The aim of this study was to examine: 1) whether sport supplement use is related to doping and 2) whether sport supplement beliefs mediated this relationship. In Study 1, athletes (N = 598), completed measures of sport supplement use, sport supplement beliefs, and doping attitudes. In Study 2, athletes (N = 475) completed measures of sport supplement use, sport supplement beliefs, and doping likelihood. In both studies, sport supplement use predicted doping outcomes indirectly via sport supplement beliefs. Our findings provide novel evidence to suggest that sport supplement users, who strongly believe that sport supplements are effective, are more likely to dope. For anti-doping organisations wishing to prevent doping, targeting an athlete’s beliefs about sport supplements may improve the effectiveness of anti-doping prevention programmes. 相似文献
Social identity – identity formed through membership in groups – may play an important role in regulating intrateam moral behaviour in youth sport (Bruner, M. W., Boardley, I., & Côté, J. (2014). Social identity and prosocial and antisocial behavior in youth sport. Psychology of Sport and Exercise, 15(1), 56–64. doi:10.1016/j.psychsport.2013.09.003). The aim of this study was to qualitatively examine this potential role through stimulated recall interviews with competitive youth-ice-hockey players. Twenty-three players (Mage = 13.27 years, SD = 1.79) who reported engaging in high, median or low frequency of antisocial teammate behaviour (determined through pre-screening with the Prosocial and Antisocial Behaviour in Sport Scale [Kavussanu, M., & Boardley, I. D. (2009). The prosocial and antisocial behavior in sport scale. Journal of Sport and Exercise Psychology, 31(1), 97–117. doi:10.1123/jsep.31.1.97]) were recruited from eight youth-ice-hockey teams in Canada. Interviews involved participants recalling their thoughts during prosocial/antisocial interactions with teammates, prompted by previously recorded video sequences of such incidents. Thematic analysis of interview data revealed all athletes – regardless of reported frequency of intrateam antisocial behaviour – felt prosocial interactions with teammates enhanced social identity. In contrast, the perceived influence of antisocial teammate behaviour on social identity differed depending on athletes’ reported frequency of intrateam antisocial behaviour; those reporting low and median frequencies described how such behaviour undermines social identity, whereas athletes reporting high frequency did not perceive this effect. The study findings highlight the potential importance of intrateam moral behaviour and social identity for youth-sport team functioning. 相似文献
This study characterises the relationship between gait variability and speed in runners using data from trunk accelerations in each axis.
Twelve participants of varying fitness ran on the treadmill with three sessions of six randomly ordered self-selected speeds. A VO2max test was conducted on the fourth session. Running gait was tracked with inertial sensors. The occurrence of a mid-range speed was analysed for the anterior–posterior, vertical and lateral directional coefficient of variation (CV) of root mean square (RMS) acceleration data.
One participant with noisy gait signals was omitted. The results show all remaining participants consistently showed significant quadratic U-shaped relationships between vertical RMS CV acceleration and speed. Neither anterior–posterior nor lateral RMS CV acceleration were clearly related to speed. These least variable gait speeds were similar to estimates of optimal speed derived from minimum cost of transport with speed.
In conclusion, there exists a mid-range speed for each runner with the least variable gait in the vertical direction, and this occurred significantly more often than would be expected by chance (P < 0.05). However, there are no prominent patterns for the anterior–posterior and lateral directions. This finding supports anecdotal evidence from runners and coaches concerning gait consistency. 相似文献
Background: Coaches are central to the development of the expert performer and similarly to continued lifelong participation in sport. Coaches are uniquely positioned to deliver specific technical and tactical instruction and mentoring programmes that support the psychological and social development of athletes in a challenging, goal-oriented and motivational environment. The current study aimed to qualitatively investigate current coach learning sources and coaches’ educational backgrounds in team sports in Ireland. Methods: Coaches from five team sports in Ireland were asked to complete an online questionnaire. Subsequently male coaches (n?=?19) from five team sports who completed the questionnaire and met the inclusion criteria were invited to attend a follow-up semi-structured interview. Inclusion criteria for coaches were that they possess at least 10 years’ experience coaching their sport and were coaching more than 4 hours per week. Results/Discussion: Formal coach education does not meet the needs of high performance coaches who rely more on self-directed learning and coaching experience as their main sources of CPD. Although prior playing experience at a high level is both valuable and desirable, there are concerns about fast-tracking of ex-players into high performance coaching roles. Conclusions: Preferred sources of education and the best learning environment for coaches of team sports in Ireland are more informal than formal. Further research is needed to examine how this learning is applied in a practical manner by examining coaching behaviours and the impact it has on the athlete development process. 相似文献
During the competitive season, soccer players are likely exposed to numerous factors that may disrupt the process of sleep. The current investigation looked to evaluate a practical sleep hygiene strategy (10-min showering at ~40°C before lights out), within a group of 11 youth soccer players in comparison to normal sleeping conditions (control). Each condition consisted of three days within a randomised crossover trial design. Sleep information was collected using a commercial wireless bedside sleep monitor. Measures of skin temperature were evaluated using iButton skin thermistors to establish both distal and proximal skin temperatures and distal to proximal gradient. The shower intervention elevated distal skin temperature by 1.1°C (95% CI: 0.1–2.1°C, p?=?.04) on average prior to lights out. The elevation in distal temperature was also present during the first 30-min following lights out (1.0°C, 95% CI: 0.4–1.6°C, p?<?.01). The distal to proximal gradient also showed a significant effect between the conditions within the first 30-min after lights out (0.7°C, 95% CI: 0.3–1.2°C, p?<?.01). On average the sleep latency of the youth soccer players was ?7-min lower (95% CI: ?13 to ?2?min, p?<?.01) and sleep efficiency +2% higher (95% CI: 1–3%; p?<?.01) in the shower condition. These findings demonstrate that a warm shower performed before lights out may offer a practical strategy to promote thermoregulatory changes that may advance sleep onset latency and improve sleep efficiency in athletes. 相似文献
The concept of the transfer of kinetic energy (KE) sequentially through the human body from proximal to distal segments is
an influential concept in biomechanics literature. The present study develops this area of research through investigation
of segmental sequencing of the transfer of KE by means of computer simulation. Using a musculoskeletal computer model previously
developed by the authors, driven using three-dimensional kinematic data from a single elite male golfer, combined inverse
and forward dynamics analyses enabled derivation of KE. Rigid body segments of torso, hips, arms and clubhead were examined
in line with previous literature. Using this method a driver swing was compared to a 7 iron swing. Findings showed a high
level of correlation between driver and iron peak KE and timing of peak KE relative to impact. This seems to indicate equivalent
trunk and arms linear velocity, thus force applied, for an iron shot and a driver shot. There were highly significant differences
between KE output for body segments for both clubs. In addition, peak KE magnitudes increased sequentially from proximal to
distal segments during swing simulations for both the driver and 7 iron. This supports the principle of the summation of speed.
However, timing of peak KE was not sequential from proximal to distal segments, nor did segments peak simultaneously. Rather,
arms peaked first, followed by hips, torso and club. This seems to indicate a subjective optimal coordination of sequencing.
Currently, it is not possible to prescribe isometric exercise at an intensity that corresponds to given heart rates or systolic blood pressures. This might be useful in optimizing the effects of isometric exercise training. Therefore, the aim of this study was to explore the relationships between isometric exercise intensity and both heart rate and systolic blood pressure during repeated incremental isometric exercise tests. Fifteen participants performed seated isometric double-leg knee extension, during which maximum voluntary contraction (MVC) was assessed, using an isokinetic dynamometer. From this, a corresponding peak electromyographic activity (EMG(peak)) was determined. Subsequently, participants performed two incremental isometric exercise tests (at least 48 h apart) at 10, 15, 20, 25, and 30% EMG(peak), during which steady-state heart rate and systolic blood pressure were recorded. In all participants, there were linear relationships between %EMG(peak) and heart rate (r at least 0.91; P < 0.05) and between %EMG(peak) and systolic blood pressure (r at least 0.92; P < 0.05). Also, when repeated tests were compared, there were no differences in the slopes (P > 0.50) or elevations (P > 0.10) for either of the relationships. Therefore, these linear relationships could be used to identify isometric exercise training intensities that correspond to precise heart rates or systolic blood pressures. Training performed in this way might provide greater insight into the underlying mechanisms for the cardiovascular adaptations that are known to occur as a result. 相似文献
How can the validity of performance assessments be established? What type of logical argumentation is necessary to generalize from a particular assessment to the ability or abilities of interest? 相似文献
Abstract A long walk in the “world” of contemporary art gives multiple views of interlocking ecologies that, in their particularities, contradict the stereotypes suggested by language, invert “north” and “south,” question what is “traditional” in artistic practices, reflect on the intermix of society and art, glimpse the colonial mind in postmodern dress, and illuminate a restless subculture of professional migrants. What does our ramble reveal about the institution of contemporary art? “Diversity” hardly seems an adequate word. 相似文献