Effect of post-match cold-water immersion on subsequent match running performance in junior soccer players during tournament play   总被引：2，自引：1，他引：1  

Rowsell GJ  Coutts AJ  Reaburn P  Hill-Haas S 《Journal of sports sciences》2011,29(1):1-6

In this study, we investigated the effects of two hydrotherapy interventions on match running performance and perceptual measures of fatigue and recovery during a 4-day soccer tournament. Twenty male junior soccer players were assigned to one of two treatment groups and undertook either cold-water immersion (5 × 1 min at 10 °C) or thermoneutral water immersion (5 × 1 min at 34 °C) after each match. High-intensity running distance (>15 km · h?1) and total distance covered, time spent in low (<80% maximum heart rate), moderate (80-90% maximum heart rate), and high (>90% maximum heart rate) heart rate zones, and rating of perceived exertion (RPE) were recorded for each match. Perceptions of general fatigue and leg soreness were recorded approximately 22 h after each match. There were decreases in both groups across the 4-day tournament for high-intensity running distance (P = 0.006, Cohen's d = 0.63), total distance run (P < 0.001, d = 0.90), time in high heart rate zone (P = 0.003, d = 0.90), and match RPE (P = 0.012, d = 0.52). Cold-water immersion was more effective than thermoneutral immersion for reducing the perception of leg soreness (P = 0.004, d = -0.92) and general fatigue (P = 0.007, d = -0.91), ameliorating the decrement in total distance run (P = 0.001, d = 0.55), and maintaining time in the moderate heart rate zone (P = 0.01, d = 1.06). In conclusion, cold-water immersion mediates the perceptions of fatigue and recovery and enhances the restoration of some match-related performance measures during a 4-day tournament.  相似文献   

VO2 prediction and cardiorespiratory responses during underwater treadmill exercise     

Greene NP  Greene ES  Carbuhn AF  Green JS  Crouse SF 《Research quarterly for exercise and sport》2011,82(2):264-273

We compared cardiorespiratory responses to exercise on an underwater treadmill (UTM) and land treadmill (LTM) and derived an equation to estimate oxygen consumption (VO2) during UTM exercise. Fifty-five men and women completed one LTM and five UTM exercise sessions on separate days. The UTM sessions consisted of chest-deep immersion, with 0, 25, 50, 75, and 100% water-jet resistance. All session treadmill velocities increased every 3 min from 53.6 to 187.8 m x min(-1). Cardiorespiratory responses were similar between LTM and UTM when jet resistance for UTM was 50%. Using multiple regression analysis, weight-relative VO2 could be estimated as: VO2 (mLO2 c kg(-1) x min(-1)) = 0.19248 x height (cm) + 0.17422 x jet resistance (% max) + 0.14092 x velocity (m x min(-1)) -0.12794 x weight (kg)-27.82849, R2 = .82. Our data indicate that similar LTM and UTM cardiorespiratory responses are achievable, and we provide a reasonable estimate of UTM VO2.  相似文献   

Coaching competency and satisfaction with the coach: a multi-level structural equation model     

Myers ND  Beauchamp MR  Chase MA 《Journal of sports sciences》2011,29(4):411-422

The purpose of this initial predictive validity study was to determine the ability of measures derived from the Athletes' Perceptions of Coaching Competency Scale II?-?High School Teams (APCCS II-HST) to predict satisfaction with the head coach. Specification of the statistical model was informed by the mediational model of coach-athlete interactions. The technical quality of the satisfaction measure was evaluated before testing the predictive validity of the coaching competency measures. Data were collected from athletes of seven sports. Athlete observations (N?=?748) were clustered within teams (G?=?74). Multi-group confirmatory factor analyses (CFA) provided evidence for factorial invariance of a reduced version of the satisfaction measure by athlete gender. Multi-level CFA provided evidence of model-data consistency for a reduced version of the satisfaction measure. Multi-level structural equation modelling provided evidence for the ability of latent coaching competency to positively predict latent satisfaction at both the athlete level (technique competency and motivation competency) and the team level (coaching competency) and for close model-data fit. Implications of this study include: that the APCCS II-HST should be viewed as a replacement for the Coaching Competency Scale when the intended population is appropriate; a preliminary multi-level measurement model for satisfaction with one's coach that should be considered as a potential starting point in subsequent studies; and empirical support for a key relationship proposed in the mediational model of coach-athlete interactions.  相似文献   

Expelled from Childcare: Suspension and Expulsion Practices in One State’s Community Childcare Centers     

Giordano  Keri  Vega  Vanessa  Gubi  Aaron 《Early Childhood Education Journal》2022,50(1):135-144

Early Childhood Education Journal - Suspension and expulsion, typically thought of as discipline practices for high school students, occur at the early childhood level. In fact, 3- and 4-year old...  相似文献   

A prospective,randomized crossover study comparing direct inspection by light microscopy versus projected images for teaching of hematopathology to medical students          下载免费PDF全文

Aaron M. Carlson  Ellen D. McPhail  Vilmarie Rodriguez  Georgene Schroeder  Alexandra P. Wolanskyj 《Anatomical sciences education》2014,7(2):130-134

Instruction in hematopathology at Mayo Medical School has evolved from instructor‐guided direct inspection under the light microscope (laboratory method), to photomicrographs of glass slides with classroom projection (projection method). These methods have not been compared directly to date. Forty‐one second‐year medical students participated in this pilot study, a prospective, randomized, crossover study measuring educational performance during a hematology pathophysiology course. The students were randomized to one of two groups. All students received the same didactic lectures in the classroom and subsequent case‐based review of peripheral blood smears using either laboratory or projection methods, on day one with a crossover to the other method on day two. Pre‐ and post‐test examinations centered on morphology recognition measured educational performance on each day, followed by a questionnaire identifying the student's favored method. There was no significant difference in the pre‐test and post‐test scores between the two teaching methods (rank‐sum P = 0.43). Students overwhelmingly preferred the projection method and perceived it as superior (76%), although post‐test scores were not significantly different. Student's recommended method was split with 50% favoring the projection method, 43% favoring a combined approach, and 23% noting logistical challenges to the laboratory. In this study, the laboratory and projection method were equivalent in terms of educational performance for hematopathology among medicals students. A classroom‐based approach such as the projection method is favored, given the large class sizes in undergraduate medical education, as well as the ergonomic challenges and additional resources required for large group instruction in a laboratory setting. Anat Sci Educ 7: 130–134. © 2013 American Association of Anatomists.  相似文献   

Blocking between landmarks during 2-D (touchscreen) and 3-D (ARENA) search tasks with pigeons     

Kenneth J. Leising  Jared Wong  Chad M. Ruprecht  Aaron P. Blaisdell 《Learning & behavior》2014,42(4):357-364

Many studies investigating cue competition have focused on the blocking effect. We investigated the blocking effect with pigeons using a landmark-based spatial search task in both a touchscreen preparation (Exp. 1a) and an automated remote environmental navigation apparatus (Exp. 1b). In Phase 1, two landmarks (LMs: A and Z) appeared on separate trials as colored circles among a row of eight (touchscreen) or six (ARENA) identical response units. Subjects were rewarded for pecking at a target response unit to the right of LM A and to the left of an extraneous LM, Z. During the blocking trials in Phase 2, LM X was presented in compound with a second LM (A) that had been previously trained. On control trials, LM Y was presented in compound with LM B and a target in the same manner as in the trials of AX, except that neither landmark had previously been trained with the target. All subjects were then tested with separate trials of A, X, B, and Y. Testing revealed poor spatial control by X relative to A and Y. We report the first evidence for a spatial-blocking effect in pigeons and additional support for associative effects (e.g., blocking) occurring under similar conditions (e.g., training sessions, spatial relationships, etc.) in 3-D and 2-D search tasks.  相似文献   

Frederick Augustus Genth 1820–1893 chemist—mineralogist—collector     

W.M. Myers  S. Zerfoss 《Journal of The Franklin Institute》1946,241(5):341-354

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Book reviews     

Aaron Wildavsky  Allen R. Salzman 《Minerva》1991,29(2):231-246

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Mixed-method pre-cooling reduces physiological demand without improving performance of medium-fast bowling in the heat     

Minett GM  Duffield R  Kellett A  Portus M 《Journal of sports sciences》2012,30(9):907-915

This study examined physiological and performance effects of pre-cooling on medium-fast bowling in the heat. Ten, medium-fast bowlers completed two randomised trials involving either cooling (mixed-methods) or control (no cooling) interventions before a 6-over bowling spell in 31.9±2.1°C and 63.5±9.3% relative humidity. Measures included bowling performance (ball speed, accuracy and run-up speeds), physical characteristics (global positioning system monitoring and counter-movement jump height), physiological (heart rate, core temperature, skin temperature and sweat loss), biochemical (serum concentrations of damage, stress and inflammation) and perceptual variables (perceived exertion and thermal sensation). Mean ball speed (114.5±7.1 vs. 114.1±7.2 km · h(-1); P = 0.63; d = 0.09), accuracy (43.1±10.6 vs. 44.2±12.5 AU; P = 0.76; d = 0.14) and total run-up speed (19.1±4.1 vs. 19.3±3.8 km · h(-1); P = 0.66; d = 0.06) did not differ between pre-cooling and control respectively; however 20-m sprint speed between overs was 5.9±7.3% greater at Over 4 after pre-cooling (P = 0.03; d = 0.75). Pre-cooling reduced skin temperature after the intervention period (P = 0.006; d = 2.28), core temperature and pre-over heart rates throughout (P = 0.01-0.04; d = 0.96-1.74) and sweat loss by 0.4±0.3 kg (P = 0.01; d = 0.34). Mean rating of perceived exertion and thermal sensation were lower during pre-cooling trials (P = 0.004-0.03; d = 0.77-3.13). Despite no observed improvement in bowling performance, pre-cooling maintained between-over sprint speeds and blunted physiological and perceptual demands to ease the thermoregulatory demands of medium-fast bowling in hot conditions.  相似文献   

The Socialization of Emotion: Learning Emotion Management at the Fire Station     

Clifton Scott  Karen Kroman Myers 《Journal of Applied Communication Research》2005,33(1):67-92

In a variety of fields, particularly human service occupations, the management of emotion is a precondition of employee and client well being. Based on qualitative data from participant observation and interviews, this study examines how firefighters are socialized to manage feelings and emotional displays. It concludes that firefighters recognized a need to manage their own emotions and those of their clients in order to deliver adequate service. Veteran firefighters facilitated the use of emotion labor techniques among newcomers by considering the emotion management knowledge and capabilities of job candidates during employee selection processes, providing habituated emotional events, and reinforcing customer service expectations. Newcomers actively participated in their own socialization to local emotion expectations through observational information seeking, retrospective surveillance, and performance of a normative newcomer role demeanor. The article concludes by offering practical and theoretical implications.  相似文献