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1.
Abstract

The decay of the memory trace for intervals of 1/2 min., 1 1/2 min., and 4 min. between the test stimulus and the reproduction trial was studied for a force reproduction task in which the amount of movement was very small, .13 in. The subject pushed against a handle attached to the top of a steel bar with the preferred hand. Sixty-three women volunteers from college physical education classes performed the experiment. For Part A all subjects first had four trials in which the reproduction was immediate (the control condition). Then they were divided randomly into three subgroups of 21, and each subgroup was assigned to one of the three retention intervals (experimental conditions) for four more trials. In Part B the whole experiment was repeated. For both absolute and algebraic error, analysis of covariance indicated no significant differences at the .05 level among the experimental conditons. Also, no significant differences were found comparing a condition in Part A with its respective condition in Part B. While there were no significant differences between control and experimental conditions for absolute error, significant differences were found for algebraic error. The algebraic error changed from considerable overestimation upon immediate reproduction to only slight overestimation after a 1/2-min. retention interval.  相似文献   

2.
Abstract

This study was designed to assess the effects of a specifically designed perceptual-motor training program on the level of perceptual-motor development, self-concept, and academic ability of kindergarten children. Subjects for the study were 40 kindergarten children randomly assigned to 1 of 2 groups. Each group received the same kindergarten program with one exception, the experimental group was exposed to a specifically designed perceptual-motor program 30 min daily for 5 mo, while the control group received a free play period for 30 min daily. Results of the study indicated that the data tended to support the specificity of training concept. The variables showing the greatest change were the perceptual-motor tests which measured changes on specific aspects of the training program. There appeared to be some immediate transfer to academic abilities but this was not pronounced enough to suggest that perceptual-motor training was of real benefit in developing academic abilities for normal kindergarten children. In addition the follow-up test indicated no long term effects on academic performance.  相似文献   

3.
Abstract

The effect of attentional focus on the perception of physical work was examined by using a work reproduction design. Subjects performed a fixed interval of work at either 50 or 75% of their predicted VO2 max, during which they were required either to solve a continuous flow of arithmetic problems or to perform in an unfilled control condition. On a subsequent trial, without a concomitant attention-demanding task, subjects were asked to reproduce the amount of work that they had previously performed. It was found that individuals in the control condition produced a significantly greater amount of work on the reproduction trial, while those in the attentional focus condition performed about the same amount as on the previous trial. No interaction was found between attentional focus and work load.  相似文献   

4.
Abstract

Six groups of subjects were tested to determine if various training programs affected performance in speed in swimming 30 yards. No evidence of improvement was found after one group of subjects had been exposed to absolutely no exercise for six weeks and, also, after a group of subjects had participated in various exercises with weights three times weekly for six weeks. Two groups of swimmers who participated in practicing starts, kicking, arm stroking, and sprinting 30 and 60 yards significantly improved their performances in speed in swimming; one group of subjects followed the preceding program three times weekly and another group used the same routine six times a week. Two other groups, one of which was exposed to weight training and swimming, and one of which was exposed only to 30-yard sprints and practicing starts, both showed statistically significant differences in performance.  相似文献   

5.
Abstract

Form A of the Wear Attitude Inventory was administered to one randomly selected physical education class of seventh grade boys, one class of eighth grade boys, and one class of ninth grade boys in each of five junior high schools. The mean Inventory score for each grade was found to be equal to or superior to the mean reported in Wear's validation study. A significant X2 value was found for the distribution of Inventory scores of the three junior high school grades. A biserial coefficient of correlation item analysis which was computed for each of the three grades established that the 30 items correlated significantly with the total score and that the item score also had a significant correlation with the Inventory category score. On the basis of these results, the conclusion was advanced that the Wear Attitude Inventory was an appropriate instrument to measure attitudes of junior high school boys toward physical education.  相似文献   

6.
Purpose: Winning several national championships is an extraordinary feat that very few university coaches have accomplished. The objective of this study was to investigate how some of Canada’s most accomplished university team-sport coaches created and sustained a culture of excellence in their programs. Method: Six university coaches who had won more than 30 national titles participated in this study. Each coach participated in a semistructured interview, and the qualitative data were inductively analyzed using a thematic analysis. Results: The coaches noted that hard work and daily attention to detail, effective emotional management of themselves and their athletes, and continuous self-assessment (self-reflection and seeking mentors) were crucial elements that led to sustained excellence in their programs. Conclusions: This study offers one of the first empirical accounts of how highly successful university coaches developed and maintained a culture of excellence and success in their high-performance sport setting.  相似文献   

7.
ABSTRACT

Purpose: The purpose of this study was to identify whether post-resistance exercise (REx) blood flow restriction (BFR) can elicit a similar acute training stimulus to that offered by either heavy REx or traditional low-load BFR REx. Method: Ten men completed trials with 30% one-repetition maximum (1RM) for 5 sets of 15 repetitions without BFR (30%), with BFR during exercise (30% RD), and with postexercise BFR (30% RP) and at 75% 1RM for 3 sets of 10 repetitions. Lactate and cortisol were measured before and up to 60 min after exercise. Thigh circumference, ratings of perceived exertion (RPE), and pain were measured before and after exercise. Surface electromyography was measured during exercise. Results: All conditions had a large effect (effect size [ES] > 0.8) on lactate, with the largest effects observed with the 75% condition; no differences were observed between the 30% conditions. All conditions had a moderate effect (ES > 0.25 ≤ 0.4) on increasing thigh circumference. This effect was maintained (ES = 0.35) with the application of BFR after REx (30% RP). Change in RPE, from the first to last set, was significantly greater with 30% RD compared with other conditions (all p < .05). Electromyography amplitude was higher and percentage change was greater for the 75% condition compared with the other conditions (both p < .05). Conclusions: The application of BFR immediately post-REx altered several of the responses associated with REx that is aimed at inducing muscular hypertrophy. Additionally, these changes occurred with less pain and perceived exertion suggesting that this form of REx may offer an alternative, tolerable method of REx.  相似文献   

8.
Abstract

The efficiency of two practice schedules was examined on two large muscle motor tasks. There were four groups of subjects (N = 160); each individual in a group performed on one of the two motor tasks under one of the two conditions. Distributed practice consisted of alternating 30-second trials of practice and rest; massed practice was continuous for 8 minutes. Comparisons made during the last minute of practice prior to the rest pause revealed that the massed groups had significant decrements in performance level. In contrast, after the rest period, when both groups were on a distributed schedule, no difference was found in the amount of learning. Learning was found to be a function of the number of trials and independent of the conditions of practice.  相似文献   

9.
Purpose: Brain-derived neurotrophic factor (BDNF) is well known for its potential to promote brain plasticity. It has been proposed that combining cognitive and physical exercise (CCPE) may have the potential to generate more synergistic benefits in cognitive function than either cognitive exercise (CE) or physical exercise (PE) alone. The purpose of this study was to examine acute responses of peripheral BDNF levels and cognitive performance to CE, PE, and CCPE.

Methods: Thirteen healthy adult men participated in four experimental sessions; a 30-min CE, a 30-min cycling PE at an intensity of 60% peak oxygen uptake, a 30-min CCPE at the same intensity as PE, and a 30-min session of complete rest. Plasma BDNF levels and cognitive performance were measured before and after each session.

Results: Both PE and CCPE significantly increased plasma BDNF levels (p?p?≥?.05), and there was no significant difference in peripheral BDNF levels between PE and CCPE (p?≥?.05). No session induced a significant change in cognitive performance (p?≥?.05).

Conclusions: Our study suggests that CE and PE have different responses of peripheral BDNF levels and that CCPE had no additional or synergistic effect on peripheral BDNF levels compared with PE alone. This study offers further insights into the potential mechanisms underlying the respective roles of CE, PE, and CCPE for peripheral BDNF levels and cognitive performance.  相似文献   

10.
Abstract

The study had two aspects: To determine the effect of warm-up throwing drills (employing “systematic overload”) upon subsequent speed and accuracy of the overarm throw in subjects with widely differing maximum velocities, and to determine the effect of a 6-week overload training (in which the speed and accuracy emphases were systematically varied) upon the speed and accuracy of the overarm throw.

The 60 subjects in the short-range phase of the study, examining the immediate effect of overload warm-up, received experimental treatments consisting of 10-oz., 15-oz., and regulation ball warm-up. The 48 subjects who participated in the long-range or training phase of the study received progressive overload in conjunction with various speed and/or accuracy emphases.

Computer services for this study were granted by the University of Wisconsin Research Committee through funds provided by the National Science Foundation and the Wisconsin Alumni Research Foundation.

The results of the study indicated that performance differences in throwing speed and accuracy, of high and low velocity performers that take place immediately following overload warm-up were statistically not significant. The initial speed and/or accuracy emphasis that was given appeared to have little effect on subsequent performance. The results provided no evidence that the use of a weighted ball resulted in immediate or long-range improvements in throwing speed or in throwing accuracy.  相似文献   

11.
Abstract

This study sought to investigate the effect of immediate external feedback on the learning of the golf drive and the 5-iron approach shot. The subjects were 80 university females who met the criterion of rank beginners in golf. They were randomly assigned to a control or an experimental group. The experimental factor was the graph-check-sequence camera used to photograph the movement patterns of each member of the experimental group. The photos were available for the student and instructor to observe performance strengths and weaknesses immediately. The criterion measure was a battery of three golf skill tests. Results were tabulated with a 2 × 2 × 2 factorial design to determine the main effect factors or interaction factors on learning achievement. The only significant F's were methods main effects. Therefore, it was concluded that immediate external feedback through use of the graph-check-sequence camera facilitates the learning of the golf drive and the 5-iron approach shot.  相似文献   

12.
Background:Soccer injuries constitute an important public health problem and cause a high economic burden.Nevertheless,comprehensive data regarding injury costs in nonprofessional soccer are missing.The aim of this study was to determine which groups of nonprofessional soccer athletes,injury types,and injury situations caused high injury costs.Methods:A cross-sectional,retrospective telephone survey was carried out with a random sample of persons who had sustained a soccer injury between July 2013 and June 2014 and who had reported this accident to the Swiss National Accident Insurance Fund(Suva).One year after the corresponding accident,every injury was linked to its costs and to the answers obtained in the interview about injury setting,injury characteristics,and injury causes.Finally,the costs of 702 injuries were analyzed.Results:The average cost of an injury in nonprofessional soccer amounted to€4030(bias-corrected and accelerated 95%confidence interval(BCa 95%CI):3427-4719).Persons aged 30 years and older experienced 35%of soccer injuries but accounted for 49%of all costs.A total of58%of all costs were the result of injuries that occurred during amateur games.In particular,game injuries sustained by players in separate leagues for players aged 30+/40+years led to high average costs of€8190(BCa 95%CI:5036-11,645).Knee injuries accounted for 25%of all injuries and were responsible for 53%of all costs.Although contact and foul play did not lead to above-average costs,twisting or turning situations were highly cost relevant,leading to an average sum of€7710(BCa 95%CI:5376-10,466)per injury.Conclusion:Nonprofessional soccer players aged 30 years and older and particularly players in 30+/40+leagues had above-average injury costs.Furthermore,the prevention of knee injuries,noncontact and nonfoul play injuries,and injuries caused by twisting and turning should be of highest priority in decreasing health care costs.  相似文献   

13.
Abstract

The purpose of this study was to determine which of three intensities of treadmill training produced changes in body composition in rats as evidenced by body weight, percentage of fat and specific gravity. Subjects were 60 male Wistar rats 25 to 30 days old when obtained. They were randomly assigned to one of five groups: sedentary controls, spontaneously active controls, and three groups of rats forced to exercise on a treadmill at intensities of 75, 125 and 175 fpm. Forced exercise was applied three times a week for 8 weeks, after which measures of body weight, specific gravity, and percentage of body fat were obtained. Results indicated that the sedentary controls had significantly higher mean body weights than did those which exercised. Rats forced to exercise at 75 fpm had significantly lower specific gravity measures than rats trained at 125 fpm. Sedentary controls had lower specific gravity values than did all rats allowed to exercise. Intensity of treadmill training had no effect on percentage of body fat as determined chemically. However, exercise was effective in reduction of body fat.  相似文献   

14.
Abstract

This study assessed the stability of student/teacher interactional behavior over one academic year. The design of this study was a single-subject, time-series analysis. The studied teacher had 14 years' experience and taught physical education in grades K–6. Data were collected using the Cheffers Adaptation of Flanders Interaction Analysis System (CAFIAS) (Cheffers, Mancini, & Martinek, 1980). A total of 52 classes were observed at equally spaced time intervals. Data were subjected to univariate Box-Jenkins time-series analyses to determine stationarity. Autocorrelation functions indicated only 5 of the 20 CAFIAS categories demonstrated significant (p <.01) stationarity. These five variables combined accounted for 28.5% of the total student/teacher interactional behavior. Finding less than 30% of behavior stable over a year's time led to the conclusion that the teaching behavior observed may lack the stability necessary for making the inferential generalizations common to natural science research.  相似文献   

15.
Abstract

The effect of actively warming the forearm musculature on dynamic grip endurance was investigated by comparing the performance of the left and right hands, with or without warming-up, on a spring-loaded grip ergometer. There were 21 male subjects, aged 19 to 23. Warming-up consisted of 9 min. of four hand and wrist exercises conducted in 30-sec. bouts, at a rate of one repetition per sec., with 15-sec. intervals between bouts. This warm-up was shown to lead to temperature increases of between 1.6 C and 2.6 C in the flexor digitorum sublimis muscles of five subjects. Warming-up had no effect on grip endurance.  相似文献   

16.
Abstract

The purpose of this study was to examine the development of skill competence and tactical sophistication during a games unit conducted following the features of sport education provided by Siedentop (1994). One team of six players was followed through a 30-lesson season of “Ultimate.” Using Gréhaigne, Godbout, and Bouthier's (1997) formula for an efficiency index, together with a number of other measures of skill and tactical competence, it was determined that these students made significant improvements in selection and execution dimensions of the game. Furthermore, lower skilled students did not feel marginalized within their teams and believed they had equal opportunities for improvement. The key reasons for developing competence in this setting were the sufficient length of the season to allow for significant practice opportunities and the consistent team membership throughout season, which allowed all players to develop a sense of usefulness. This curriculum model provides one way students can develop skills through a system of game playing, provided sport education units are structured to prevent the more skillful players from dominating the games.  相似文献   

17.
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18.
Objective: To examine children’s energy expenditure (EE) during object projection skill performance at three intensity intervals. Methods: Children’s (42, Mage = 8.1) average metabolic equivalents of task (METs) were calculated using a COSMED K4b2 while they repeatedly performed blocks of kicking, throwing (overhand), and striking (two-handed) during 6, 12, and 30-s interval conditions. A repeated-measures analysis of covariance examined differences in METs while controlling for skill level. Results: Data indicated a main effect for interval condition (df = 2, 123, F = 94.36, p <.001, η2 = .605). Post hoc t-tests demonstrated decreasing performance interval times yielded progressively higher METs (p <.001) across the three conditions (30s = 4.5±0.8 METs, 12s = 6.3±1.3, 6s = 8.3±1.6). There also was a main effect for sex (df = 1,120, F = 52.28, p <.001 η2 = .305). Boys demonstrated higher METs at each performance interval (p <.001). Conclusion: Skill practice with a maximum of one trial every 30s resulted in the equivalent of at least moderate physical activity (>4.0 METs) and intervals of 6s demonstrated vigorous physical activity (>7.0 METs). Practicing/performing object projection skills, even at intervals that allow for adequate instruction and feedback (i.e., 1 trial/30s), promotes MVPA in children.  相似文献   

19.
Purpose: We sought to compare the effects of physical practice (PP) and mental practice (MP) on the immediate and long-term learning of the finger-to-thumb opposition sequence task (FOS) in children; in addition, we investigated the transfer of this learning to an untrained sequence of movements and to the contralateral untrained hand. Method: This study included thirty-six 9- and 10-year-old children who were randomly allocated into 3 groups: MP, PP, and no practice (NP). The MP and PP groups were subjected to a single session of training with the dominant trained hand. MP participants were trained by mentally rehearsing the movements, PP participants were trained by executing the movements, and the NP group had no training. The performance of the trained sequence (TS) and untrained reverse sequence (URS) by each of the 3 groups was evaluated under identical conditions before training, after 5 min, and at 4 days, 7 days, and 28 days after training. Results: Whereas both trained groups (MP and PP) showed statistically significant improvement in TS using the trained hand at all assessment points after the training, only MP participants were able to transfer the performance gains from the TS to the URS and from the trained hand to the untrained opposite hand. Conclusion: Children were able to learn the FOS through MP or PP with a similar level of performance. Unlike PP, MP allowed for the transfer of performance gain to the URS and to the opposite hand, suggesting that the internal representations developed by MP were effector-independent.  相似文献   

20.
Abstract

The purpose of this study was to determine if children, ages 6 to 14, would experience greater internal locus of control as a result of participation in an eight-week sports fitness summer camp program. Locus of control is the belief in one's own capacity to control reinforcements. An internally controlled person perceives himself as being in control of what happens, while an externally controlled individual feels that luck, fate, chance, or powerful forces too complex to understand determine what happens to him. Subjects were 74 boys and 35 girls enrolled in the Emory University Sports Fitness Camp in the summer of 1975. During the first week of the camp, the Children's Nowicki-Strickland Internal-External Control Scale (CNS-IE) and a battery of physical fitness tests were administered to the campers. The procedure was repeated at the conclusion of the eight-week program. Results indicated that there were significant changes from an external to an internal locus of control as well as significant improvement in the six measures of physical fitness. It was concluded that the camp experience was accompanied by a stronger belief, on the part of the children, in their own ability to control what happens  相似文献   

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