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61.
Drawing on an empirical study of IT outsourcing in the UK and Germany, this paper explores the lessons for modularity that can be drawn from the outsourcing of knowledge-intensive business services (KIBS). Because of the inseparability of information and production technologies, IT outsourcing is frequently accompanied by wider transformations in clients’ production technologies. This results in the need for knowledge and organisational coordination in the form of the transfer of staff from the client and the retained IT organisation. Modularity is often presented as a design strategy that stimulates innovation. Our research findings challenge the generalisability of this claim when examining KIBS outsourcing. We show that intangibility of services exacerbates the conflicts between clients and suppliers, which may present obstacles to innovation.  相似文献   
62.
Purpose: The purpose of this study was to determine the influence of eight different small-sided games (SSG) on physical, technical, and decision-making demands of training environments in U14 field hockey. Methods: A total of 13 participants played eight different training games consisting of two 7.5-minute halves, where number of players (three per side or six per side) and/or field characteristics (normal game, cage hockey game, possession game, and two-goals game) was manipulated. Match performance was determined by using notational analysis, and physical demands were determined by using GPS analyses. Results: Findings revealed that lowering the number of players increased the number of technical actions performed per player and the physical demands of the SSG. Findings of the field characteristics manipulation revealed that the possession game forced players to control the ball more as a team, which resulted in more passes (+4.82 passes) and fewer dribbles (?1.48 dribbles) and tackles (?0.69 tackles) compared to the normal game. The two-goals game led to players scoring more goals (+0.61 goals) compared to the normal game, while the cage hockey game increased passing (+1.46 passes) and physical demands (+7.32 meters per minute) compared to the normal game. Conclusion: It can be concluded from these findings that coaches and trainers are able to promote a change in playing behavior, and in turn the development of skills, by manipulating specific constraints of the training environment.  相似文献   
63.
This randomised controlled trial investigated changes in eccentric hamstring strength, 10m sprint speed, and change-of-direction (COD) performance immediately post Nordic hamstring curl (NHC) intervention and following a 3-week detraining period.

Fourteen male team sports athletes were randomised to a do-as-usual control group (CG; = 7) or to a NHC intervention group (NHC; = 7). Isokinetic dynamometry at 180°/s evaluated eccentric hamstring strength immediately post-intervention as the primary outcome measure. Secondary outcomes included 10 m sprint time and COD. Each outcome was measured, pre, immediately post-intervention and following a 3-week detraining period.

Immediately post-intervention significant group differences were observed in the NHC group for eccentric hamstring strength (31.81 Nm?1 vs. 6.44 Nm?1, P = 0.001), COD (?0.12 s vs. 0.20 s; P = 0.003) and sprint (- 0.06 s vs. 0.05 s; P = 0.024) performance. Performance improvements were maintained following a detraining period for COD (?0.11 s vs. 0.20 s; P = 0.014) and sprint (?0.05 s vs. 0.03 s, P = 0.031) but not eccentric hamstring strength (15.67 Nm?1 vs. 6.44 Nm?1, P = 0.145) These findings have important implications for training programmes designed to reduce hamstring injury incidence, whilst enhancing physical qualities critical to sport.  相似文献   

64.
The aims of this study were to compare the physiological and anthropometric characteristics of successful mountain bikers and professional road cyclists and to re-examine the power-to-weight characteristics of internationally competitive mountain bikers. Internationally competitive cyclists (seven mountain bikers and seven road cyclists) completed the following tests: anthropometric measurements, an incremental cycle ergometer test and a 30 min laboratory time-trial. The mountain bikers were lighter (65.3 - 6.5 vs 74.7 - 3.8 kg, P = 0.01; mean - s ) and leaner than the road cyclists (sum of seven skinfolds: 33.9 - 5.7 vs 44.5 - 10.8 mm, P = 0.04). The mountain bikers produced higher power outputs relative to body mass at maximal exercise (6.3 - 0.5 vs 5.8 - 0.3 W·kg -1 , P = 0.03), at the lactate threshold (5.2 - 0.6 vs 4.7 - 0.3 W·kg -1 , P = 0.048) and during the 30 min time-trial (5.5 - 0.5 vs 4.9 - 0.3 W·kg -1 , P = 0.02). Similarly, peak oxygen uptake relative to body mass was higher in the mountain bikers (78.3 - 4.4 vs 73.0 - 3.4 ml·kg -1 ·min -1 , P = 0.03). The results indicate that high power-to-weight characteristics are important for success in mountain biking. The mountain bikers possessed similar anthropometric and physiological characteristics to previously studied road cycling uphill specialists.  相似文献   
65.
Abstract

There is little published data in relation to the effects of caffeine upon cycling performance, speed and power in trained cyclists, especially during cycling of ~60 s duration. To address this, eight trained cyclists performed a 1 km time-trial on an electronically braked cycle ergometer under three conditions: after ingestion of 5 mg · kg?1 caffeine, after ingestion of a placebo, or a control condition. The three time-trials were performed in a randomized order and performance time, mean speed, mean power and peak power were determined. Caffeine ingestion resulted in improved performance time (caffeine vs. placebo vs. control: 71.1 ± 2.0 vs. 73.4 ± 2.3 vs. 73.3 ± 2.7 s; P = 0.02; mean ± s). This change represented a 3.1% (95% confidence interval: 0.7–5.6) improvement compared with the placebo condition. Mean speed was also higher in the caffeine than placebo and control conditions (caffeine vs. placebo vs. control: 50.7 ± 1.4 vs. 49.1 ± 1.5 vs. 49.2 ± 1.7 km · h?1; P = 0.0005). Mean power increased after caffeine ingestion (caffeine vs. placebo vs. control: 523 ± 43 vs. 505 ± 46 vs. 504 ± 38 W; P = 0.007). Peak power also increased from 864 ± 107 W (placebo) and 830 ± 87 W (control) to 940 ± 83 W after caffeine ingestion (P = 0.027). These results provide support for previous research that found improved performance after caffeine ingestion during short-duration high-intensity exercise. The magnitude of the improvements observed in our study could be due to our use of sport-specific ergometry, a tablet form and trained participants.  相似文献   
66.
Abstract

Quiet eye (QE) is a robust phenomenon in golf putting and expert players frequently demonstrate longer QE periods (i.e., the final fixation prior to the onset of the putting motion) relative to their less-skilled counterparts. In this experiment we used a pre-test/post-test design to determine whether we could use novel training aids and instructions to elicit acute changes in QE behaviour after a brief intervention. Three techniques were used: a marker under the ball, a hole-focus instruction, and a novel putting device – the putting box of science (PBoS). We compared gaze behaviour before and after 30 practice putts and found significant changes in QE duration in the absence of concomitant changes in putting performance. The control (?18 ms) and PBoS (+198 ms) groups did not change, the hole-focus group (?287 ms) had a decrease in QE duration, and the marker group (+366 ms) increased in QE duration. These finding are discussed relative to current QE training programs and the implications for development of evidence-based training aids with coach consultation.  相似文献   
67.
ABSTRACT

Modified sports, whereby equipment and rules are manipulated to facilitate skill performance, have been shown to promote skill learning and potentially increase participation. However, it is currently unexplored how key stakeholders – coaches and key figures working in National associations – who are critical stakeholders in implementing and delivering sport programmes, perceive modified sport. This study explored how tennis coaches and key figures working within tennis National associations perceived the impact of implementing a modified tennis campaign on participation and skill development in children and adults. Key figures and coaches around the world completed an online questionnaire. Both groups considered that modified tennis was positively associated with increasing and sustaining participation, skill learning, talent development and people’s attitude towards tennis. Furthermore, participants thought that a rule change (i.e., use of a low-compression ball in children competitions) and the campaign’s core messages (i.e., “serve, rally, score” and “easy, fun, and healthy”) have been critical for the success of the campaign. These results support previous research on the positive impact of modified tennis on skill development and provide a further impetus on implementing modified sports to increase participation. Other sports can adopt similar strategies to improve their modified programmes.  相似文献   
68.
We assessed the effect of physical effort with increasing intensity on neural activity in the visual pathway in volleyball players (n = 10) and non-athletes (n = 10). Participants performed three 10-min tests of increasing intensity on a cycle ergometer. Each participant was assigned individual workloads below the lactate threshold (40% [Vdot]O(2max)), at the lactate threshold (65-75% [Vdot]O(2max)), and above the lactate threshold (80% [Vdot]O(2max)). Four recordings of visual evoked potentials were made: pre-exercise and immediately after each of the three subsequent tests. We assessed neural activity of the visual pathway by examining the amplitude and latency of the N75, P100, and N135 components of the visual evoked potentials waveform. Pre-exercise P100 wave latency was shorter (P < 0.05) in volleyball players than in non-athletes. In non-athletes, the latency of P100 following the first and second effort (40% and 65-75% [Vdot]O(2max)) was reduced compared with pre-exercise (P < 0.01). However, P100 latency increased and P100 amplitude decreased after the third test (80% [Vdot]O(2max)) in non-athletes. In contrast, no significant changes in the latency or amplitude of visual evoked potentials were observed in the athletes in the three tests. Neural conductivity in the visual pathway after exercise might be at least partially dependent on the individual's personal training adaptation status.  相似文献   
69.
Building upon the seminal work of Kosterman and Feshbach (1989), the previous context specific work of Karasawa (2002), and the recent work of Sullivan and Schatz (2009), this paper examines four psychosocial facets of Japanese national identification in relation to a selection of English language learning processes among 401 Japanese university students majoring in English and International Communication. Based upon the literature discussed, a theoretical model of causality was created by the author and tested via the application of a structural equation modeling analysis. The outcome of this process suggests that within the social context of Japan, ‘commitment to national heritage’ is a significant mediator of both ‘nationalistic’ and ‘patriotic’ attitudes. It was also found that ‘nationalism’ was a significant positive predictor of ‘internationalism’ and of a positive ‘orientation toward English speaking culture and community’, whereas ‘patriotism’ was found to be a negative predictor of ‘internationalism’ and of a positive ‘orientation toward English speaking culture and community’. These findings, in addition to other more pedagogically focused outcomes are discussed in relation to the function and promotion of aspects of Japanese national identification, and the possible impact which the various facets, particularly patriotism, may have upon the development of positive intercultural relations and learning English as a foreign language.  相似文献   
70.
Differences in interceptive skill between highly skilled and lesser skilled cricket batsmen were examined using a batting task that required participants to strike front-foot drive strokes from a machine-projected ball to a specified target. Task difficulty was manipulated by varying the width of the bat (normal, half, and third width) and target accuracy, and quality of bat-ball contact was monitored along with temporal and sequential elements of the hitting action. Analyses revealed that the highly skilled batsmen were distinguishable from less skilled counterparts by their higher accuracy under the normal and half-width bat conditions, significantly earlier initiation and completion of the front-foot stride, greater synchronization of the completion of the front-foot stride with the commencement of the downswing of the bat, and consistent timing of downswing relative to ball bounce and impact. In keeping with studies of other hitting sports, temporal and spatial coupling of the downswing to ball bounce to help minimize temporo-spatial error at the point of interception appeared critical to skilled performance. Implications for the understanding of interception and for coaching practice are briefly discussed.  相似文献   
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