Canadian journal of sport sciences = Journal canadien des sciences du sport最新文献

This paper examines the relationship between imagery and the acquisition of motor skills. Since most of the research in the motor domain has considered imagery under the topic of mental practice, a comparison between imagery and mental practice is first drawn. Then the basic mental practice paradigm is outlined and research on the effects of imagery is summarized. Factors influencing the use of imagery are considered, including the task, the imagery instructions, and individual imagery abilities. Implications for employing imagery in the teaching of motor skills are discussed and, finally, an approach to studying imagery and motor skills is put forward.

The purpose of this study was to evaluate the pain alleviating effect of dexamethasone iontophoresis on delayed onset muscle soreness (DOMS) produced via an eccentric exercise bout, and to determine the effect on muscle function. Baseline data were collected on 18 female subjects for maximum isometric knee extension contraction (MVC), knee extension peak torque (PT), knee extension work (W), and muscle soreness perception (SP). All values were subsequently reassessed 24 and 48 hours after a 10-min bout of bench stepping. Immediately following the 24-hr reassessment, the experimental (E) (N = 6) and placebo (P) (N = 6) groups received iontophoresis treatment while the control (C) group (N = 6) received no treatment. Percent deviation from baseline of SP was significantly less at 48 hours (p less than 0.05) for the E group compared to P and C groups. However, MCV, PT, and W were no different between the three groups at 48 hours post muscle soreness bout.

This study investigated the extent to which decisions by coaches and athletic trainers concerning the return of injured athletes to competition were influenced by the player's status and the game situation. Samples were drawn from Oregon high school and Canadian university basketball teams. Coaches and athletic trainers completed a questionnaire in which they decided whether an injured player should be returned to competition. The scenarios included winning, losing, or close games and involved a starter, first substitute, or bench player. Chi-square analyses revealed that coaches made decisions based on both a player's status and the game situation. In contrast, athletic trainers' decisions were not significantly influenced by these variables. Since the role of the coach seemingly makes it difficult to make health related decisions concerning injured players, athletic trainers should be responsible for such decisions.

Few studies have attempted to identify the effects of training on performance measures related to ice hockey. The present study was designed to examine the effects of a 7-week hockey-specific training program on the on- and off-ice test performance scores of 14- and 15-year-old (Bantam) hockey players. Pre- and post-training tests of percent fat (ultrasound), center of gravity location, 40-yard dash, vertical jump, and on-ice tests of top speed, acceleration, and concerning ability were completed on 28 male subjects (16 in a training group, 12 in a control group of summer league participants). The training group showed significant improvements (p less than .01) in percent fat, top speed, acceleration, and cornering test performance whereas only percent fat was significantly improved for the control group. The results suggest that performance on tests related to ice hockey can be improved by training specifically for hockey but that performance is not affected by summer league play alone.

The purpose of this study was to compare the strength of knee extensors and elbow extensors in young and older men under conditions of eccentric loading and concentric contractions. Twelve men ages 23 to 32 years and 12 ages 60 to 75 years were tested at two angular velocities of movement, 90 and 180 degrees.s-1, on a KinCom isokinetic dynamometer. Compared to young men, older men had lower concentric peak torque values for elbow (31%) and knee (32%) extensors (p less than 0.05). The older group showed lower eccentric peak torques on all elbow comparisons (21% lower), and for knee extension at the slower velocity (20%). At the faster velocity, knee extension eccentric peak torque did not differ from that of younger men. Differences between the age groups were significantly less for the eccentric muscle action than for the concentric one. The observation of maintained eccentric strength in older men, particularly at fast velocity, warrants research in defining the mechanism.

A pilot study was conducted to investigate the applicability of the Canadian Aerobic Fitness Test (CAFT) for use in epidemiological studies. Thirty subjects ranging in age from 18 to 65 were evaluated for cardiorespiratory fitness on four separate visits. Protocols used included maximal treadmill testing, maximal step testing, and the CAFT. Results from these evaluations suggested that (a) habituation to the CAFT was negligible; (b) prediction of VO2max from the CAFT in fit subjects remains a problem and further equation development for this group may be necessary; (c) maximal step-test protocols do not result in unequivocal VO2max determinations and may lead to misclassification of fitness level; and (d) although the CAFT correlates highly to treadmill VO2max (r = 0.90), a relatively large standard error may result in as high as a 13% error in estimating VO2max and may lead to problems in classifying fitness in some populations (e.g., older unfit).