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1.
This review discusses the leading hypotheses concerning ventilatory control during submaximal exercise. The ventilatory response at the onset of submaximal exercise has been studied extensively. It is generally agreed that expired ventilation (VE) increases rapidly at the initiation of exercise followed by a slower increase in VE until a steady state is reached. In general, there are four schools of thought concerning the mechanisms that are responsible for the exercise hyperpnoea. Two of the hypotheses relate the increase in VE to neural regulation. One group argues that the increase in VE during work is primarily due to afferent neural feedback to the ventilatory control centre while the other group proposes that efferent neural activity can explain the hyperpnoea. A third group of hypotheses submit that humoral mechanisms must be actively involved in the increase in VE during exercise. The leading hypothesis in this area is based on experiments that suggest that CO2 return to the lung provides a stimulus for ventilatory control. Finally, the fourth supposition is that the exercise hyperpnoea may be due to both neural and humoral mechanisms. In summary, although there is persuasive evidence that both humoral and neural factors may play a role in mediating the exercise hyperpnoea, the basic question of whether the response is due solely to humoral or neural mechanisms remains unresolved. 相似文献
2.
Normal and pathological ageing are associated with several motor impairments that reduce quality of life and represent a general challenge for public healthcare systems. Consequently, over the past decades, many scientists and physiotherapists dedicated their research to the development and improvement of safe and costless methods to counteract the progressive decline of motor functions with age. The urgency of finding new and easy to implement methods is even more paramount in case of acute pathologies (e.g. stroke or hip surgery). The frailty of older population makes it difficult or even impossible to use traditional physical therapy at an early stage after the occurrence of a pathology. To that purpose, non-physical approaches such as cognitive training (e.g. memory, attention training) and mental techniques (e.g. motor imagery) have grown in popularity for the elderly. Such methods, involving individual and/or group exercises, have shown particular effects on increasing or maintaining cognitive functions, as well as physical performances. Improving the motor function (especially in older age) requires an improvement of motor execution, i.e. the pathway from the brain motor areas to the muscle but also higher cognitive control. The present work reviews different non-physical interventions that can be used as a complementary approach by asymptomatic or frail older adults, and the effects thereof on functional performance. The use of cognitive training or motor imagery protocols is recommended when physical practice is limited or not possible. Finally, insights into the underlying neurophysiological mechanisms are proposed. 相似文献
3.
In this paper, we identify appropriate statistical methods for analysing categorical differences in discrete variables or 'performance indicators' resulting from performance analysis. The random mechanisms associated with discrete events do not follow a normal distribution; that is, the normal distribution is a continuous not a discrete probability distribution. We propose appropriate statistical methods based on two key discrete probability distributions, the Poisson and binomial distributions. Two approaches are proposed and compared using examples from notational analysis. The first approach is based on the classic chi-square test of significance (both the goodness-of-fit test and the test of independence). The second approach adopts a more contemporary method based on log-linear and logit models fitted using the statistical software GLIM. Provided relatively simple one-way and two-way comparisons in categorical data are required, both of these approaches result in very similar conclusions. However, as soon as more complex models or higher-order comparisons are required, the approach based on log-linear and logit models is shown to be more effective. Indeed, when investigating those factors and categorical differences associated with binomial or binary response variables, such as the proportion of winners when attempting decisive shots in squash or the proportion of goals scored from all shots in association football, logit models become the only realistic method available. By applying log-linear and logit models to discrete events resulting from notational analysis, greater insight into the underlying mechanisms associated with sport performance can be achieved. 相似文献
4.
Alan M. Nevill Greg Atkinson Mike D. Hughes Stephen-Mark Cooper 《Journal of sports sciences》2013,31(10):829-844
In this paper, we identify appropriate statistical methods for analysing categorical differences in discrete variables or 'performance indicators' resulting from performance analysis. The random mechanisms associated with discrete events do not follow a normal distribution; that is, the normal distribution is a continuous not a discrete probability distribution. We propose appropriate statistical methods based on two key discrete probability distributions, the Poisson and binomial distributions. Two approaches are proposed and compared using examples from notational analysis. The first approach is based on the classic chi-square test of significance (both the goodness-of-fit test and the test of independence). The second approach adopts a more contemporary method based on log-linear and logit models fitted using the statistical software GLIM. Provided relatively simple one-way and two-way comparisons in categorical data are required, both of these approaches result in very similar conclusions. However, as soon as more complex models or higher-order comparisons are required, the approach based on log-linear and logit models is shown to be more effective. Indeed, when investigating those factors and categorical differences associated with binomial or binary response variables, such as the proportion of winners when attempting decisive shots in squash or the proportion of goals scored from all shots in association football, logit models become the only realistic method available. By applying log-linear and logit models to discrete events resulting from notational analysis, greater insight into the underlying mechanisms associated with sport performance can be achieved. 相似文献
5.
Arlene Hellerman Margaret Head Skrinar 《Research quarterly for exercise and sport》2013,84(2):188-190
Abstract The field of movement behavior has been strongly led by a research tradition in which manipulations are performed in order to search for differences in dependent variables. In this article, I argue for an alternative viewpoint, in which experimental manipulations are provided so that invariances in dependent variables can be seen. If, in the face of changes in nearly countless dependent variables, a particular simple or derived value remains constant, strong suggestions are provided about the underlying control of the motor system. This method is illustrated with examples of invariances in motor behavior, the most important of which is the tendency for the temporal events in a movement to expand or contract nearly proportionally with movement time so that relative timing is invariant. A model following from these invariances, and criticisms of it, are discussed. 相似文献
6.
Kamen G 《Research quarterly for exercise and sport》2004,75(1):3-8
During the earliest stages of resistance exercise training, initial muscular strength gains occur too rapidly to be explained solely by muscle-based mechanisms. However; increases in surface-based EMG amplitude as well as motor unit discharge rate provide some insight to the existence of neural mechanisms in the earliest phases of resistance exercise training. Moreover, other phenomena such as the cross transfer of strength following unilateral exercise and neural changes following limb immobilization also support a role for neural control in muscular strength. While studies to date have focused on the phenomenon of neural change, future studies will need to focus on the many motoneuron influences as well as intrinsic motoneuronal properties that may be responsible for these neural adaptations. 相似文献
7.
The aim of this study was to assess the effects of variations in the volume and intensity of resistance training in highly skilled athletes on neural adaptive mechanisms: the maximality and pattern of neural drive. The maximality of muscle activation was measured using a high-resolution sample and hold amplifier to record interpolated twitches. The pattern of neural drive was measured by analysing isometric torque-time curves and electromyographic (EMG) characteristics during the performance of rapid isometric contractions at maximal effort. The volume and intensity of training were varied at 4-weekly intervals to systematically emphasize the development of strength, power and motor performance in 14 highly skilled track and field athletes (e.g. discus, hammer, javelin, shot put and weight). Knee extension strength increased significantly by 15% during steady maximal isometric contractions and by 24% during rapid isometric contractions at maximal effort after the 16-week training programme (P < 0.05). Increases in EMG amplitude and rate of EMG activation indicated that improvements to the pattern of neural drive occurred with sport-specific resistance training (P < 0.05). The maximality and pattern of neural drive did not change in the control group. 相似文献
8.
We provide an overview of some of the outstanding papers published in the Journal over the last 25 years within the discipline of psychology. Altogether, almost 300 papers had been published in the Journal under the psychology banner at the start of its silver anniversary year. The greatest contribution of papers has come from the motor control and learning and sport psychology sub-areas, with papers focusing on exercise psychology being a more recent addition. Prominent research themes that have emerged from each of the different sub-areas are reviewed and some notable omissions highlighted. Finally, some issues for sport and exercise psychologists to consider in coming years are briefly highlighted. 相似文献
9.
在回顾国外研究的基础上,对体育运动领域中行为程序研究进行全面的阐述.行为程序包括动作行为和认知或心理两个方面的内容;行为程序作用理论机制包括图式理论、运动技能学习阶段理论、定势假说和心理演练;主要研究领域包括运动技能学习和运动竞赛领域;影响行为程序效果的变量包括技能水平、性别和行为程序的时间节律.从实践的角度,认为体育教师和教练员应当重视行为程序,应用行为程序来提高学生的技能水平和运动员的运动成绩;从研究的角度,认为国内研究者应加大这一领域的研究. 相似文献
10.
Gary Kamen 《Research quarterly for exercise and sport》2013,84(1):3-8
Abstract During the earliest stages of resistance exercise training, initial muscular strength gains occur too rapidly to be explained solely by muscle-based mechanisms. However, increases in surface-based EMG amplitude as well as motor unit discharge rate provide some insight to the existence of neural mechanisms in the earliest phases of resistance exercise training. Moreover, other phenomena such as the cross transfer of strength following unilateral exercise and neural changes following limb immobilization also support a role for neural control in muscular strength. While studies to date have focused on the phenomenon of neural change, future studies will need to focus on the many motoneuron influences as well as intrinsic motoneuronal properties that may be responsible for these neural adaptations. 相似文献
11.
The aim of this study was to assess the effects of variations in the volume and intensity of resistance training in highly skilled athletes on neural adaptive mechanisms: the maximality and pattern of neural drive. The maximality of muscle activation was measured using a high-resolution sample and hold amplifier to record interpolated twitches. The pattern of neural drive was measured by analysing isometric torque–time curves and electromyographic (EMG) characteristics during the performance of rapid isometric contractions at maximal effort. The volume and intensity of training were varied at 4-weekly intervals to systematically emphasize the development of strength, power and motor performance in 14 highly skilled track and field athletes (e.g. discus, hammer, javelin, shot put and weight). Knee extension strength increased significantly by 15% during steady maximal isometric contractions and by 24% during rapid isometric contractions at maximal effort after the 16-week training programme (P < 0.05). Increases in EMG amplitude and rate of EMG activation indicated that improvements to the pattern of neural drive occurred with sport-specific resistance training (P < 0.05). The maximality and pattern of neural drive did not change in the control group. 相似文献
12.
Sidney Grosprêtre Thomas Jacquet Florent Lebon Charalambos Papaxanthis Alain Martin 《European Journal of Sport Science》2018,18(2):209-218
The neural mechanisms explaining strength increase following mental training by motor imagery (MI) are not clearly understood. While gains are mostly attributed to cortical reorganization, the sub-cortical adaptations have never been investigated. The present study investigated the effects of MI training on muscle force capacity and the related spinal and supraspinal mechanisms. Eighteen young healthy participants (mean age: 22.5?±?2.6) took part in the experiment. They were distributed into two groups: a control group (n?=?9) and an MI training group (n?=?9). The MI group performed seven consecutive sessions (one per day) of imagined maximal isometric plantar flexion (4 blocks of 25 trials per session). The control group did not engage in any physical or mental training. Both groups were tested for the isometric maximal plantar flexion torque (MVC) and the rate of torque development (RTD) before and after the training session. In addition, soleus and medial gastrocnemius spinal and supraspinal adaptations were assessed through the recording of H-reflexes and V-waves, with electrical stimulations of the posterior tibial nerve evoked at rest and during MVC, respectively. After one week, only the MI training group increased both plantar flexion MVC and RTD. The enhancement of muscle torque capacity was accompanied by significant increase of electromyographic activity and V-wave during MVC and of H-reflex at rest. The increased cortical descending neural drive and the excitability of spinal networks at rest could explain the greater RTD and MVC after one week of MI training. 相似文献
13.
The aims of this study were to investigate the energy build-up and dissipation mechanisms associated with using an arm swing in submaximal and maximal vertical jumping and to establish the energy benefit of this arm swing. Twenty adult males were asked to perform a series of submaximal and maximal vertical jumps while using an arm swing. Force, motion and electromyographic data were recorded during each performance and used to compute a range of kinematic and kinetic variables, including ankle, knee, hip, shoulder and elbow joint powers and work done. It was found that the energy benefit of using an arm swing appears to be closely related to the maximum kinetic energy of the arms during their downswing, and increases as jump height increases. As jump height increases, energy in the arms is built up by a greater range of motion at the shoulder and greater effort of the shoulder and elbow muscles but, as jump height approaches maximum, these sources are supplemented by energy supplied by the trunk due to its earlier extension in the movement. The kinetic energy developed by the arms is used to increase their potential energy at take-off but also to store and return energy from the lower limbs and to "pull" on the rest of the body. These latter two mechanisms become more important as jump height increases with the pull being the more important of the two. We conclude that an arm swing contributes to jump performance in submaximal as well as maximal jumping but the energy generation and dissipation sources change as performance approaches maximum. 相似文献
14.
Abstract The aims of this study were to investigate the energy build-up and dissipation mechanisms associated with using an arm swing in submaximal and maximal vertical jumping and to establish the energy benefit of this arm swing. Twenty adult males were asked to perform a series of submaximal and maximal vertical jumps while using an arm swing. Force, motion and electromyographic data were recorded during each performance and used to compute a range of kinematic and kinetic variables, including ankle, knee, hip, shoulder and elbow joint powers and work done. It was found that the energy benefit of using an arm swing appears to be closely related to the maximum kinetic energy of the arms during their downswing, and increases as jump height increases. As jump height increases, energy in the arms is built up by a greater range of motion at the shoulder and greater effort of the shoulder and elbow muscles but, as jump height approaches maximum, these sources are supplemented by energy supplied by the trunk due to its earlier extension in the movement. The kinetic energy developed by the arms is used to increase their potential energy at take-off but also to store and return energy from the lower limbs and to “pull” on the rest of the body. These latter two mechanisms become more important as jump height increases with the pull being the more important of the two. We conclude that an arm swing contributes to jump performance in submaximal as well as maximal jumping but the energy generation and dissipation sources change as performance approaches maximum. 相似文献
15.
随着现代科学技术的成熟发展,神经调控技术逐渐从医学领域拓展至体育领域。在体育领域应用中,主要以无创神经调控技术为主要干预方式,通过电或磁等无创性手段对大脑皮层进行调节,影响神经系统功能进而提高运动功能水平。采用文献综述法对体育领域中神经调控技术研究进行述评,发现神经调控技术有助于增强运动技能学习效果、提高运动技能表现水平、促进运动康复效果,主要采用无创神经调控技术中的经颅交流电刺激（t ACS）、经颅直流电刺激（tDCS）、重复经颅磁刺激（r TMS）进行调控。未来还需结合神经生理学或影像学等技术进行深入研究,并拓展对复杂体育技能的应用。 相似文献
16.
The authors examined the individual and combined influences of 2 factors that have been shown to benefit motor learning: an external focus of attention and enhanced performance expectancies. Another purpose of this study was to gain further insight into the mechanisms underlying these variables. In a factorial design, participants learning a novel motor skill (i.e., throwing with the non-dominant arm) were or were not given external focus instructions, and were or were not provided bogus positive social-comparative feedback to enhance their expectancies. This resulted in 4 groups: external focus, enhanced expectancy, external focus/enhanced expectancy and control. External focus instructions and enhanced expectancies had additive benefits for learning: the external focus/enhanced expectancy group demonstrated the greatest throwing accuracy on both retention and transfer tests, while the accuracy scores of the external focus and enhanced expectancy groups were lower, but higher than those of the control group. Furthermore, self-efficacy was increased by both external focus and enhanced expectancy, and predicted retention and transfer performance. Positive affect was heightened in the enhanced expectancy and external focus/enhanced expectancy groups after practice and predicted transfer performance. The findings suggest that the learning benefits of an external focus and enhanced expectancies mediate learning through partially different mechanisms. 相似文献
17.
Abstract The article by Richard A. Schmidt is directed to the locus of movement control. The paper's major goal is to describe a reconciliation between the peripheralists and the centralists. Schmidt describes major research issues for the future, along with current thinking about the central control of action in various theoretical conceptualizations of the structure of central motor programs. In the presentation on motor skill automation George E. Stelmach and Douglas D. Larish introduce the concept of attention and review research findings concerning attention, automation, and movement. They recommend automatic sequencing as a more viable theoretical position. Empirical support is given for the stance taken by these authors, followed by examples of potential approaches to research in motor behavior. 相似文献
18.
Heather Sykes 《Sport, Education and Society》2013,18(2):127-139
The article uses an episode from the television series ‘The Sopranos’ to illustrate how embodied experiences of sporting practices such as high-school football involve both conscious and unconscious dynamics. It outlines how cultural practices such as masculinist sport are psychically incorporated into the body through the process of identification. The article uses Freud's concept of identification to explain how fantasy and representation are involved in the formation of embodied subjectivity. Contemporary queer theories about identification provide insights into how psychic dynamics both reinforce and undermine the illusory cultural promise of heteronormative whiteness offered by high-school sport and physical education. 相似文献
19.
体育训练中的神经运动控制 总被引：2，自引：0，他引：2
综述运动控制理论中以运动控制模式区分的3个学说:反射运动控制学说、阶梯运动控制学说和系统运动控制学说。并对体育训练中与动作控制有关的感觉系统及运动认知理论、神经系统及记忆痕迹理论、运动系统及自然物理学理论和系统科学观进行阐述。提出:在体育训练中应把感觉经验、认知因子掺入系统功能训练中,以达到最优的运动生理适应性和最佳的运动成绩。 相似文献
20.
Motor imagery (MI) has received a lot of interest during the last decades as its chronic or acute use has demonstrated several effects on improving sport performances or skills. The development of neuroimagery techniques also helped further our understanding of the neural correlates underlying MI. While some authors showed that MI, motor execution and action observation activated similar motor cortical regions, transcranial magnetic stimulation (TMS) studies brought great insights on the role of the primary motor cortex and on the activation of the cortico-spinal pathway during MI. After defining MI and describing the TMS technique, a short report of MI activities only at cortical level is provided. Then, a main focus on the specificities of cortico-spinal modulations during MI, investigated by TMS, is provided. Finally, a brief overview of sub-cortical mechanisms gives importance to the activation of peripheral neural structures during MI. 相似文献