Fluctuations in running and skill-related performance in elite rugby union match-play

This study investigated end-game and transient changes in running activities and whether these were concomitantly associated with reductions in skill-related performance in senior international rugby union match-play. Altogether, 18 official matches were analysed (322 individual observations) using computerised video-based tracking and event coding (Amisco Pro^®, SUP, Nice, France). In forwards and backs, trivial to small reductions (% difference: ?2.1, ±1.3 to ?10.0, ±4.0%) in total distance and that covered at high speeds (>18.0?km?h^?1) occurred in the second- versus the first-half while there were trivial differences in skill-related performance measures (?2.3, ±4.5 to 7.5, ±14.0%). In both positions, small to moderate declines (?42, ±10 to ?21, ±7%) occurred in high-speed running in the final 10-min and 5-min periods versus mean values for all other 10-min and 5-min periods throughout the game while only small changes (?18, ±51 to 13, ±41%) in skill-related performance were observed. Trivial changes in running and skill-related performance (?11, ±74 to 7, ±39%) were observed in the 5-min period immediately following the most intense 5-minute periods of play compared to mean performance over the other 5-min periods. These findings suggest that international rugby union players were generally able to maintain skill-related performance over the course of match-play even when declines in running performance occurred.     

Ethnicity as a moderator of the theory of planned behavior and physical activity in college students

Most college students do not meet physical activity (PA) guidelines, and ethnic disparities exist. The present study examined the utility of the theory of planned behavior (TPB) in explaining PA intentions and behavior in black and white college students and whether any TPB relationships were moderated by ethnicity. Black (n=170) and white (n=180) students completed a baseline TPB questionnaire and PA assessment 2 weeks later Hierarchical latent variable regression analyses showed that affective attitude, subjective norm, and perceived behavioral control (PBC) were significant predictors of intention for both ethnic groups, whereas the PBC-intention relationship was significantly stronger for white students. Intention significantly predicted PA for both ethnic groups. Furthermore, common and ethnic-specific beliefs were identified.     

在训练过程中发展心理技能:强化教练的作用

教练员、父母、管理者和运动员都很感兴趣的一个话题是:在最高水平的运动竞赛中,与身体状态和技术、战术技能相比,心理技能是如何的重要.     

In-school and out-of-school physical activity in primary and secondary school children

The aim of this study was to compare in-school and out-of-school physical activity within a representative sample. Socio-demographic, physical activity, and anthropometric data were collected from a random sample of children (250 boys, 253 girls) aged 3-16 years attending nine primary and two secondary schools. Actigraph GT1M accelerometers, worn for seven days, were used to estimate physical activity levels for in-school (typically 09.00-15.00 h), out-of-school (weekday), and weekend periods. Physical activity as accelerometer counts per minute were lower in school versus out of school overall (in school: 437.2 +/- 172.9; out of school: 575.5 +/- 202.8; P < 0.001), especially in secondary school pupils (secondary: 321.6 +/- 127.5; primary: 579.2 +/- 216.3; P < 0.001). Minutes of moderate-to-vigorous physical activity accumulated in school accounted for 29.4 +/- 9.8% of total weekly moderate-to-vigorous physical activity overall but varied by sector (preschool: 37.4 +/- 6.2%; primary: 33.6 +/- 8.1%; secondary: 23.0 +/- 9.3%; F = 114.3, P < 0.001). Approximately half of the children with the lowest in-school activity compensated out of school during the week (47.4%) and about one-third at the weekend (30.0%). Overall, physical activity during the school day appears to be lower than that out of school, especially in secondary school children, who accumulate a lower proportion of their total weekly moderate-to-vigorous physical activity at school than younger children. As low in-school activity was compensated for beyond the school setting by less than half of children, promoting physical activity within the school day is important, especially in secondary schools.     

Psychosocial correlates of cardiorespiratory fitness and muscle strength in overweight and obese post-menopausal women: a MONET study

The purpose of this study was to examine the psychosocial correlates of cardiorespiratory fitness (VO2peak) and muscle strength in overweight and obese sedentary post-menopausal women. The study population consisted of 137 non-diabetic, sedentary overweight and obese post-menopausal women (mean age 57.7 years, s = 4.8; body mass index 32.4 kg.m(-2), s = 4.6). At baseline we measured: (1) body composition using dual-energy X-ray absorptiometry; (2) visceral fat using computed tomography; (3) insulin sensitivity using the hyperinsulinaemic-euglycaemic clamp; (4) cardiorespiratory fitness; (5) muscle strength using the leg press exercise; and (6) psychosocial profile (quality of life, perceived stress, self-esteem, body-esteem, and perceived risk for developing chronic diseases) using validated questionnaires. Both VO2peak and muscle strength were significantly correlated with quality of life (r = 0.29, P < 0.01 and r = 0.30, P < 0.01, respectively), and quality of life subscales for: physical functioning (r = 0.28, P < 0.01 and r = 0.22, P < 0.05, respectively), pain (r = 0.18, P < 0.05 and r = 0.23, P < 0.05, respectively), role functioning (r = 0.20, P < 0.05 and r = 0.24, P < 0.05, respectively), and perceived risks (r = -0.24, P < 0.01 and r = -0.30, P < 0.01, respectively). In addition, VO2peak was significantly associated with positive health perceptions, greater body esteem, and less time watching television/video. Stepwise regression analysis showed that quality of life for health perceptions and for role functioning were independent predictors of VO2peak and muscle strength, respectively. In conclusion, higher VO2peak and muscle strength are associated with a favourable psychosocial profile, and the psychosocial correlates of VO2peak were different from those of muscle strength. Furthermore, psychosocial factors could be predictors of VO2peak and muscle strength in our cohort of overweight and obese sedentary post-menopausal women.     

The behavioral regulation in sport questionnaire (BRSQ): instrument development and initial validity evidence

The purpose of the four studies described in this article was to develop and test a new measure of competitive sport participants' intrinsic motivation, extrinsic motivation, and amotivation (self-determination theory; Deci & Ryan, 1985). The items for the new measure, named the Behavioral Regulation in Sport Questionnaire (BRSQ), were constructed using interviews, expert review, and pilot testing. Analyses supported the internal consistency, test-retest reliability, and factorial validity of the BRSQ scores. Nomological validity evidence was also supportive, as BRSQ subscale scores were correlated in the expected pattern with scores derived from measures of motivational consequences. When directly compared with scores derived from the Sport Motivation Scale (SMS; Pelletier, Fortier, Vallerand, Tuson, & Blais, 1995) and a revised version of that questionnaire (SMS-6; Mallett, Kawabata, Newcombe, Otero-Forero, & Jackson, 2007), BRSQ scores demonstrated equal or superior reliability and factorial validity as well as better nomological validity.     

Most ankle sprain research is either false or clinically unimportant: A 30-year audit of randomized controlled trials

BackgroundLateral ankle sprain is the most common musculoskeletal injury. Although clinical research in this field is growing, there is a broader concern that clinical trial outcomes are often false and fail to translate into patient benefits.MethodsWe audited 30 years of experimental research related to lateral ankle sprain management (n = 74 randomized controlled trials) to determine if reports of treatment effectiveness could be validated beyond statistical certainty.ResultsA total of 77% of trials reported positive treatment effects, but there was a high risk of false discovery. Most trials were unregistered and relied solely on statistical significance, or lack of statistical significance, rather than on interpreting key measures of minimum clinical importance (e.g., minimal detectable change, minimal clinically important difference).ConclusionFuture clinical trials must adopt higher standards of reporting and data interpretation. This includes consideration of the ethical responsibility to preregister their research and interpretation of clinical outcomes beyond statistical significance.     

Academic performance and self-regulatory skills in elite youth soccer players

Although elite athletes have been reported to be high academic achievers, many elite soccer players struggle with a stereotype of being low academic achievers. The purpose of this study was to compare the academic level (pre-university or pre-vocational) and self-regulatory skills (planning, self-monitoring, evaluation, reflection, effort, and self-efficacy) of elite youth soccer players aged 12-16 years (n = 128) with those of 164 age-matched controls (typical students). The results demonstrate that the elite youth soccer players are more often enrolled in the pre-university academic system, which means that they are high academic achievers, compared with the typical student. The elite players also report an increased use of self-regulatory skills, in particular self-monitoring, evaluation, reflection, and effort. In addition, control students in the pre-university system had more highly developed self-regulatory skills than those in the pre-vocational system, whereas no difference was observed within the soccer population. This suggests that the relatively stronger self-regulatory skills reported by the elite youth soccer players may be essential for performance at the highest levels of sport competition and in academia.     

Modifying landing mat material properties may decrease peak contact forces but increase forefoot forces in gymnastics landings

This study investigated how changes in the material properties of a landing mat could minimise ground reaction forces (GRF) and internal loading on a gymnast during landing. A multi-layer model of a gymnastics competition landing mat and a subject-specific seven-link wobbling mass model of a gymnast were developed to address this aim. Landing mat properties (stiffness and damping) were optimised using a Simplex algorithm to minimise GRF and internal loading. The optimisation of the landing mat parameters was characterised by minimal changes to the mat's stiffness (<0.5%) but increased damping (272%) compared to the competition landing mat. Changes to the landing mat resulted in reduced peak vertical and horizontal GRF and reduced bone bending moments in the shank and thigh compared to a matching simulation. Peak bone bending moments within the thigh and shank were reduced by 6% from 321.5 Nm to 302.5Nm and GRF by 12% from 8626 N to 7552 N when compared to a matching simulation. The reduction in these forces may help to reduce the risk of bone fracture injury associated with a single landing and reduce the risk of a chronic injury such as a stress fracture.     

Rating the Quality of Trials in Systematic Reviews of Physical Therapy Interventions

Physical therapists seeking to use evidence to guide their practice may have limited time to read research reports. One way to reduce the time required to identify and read about the research that is relevant to a particular clinical question is to read a systematic review that summarizes multiple studies. This paper explains the process that is used to conduct systematic reviews, which includes the establishment of a protocol, comprehensive searching, appraisal of the quality of the included studies, data extraction and metaanalysis, and consideration of the clinical and research implications of the findings. We also consider how the reader of a systematic review can determine whether the review is likely to provide an unbiased (believable) estimate of the treatment effect. A systematic review of randomized trials of a cardiopulmonary physical therapy intervention is used as an example. The issue of appraisal of quality is then discussed further, with a demonstration of how one validated tool for quality appraisal–the PEDro scale–can be used to evaluate a randomized trial in cardiopulmonary physical therapy.Key Words: systematic review, physical therapy