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    The effect of complex training on horizontal power production in rugby union players : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science at Massey University

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    The use of strength and power training regimes is common place among elite and recreational athletes. However, the application of such methods as direct determinants of improvement in sporting performance is a controversial and much debated topic because the degree of transfer from the training exercise to the sporting application is unknown. In recent years combining strength and sport specific training methods into one training session (complex training) has been promoted as a method to enhance training transfer. The purpose of this project was to examine the effect of complex training on horizontal power production in rugby players. 9 participants completed two four week phases of training (complex and standard) in a randomized order. Participant performance in 5RM squat, horizontal force and horizontal power was tested prior to and at the end of each training phase. A number of significant improvements were observed following complex training: maximum slope of the horizontal force curve increased by 12.29 ±33.59%, maximum power increased by 15.13 ±7.49%, width of the power curve increased by 28.30 ±18.16%, and maximum velocity during the horizontal power test improved by 20.63 ±14.21%. The improvements were significantly different from the respective standard training measures (p ≤.05). It is concluded that power gains were a product of an enhanced ability to produce force at higher velocities. No significant weight gain or significant improvement in 5RM force production was associated with the improvement in maximum power. Therefore it is inferred that neural mechanisms accounted for the difference following complex training. The results presented here suggest that complex training not only improves horizontal power production but also transfers performance improvements to an untrained task by improving the rate of force development in the horizontal force condition. It appears that the complex training regime has in some way created a persistent change in the control mechanisms regulating the performance of both the horizontal strength and power conditions

    Post-training load-related changes of auditory working memory: An EEG study

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    Working memory (WM) refers to the temporary retention and manipulation of information, and its capacity is highly susceptible to training. Yet, the neural mechanisms that allow for increased performance under demanding conditions are not fully understood. We expected that post-training efficiency in WM performance modulates neural processing during high load tasks. We tested this hypothesis, using electroencephalography (EEG) (N = 39), by comparing source space spectral power of healthy adults performing low and high load auditory WM tasks. Prior to the assessment, participants either underwent a modality-specific auditory WM training, or a modality-irrelevant tactile WM training, or were not trained (active control). After a modality-specific training participants showed higher behavioral performance, compared to the control. EEG data analysis revealed general effects of WM load, across all training groups, in the theta-, alpha-, and beta-frequency bands. With increased load theta-band power increased over frontal, and decreased over parietal areas. Centro-parietal alpha-band power and central beta-band power decreased with load. Interestingly, in the high load condition a tendency toward reduced beta-band power in the right medial temporal lobe was observed in the modality-specific WM training group compared to the modality-irrelevant and active control groups. Our finding that WM processing during the high load condition changed after modality-specific WM training, showing reduced beta-band activity in voice-selective regions, possibly indicates a more efficient maintenance of task-relevant stimuli. The general load effects suggest that WM performance at high load demands involves complementary mechanisms, combining a strengthening of task-relevant and a suppression of task-irrelevant processing

    The Impact of Power Training on Balance and Visual Feedback Removal

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    Because power training has been known to augment stability, the purpose of this study was to assess whether the removal of visual input affects lower limb muscle power production in young women who are resistance trained to the same degree it affects the untrained. This provided insight as far as the need for resistance training protocols in a largely untrained visually impaired population. To study this, fourteen college-aged female participants (18-23 years) performed a seated double-leg press on a leg sled machine, isolating power production of the lower limbs. After establishing baselines, which involved finding an average of power produced during five trials, the subjects were asked to close their eyes for the following set of five pushes. The power production was assessed by utilizing a Tendo Unit, with placement on one of the limbs of the machine, to measure power output during leg extension (measured in Watts). Statistics analyzed in SPSS determined the average power deficit of the athletic population to be 11.57 Watts, whereas the general population had an average power deficit of 37.43 Watts. The deficits experienced by each respective group upon visual removal were significantly different from one another, as evidenced by a p-value of .048. This accentuated the power-trained group’s resilience. A suggested training plan regimen including cardiorespiratory, resistance, flexibility, and neuromotor exercises has been appended for persons experiencing visual impairment and seeking to better their balance through power

    Effects of a Tapering Period on Physical Condition in Soccer Players

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    The aim of this research was to analyze the effects of a 2-week step tapering period on lower-limb muscle power, change of direction (COD) and acceleration capacities, and on the stress-recovery state in an amateur soccer team. Twenty-two male players were included in the study. After a 6-week progressive training, the sample was divided into experimental group (EG) (n = 11), which did a 2-week period of taper in which training volume was 50% reduced (intensity was kept high) and control group (CG) (n = 11), which kept on with the training. Muscle power (countermovement jump test), acceleration (10-m sprint test), COD (Illinois test), and stress and recovery perceptions (RESTQ questionnaire) were evaluated before training, at the end of it (pretapering, PRE-TP) and after the tapering period (posttapering, POST-TP). After the taper, the EG in comparison with the CG showed significantly improved power (1,029.71 ± 108.51 W·kg−1 vs. 1,084.21 ± 110.87 W·kg−1; p ≤ 0.01), acceleration (1.72 ± 0.09 seconds vs. 1.67 ± 0.07 seconds; p ≤ 0.05), and lower stress levels (1.9 ± 0.5 vs. 1.6 ± 0.5; p ≤ 0.01) (PRE-TP vs. POST-TP, respectively). Change of direction did not show significant changes. In conclusion, a 2-week step tapering program was found to be an effective periodization strategy to increase muscle power and acceleration, and to reduce stress perception in soccer amateur players

    Worker heterogeneity, new monopsony, and training

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    A worker's output depends not only on his/her own ability but also on that of colleagues, who can facilitate the performance of tasks that each individual cannot accomplish on his/her own. We show that this common-sense observation generates monopsony power and is sufficient to explain why employers might expend resources on training employees even when the training is of use to other firms. We show that training will take place in better-than-average or ‘good’ firms enjoying greater monopsony power, whereas ‘bad’ firms will have low-ability workers unlikely to receive much training

    Amending the Amendment Procedures of Article V

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    Until the 1950s, Swedish cross-country skiers relied on natural training. But in the wake of failure at the 1952 Winter Olympics, the Swedish Ski Federation initiated a scientification of training. They sought aid from physiologists to “rationalize” the training of elite skiers. But the advocates of natural training resisted this new, scientific model. A battle was fought between the two sides, and a number of different power strategies were used by the federation and the physiologists to promote scientific training. In this article, the battle between different training regimes is analyzed using theories of power and sportification. The article concludes that the shift towards rational training during the period 1948-1972 was part of a larger rationalization of Swedish society. And the relative slowness of implementation was due to a lack of professionalization (of coaches). Rationalization should therefore be seen as one of the later stages of sportification. QC 20150114Rationell träning: Vetenskapliggörandet av träning för längdskidåknin

    Training Optimization for Energy Harvesting Communication Systems

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    Energy harvesting (EH) has recently emerged as an effective way to solve the lifetime challenge of wireless sensor networks, as it can continuously harvest energy from the environment. Unfortunately, it is challenging to guarantee a satisfactory short-term performance in EH communication systems because the harvested energy is sporadic. In this paper, we consider the channel training optimization problem in EH communication systems, i.e., how to obtain accurate channel state information to improve the communication performance. In contrast to conventional communication systems, the optimization of the training power and training period in EH communication systems is a coupled problem, which makes such optimization very challenging. We shall formulate the optimal training design problem for EH communication systems, and propose two solutions that adaptively adjust the training period and power based on either the instantaneous energy profile or the average energy harvesting rate. Numerical and simulation results will show that training optimization is important in EH communication systems. In particular, it will be shown that for short block lengths, training optimization is critical. In contrast, for long block lengths, the optimal training period is not too sensitive to the value of the block length nor to the energy profile. Therefore, a properly selected fixed training period value can be used.Comment: 6 pages, 5 figures, Globecom 201
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