys of top level players (TT group). Both the VFT and TT group showed significantly greater improvements in both achievement scores and form (technique) scores than did the control group. No differences, however, could be demonstrated between the VFT and TT group, indicating that the subjects of the former group did not benefit from the video-feedback they received. While form scores correlated significantly (P less than 0.001) with the velocity of the served ball, no such relation between form scores and spatial accuracy was apparent.  相似文献   

Health locus of control predicts free-living, but not supervised, physical activity: a test of exercise-specific control and outcome-expectancy hypotheses     

R K Dishman  M Steinhardt 《Research quarterly for exercise and sport》1990,61(4):383-394

We statistically controlled fitness (1.5-mile run), outcome-expectancy values, and perceived barriers for physical activity and then compared internal health locus of control (IHLOC) with internal exercise locus of control (IEXLOC) for predicting the physical activity of college students (N = 84). Prospective observations of self-reported free-living physical activity (seven-day recall) and supervised running (time x distance) were made at 2-, 5-, and 9-week intervals. IHLOC predicted seven-day recall at Week 2 (beta = .19) and Week 5 (beta = .36) (increase in adjusted R2 ranged from .05 to .12, p less than .05). Consistent with theory, the prediction was not reproducible when generalized outcome-expectancy value rather than outcome-expectancy value for health was assessed. IHLOC was unrelated to supervised running. IEXLOC was unrelated to activity in all analyses, even though exercise-specific measures of outcome-expectancy values (beta s = .20) and perceived barriers (beta s = .27-.32) predicted both seven-day recall and supervised running (p less than .05). IHLOC also discriminated (p less than .05) high active and low active subjects when criterion groups were formed from population norms on seven-day recall (greater than or less than 280 kcal.kg-1.week-1). Results indicate that tests of decision theories that include locus of control measures specific to health or exercise must adjust for fitness, perceived barriers to physical activity, and behaviorally relevant outcome-expectancy values of physical activity when studying college students. The construct validity of exercise locus of control remains uncertain for college students.  相似文献   

The teaching of religion     

M.L. Jacks M.A. 《British Journal of Religious Education》1935,2(1):9-13

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Why Light in the Library or Comments on Illumination     

Stecher RM 《Bulletin of the Medical Library Association》1947,35(3):137-145

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Durability of cement drain tile and concrete in alkali soils; third progress report (1919–1920)     

G.M. Williams 《Journal of The Franklin Institute》1922,194(2):245-247

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Dust showers     

Washington Jones  W Barnet Le Van  Tinius Olsen  William M Henderson  Wm.D Marks 《Journal of The Franklin Institute》1880,110(2):106-114

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Improvement of the geophone by electrical sound amplifiers     

Walter T. Ackley  Clifton M. Ralph 《Journal of The Franklin Institute》1924,198(6):834-835

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Washability of fine sizes of coal on tables,with particular reference to Washington and Alaskan coals     

Byron M. Bird 《Journal of The Franklin Institute》1927,204(2):273-274

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Lecture-notes on physics     

Alfred M. Mayer 《Journal of The Franklin Institute》1867,84(5):321-329

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A season-long team-building intervention: examining the effect of team goal setting on cohesion     

Senécal J  Loughead TM  Bloom GA 《运动与训练心理学杂志》2008,30(2):186-199

The purpose of the current study was to determine whether the implementation of a season-long team-building intervention program using team goal setting increased perceptions of cohesion. The participants were 86 female high school basketball players from 8 teams. The teams were randomly assigned to either an experimental team goal-setting or control condition. Each participant completed the Group Environment Questionnaire (GEQ; Carron, Brawley, & Widmeyer, 2002; Carron, Widmeyer, & Brawley, 1985), which assessed cohesion at both the beginning and end of the season. Overall, the results revealed a significant multivariate effect, Pillai's trace F(12, 438) = 2.68, p = .002. Post hoc analyses showed that at the beginning of the season, athletes from both conditions did not differ in their perceptions of cohesion. However, at the end of the season, athletes in the team goal-setting condition held higher perceptions of cohesion than athletes in the control condition. Overall, the results indicated that team goal setting was an effective team-building tool for influencing cohesiveness in sport teams.  相似文献