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1.
Frances J. Brannon David L. Kelley William J. Tomik 《Research quarterly for exercise and sport》2013,84(2):402-404
Abstract The use of the motor-driven belt treadmill for small animal research in exercise physiology is becoming increasingly more prominent. Treadmill devices are usually constructed to meet the needs of specific experiments and, therefore, several different kinds have been described in research publications (1, 2, 3, 4, 5, 6, 7). Cost is a not uncommon difficulty in the acquisition of such devices with typical units ranging from approximately $300 to $1,000. The treadmill device described herein has several worthwhile features; one of which is its low cost. In addition, the quiet operating apparatus allows the forced running of several small animals at a time within a wide variation of belt speeds. 相似文献
2.
面对新型冠状病毒肺炎疫情的爆发,网络体育健身视频成为体育抗疫的"急先锋",对其持续使用意愿影响因素进行分析可为推进体育产业和全民健身事业发展提供借鉴。基于使用与满足理论视角,通过问卷调查和结构方程模型构建影响因素研究模型,针对典型群体进行实证分析。结果表明:1)使用与满足理论适用于网络体育健身视频研究,并有着较强的解释力;2)信息需求、社交需求、好奇心的满足感正向影响网络体育健身视频用户的积极情绪获取;3)积极情绪显著正向影响网络体育健身视频用户的持续使用意愿。实践启示:1)提升网络体育健身视频信息质量;2)优化网络体育健身的社交功能;3)开发网络体育健身视频的眼球效应。 相似文献
3.
Brian Thomas Weaver Kathleen Fitzsimons Jerrod Braman 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(3):370-384
The goal of the current study was to expand on previous work to validate the use of pressure insole technology in conjunction with linear regression models to predict the free torque at the shoe–surface interface that is generated while wearing different athletic shoes. Three distinctly different shoe designs were utilised. The stiffness of each shoe was determined with a material’s testing machine. Six participants wore each shoe that was fitted with an insole pressure measurement device and performed rotation trials on an embedded force plate. A pressure sensor mask was constructed from those sensors having a high linear correlation with free torque values. Linear regression models were developed to predict free torques from these pressure sensor data. The models were able to accurately predict their own free torque well (RMS error 3.72 ± 0.74 Nm), but not that of the other shoes (RMS error 10.43 ± 3.79 Nm). Models performing self-prediction were also able to measure differences in shoe stiffness. The results of the current study showed the need for participant–shoe specific linear regression models to insure high prediction accuracy of free torques from pressure sensor data during isolated internal and external rotations of the body with respect to a planted foot. 相似文献
4.
F. Javier Núñez Carlos Galiano Alejandro Muñoz-López Pablo Floria 《Journal of sports sciences》2020,38(14):1624-1628
ABSTRACT The aims of this study were to compare the force profile of using a horizontal cylinder-shaped axis or a vertical cone-shaped axis to provide resistance in rotary inertia devices, and to report the evolution of kinetic and kinematic variables in experienced athletes during a half-squat exercise. Twenty-two healthy active men participated in the assessment of time, peak velocity, peak force, time to reach the peak force, average force, impulse, and range of movement, during a half-squat incremental test performed on conical inertial device (CP) and on cylinder inertial device (YY). The analysis showed that YY during CON-ECC phased generates substantial higher peak_force, mean_force, impulse, time, and a lower peak_velocity, than CP. We never obtained eccentric overload for peak_force or mean_force. CP offers less resistance to accelerate-decelerate the movement with respect to YY, we need checking whether eccentric overload it is being produced, and the impulse was the only kinetic variable that was able to discriminate between the inertias and devices. 相似文献
5.
在全球新冠疫情的影响下，本研究探讨了在线教学下应用视频反馈法提高网球技术教学的效果，对丰富网球在线教学手段、提升在线教学效果具有理论与现实意义。本研究以高校选修网球课程的大学生为实验对象，运用文献资料法、问卷调查法、实验法、数理统计法等，对视频反馈法如何改善在线教学效果进行分析。研究认为：在线教学环境下，视频反馈法能够显著促进大学生网球学习初期正反手技术的形成。同时，自主控制反馈内容更利于激发大学生的自我效能感，从而有效地提升网球技术的在线教学效果。 相似文献
6.
Maddison J. Jones Brian Dawson Daniel F. Gucciardi Peter R. Eastwood Joanna Miller Shona L. Halson 《Journal of sports sciences》2019,37(8):864-870
The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (B = -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (B = 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness. 相似文献
7.
采用ME6000表面肌电仪和SONY高速摄像机对沈阳体育学院9名优秀速度滑冰运动员在模拟滑道训练中进行同步分析。结果表明：速度滑冰运动员侧蹬腿与支撑腿表面肌电原始电压有显著差异,左右伸膝肌群（腓外、腓内）在滑行过程中放电高于其他肌群;左腿为侧蹬腿时,半腱肌在膝关节折叠成小角度时放电最为明显;双支撑阶段右腿屈伸肌群表面肌电标准化电压在膝关节角为110～120°时达到最大值,在膝关节角大于120°之后肌肉力量降低明显。 相似文献
8.
Róisín M. Howard Richard Conway Andrew J. Harrison 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(1):1-17
The use of electromyography (EMG) is widely recognised as a valuable tool for enhancing the understanding of performance drivers and potential injury risk in sprinting. The timings of muscle activations relative to running gait cycle phases and the technology used to obtain muscle activation data during sprinting are of particular interest to scientists and coaches. This review examined the main muscles being analysed by surface EMG (sEMG), their activations and timing, and the technologies used to gather sEMG during sprinting. Electronic databases were searched using ‘Electromyography’ OR ‘EMG’ AND ‘running’ OR ‘sprinting’. Based on inclusion criteria, 18 articles were selected for review. While sEMG is widely used in biomechanics, relatively few studies have used sEMG in sprinting due to system constraints. The results demonstrated a focus on the leg muscles, with over 70% of the muscles analysed in the upper leg. This is consistent with the use of tethered and data logging EMG systems and many sprints being performed on treadmills. Through the recent advances in wireless EMG technology, an increase in the studies on high velocity movements such as sprinting is expected and this should allow practitioners to perform the analysis in an ecologically valid environment. 相似文献
9.
J.P. Clarys L. van Puymbroeck J. Publie E. Bollens J. Cabri B. de Witte 《Journal of sports sciences》2013,31(2):129-139
The purpose of this study was to examine whether differences in construction between the compact ski, the racing ski and the soft ski influence the behavioural and electromuscular responses of the user. Eight qualified male ski instructors performed two ‘shuss’ trials and three different basic turns. Six muscles (M. biceps femoris, M. gastrocnemius lateralis and medialis, M. rectus femoris, M. vastus lateralis and M. tibialis anterior) were studied, using a conventional but portable electromyographic (EMG) registration with telemetric synchronization, active electrodes and a six‐channel portable data recorder. Muscle contractions were continuously registered and visualized in raw EMG form and linear envelopes. The differences between the mean rectified EMG data of dynamic contractions while skiing and the mean rectified EMG data of the maximal voluntary contraction were used in the primary analysis of data, from which the participation levels of the muscles investigated could be calculated for each type of ski. Based on this comparison, differences between the effects on muscle activity of the three types of skis were unimportant. In a second phase, the normalized linear envelopes of all subjects were graphically superimposed and averaged. This was performed for each muscle, for each movement, for each leg and for each ski tested. The EMG data were considered in combination with anthropometric values, with snow characteristics and with the velocity of skiing. This study showed systematic differences between the use of the racing, soft and compact ski. On average the soft ski showed the lowest muscle activity patterns and thus the most economical muscular efforts for all muscles investigated and within all movements. 相似文献
10.
J P Clarys L Van Puymbroeck J Publie E Bollens J Cabri B De Witte 《Journal of sports sciences》1986,4(2):129-139
The purpose of this study was to examine whether differences in construction between the compact ski, the racing ski and the soft ski influence the behavioural and electromuscular responses of the user. Eight qualified male ski instructors performed two 'shuss' trials and three different basic turns. Six muscles (M. biceps femoris, M. gastrocnemius lateralis and medialis, M. rectus femoris, M. vastus lateralis and M. tibialis anterior) were studied, using a conventional but portable electromyographic (EMG) registration with telemetric synchronization, active electrodes and a six-channel portable data recorder. Muscle contractions were continuously registered and visualized in raw EMG form and linear envelopes. The differences between the mean rectified EMG data of dynamic contractions while skiing and the mean rectified EMG data of the maximal voluntary contraction were used in the primary analysis of data, from which the participation levels of the muscles investigated could be calculated for each type of ski. Based on this comparison, differences between the effects on muscle activity of the three types of skis were unimportant. In a second phase, the normalized linear envelopes of all subjects were graphically superimposed and averaged. This was performed for each muscle, for each movement, for each leg and for each ski tested. The EMG data were considered in combination with anthropometric values, with snow characteristics and with the velocity of skiing. This study showed systematic differences between the use of the racing, soft and compact ski. On average the soft ski showed the lowest muscle activity patterns and thus the most economical muscular efforts for all muscles investigated and within all movements. 相似文献
11.
Coaches' apparent preferences for informal and self-directed modes of learning have been highlighted in the literature. Consequently, there is a need for innovative coach education approaches that complement these clearly preferred, informal routes and better provide coaches with the professional skills they need to deal with the complex nature of their work. Online blogs are one such tool said to have the potential to strengthen and promote critical thinking and reflection on professional practice; however, research evidence and theoretical frameworks for their use is inconclusive and currently lacking. Therefore, the purpose of part 1 of this two-part investigation was to explore the use of shared online blogs as a tool to promote reflection and community of practice (CoP) in a cohort of 24 undergraduate sports coaching students (5 females, 19 males). Four group blogs, purposely designed to support informal workplace learning, were subjected to content analysis in order to determine the emergent reflective quality of blog entries and the extent to which functioning online CoPs emerged. Findings revealed that shared blogs were a useful tool to promote higher order reflective thinking, and fully functioning online CoPs emerged in all four groups. 相似文献
12.
T. Le Sage A. Bindel P. P. Conway L. M. Justham S. E. Slawson A. A. West 《Sports Engineering》2011,14(1):1-14
The research outlined in this paper was conducted to allow real-time processing, transmission and presentation of data to
swimming coaches and subsequently their swimmers in a training environment, focused on providing information relevant to strokes
in free swimming. This was achieved using a wearable wireless sensor and embedded programming techniques, using accelerations
involved in the swimming stroke to provide relevant features for coaches. Current methods used do not offer real-time response
to coaches, which results in the lack of real-time feedback and significantly increased post-session analysis time. Filtering
and signal processing algorithms are described here, which allow real-time data analysis to be embedded within a wireless
sensor node. The system significantly reduces the time for processing acquired data and has delivered a novel monitoring device
suitable for operation within the harsh environment of the pool. 相似文献
13.
The repeated bout effect refers to the protective effect provided by a single bout of eccentric exercise against muscle damage from a similar subsequent bout. The aim of this study was to determine if the repeated bout was associated with an increase in motor unit activation relative to force production, an increased recruitment of slow-twitch motor units or increased motor unit synchronization. Surface electromyographic (EMG) signals were recorded from the hamstring muscles during two bouts of submaximal isokinetic (2.6 rad x s(-1)) eccentric (11 men, 9 women) or concentric (6 men, 4 women) contractions separated by 2 weeks. The EMG per unit torque and median frequency were analysed. The initial bout of eccentric exercise resulted in strength loss, pain and muscle tenderness, while the repeated eccentric bout resulted in a slight increase in strength, no pain and no muscle tenderness (bout x time effects, P < 0.05). Strength, pain and tenderness were unaffected by either bout of concentric exercise. The EMG per unit torque and median frequency were not different between the initial and repeated bouts of eccentric exercise. The EMG per unit torque and median frequency increased during both bouts of eccentric exercise (P < 0.01) but did not change during either concentric bout. In conclusion, there was no evidence that the repeated bout effect was due to a neural adaptation. 相似文献
14.
研究目的：探讨动力性与静力性肌肉收缩时EMG各参数的变化特征及疲劳时各指标的差异，比较不同项目运动员肌肉收缩特征对EMG参数的影响及与该项目的关系。研究方法：27名受试者分为两组，第一组为赛艇运动员（组一），第二组为田径爆发性力量项目（跳跃、短跑）专选运动员（组二）。受试者以2／3Mvc做静力性持续等长收缩，动力性持续肌肉收缩则采用本人的MVC，同时记录EMG信号，分析IEMG、E／T值和MF。研究结果：持续静力性肌肉收缩时，随疲劳的发展赛艇运动员与田径运动员IEMG、E／T值均显著升高。但赛艇运动员从运动开始至80％时段一直保持平稳，此后迅速上升。静力性收缩时两组运动员随疲劳发展MF从高频向低频转移，但田径运动员频率下降速率要快于赛艇运动员。结论：赛艇运动训练促使大脑皮层动员运动单位工作更具有时间耐久性。快速、爆发式运动使疲劳时大脑皮层兴奋性下降更快，肌肉更易于疲劳。 相似文献
15.
Laura Simoni Guido Pasquini Silvia Pancani Federica Vannetti Claudio Macchi Silvia Pogliaghi 《Journal of sports sciences》2020,38(20):2321-2328
ABSTRACT Studies on running biomechanics and energetics are usually conducted on a treadmill. To ensure that locomotion on a treadmill is comparable to locomotion overground, participants need to be expert in the use of the device. This study aimed to identify the number and duration of sessions needed to obtain stable measurements for spatiotemporal and metabolic parameters in unexperienced treadmill runners. Fourteen male recreational runners performed three 15-min treadmill running trials in different days at a submaximal speed. Spatiotemporal and metabolic parameters were registered at minutes: 5, 10, 15 and their within-trial and between-trial changes were analysed using a two-way repeated measures ANOVA and Bonferroni post-hoc test. Within-trial differences were found in step frequency (decreased over time), Step Length and Contact Time (increased), reaching stability at different time points. Ventilator parameters increased, reaching stability after 5–10 min, while heart rate increased progressively over time. The only between-trial differences were an increase in step length and a decrease in step frequency at min 1, between trials 1 and 3. In conclusion, at least three running trials of 15 min are required to familiarize with the device. The last 5 min of the third trial can be regarded as stable measurements. 相似文献
16.
The control of human limb movement has been the focus of research for more than a century. A major issue to emerge from this work is the manner in which the central nervous system regulates electromyographic (EMG) activity to produce movements that differ in distance, velocity, and movement time. However the different methods of analysis often used to analyze EMG data could result in different kinematic-EMG relationships. In this study, participants performed an elbow flexion task to one of five distance goals (between 5 degrees and 50 degrees) using three movement speeds. EMG data from the right elbow flexors were compared using a trial-by-trial analysis and one based on averaged data. Averaging across trials underestimated biceps EMG amplitude at all movement distances and speeds compared to a trial-by-trial analysis. Averaging overestimated EMG burst duration compared to the trial-by-trial analysis. Peak agonist EMG amplitude was positively related to distance and inversely related to movement time. Agonist EMG duration was constant for movement distances less than 30 degrees but increased in the 50 degrees condition. The results support the view that peak EMG amplitude and duration can be controlled independently, but EMG duration changes only for longer distance movements when additional force is required. 相似文献
17.
《Sport Management Review》2016,19(2):183-197
Brand communities have become an important aspect for brand management in social media. However, many brands have failed to establish a successful online brand community. In this study, we introduce branded communities as an alternative concept to brand communities. In contrast to brand communities, a branded community does not revolve around a specific (sport) brand, but around any interest or need. However, a specific brand makes use of the community for marketing purposes by sponsoring or operating the community. We emphasize the suitability of sport as an interest around which branded communities can be built as well as links of branded communities to sport sponsorship. We empirically studied the factors which influence the success of this phenomenon and the effects of operating or sponsoring such a community for a brand by using an online survey (N = 501) of members of a branded online community relating to football. The results demonstrate the relevance of topic interest (i.e., identification and involvement with football) and the quality of the community as determinants of interest in and loyalty towards a branded community. The brand owner benefits from an increase in brand loyalty for those community members who are aware of the brand as the operator of the community, whereby awareness of this sponsorship does not decrease loyalty towards the community. Our research contributes to previous knowledge by proving that branded communities are both an effective means for companies to deploy sponsorship and branding strategies in social media and provide a promising opportunity for sport managers to generate value. 相似文献
18.
In the presented research, a kinematic and electromyographic study was performed on one world-class male elite handbiker (UCI class H3.2). Activity of 14 muscles of the upper body were measured with surface electromyography (EMG), and a motion analysis of the athlete’s movement was performed concurrently for different backrest positions, crank lengths, and crank heights at three power levels (130, 160 and 190 W). Kinematics in terms of elbow and wrist angle, muscular on-off timing, EMG amplitudes, and integrated EMG were calculated. Results showed that little changes occurred for kinematic parameters and changes in position led to a shift in muscular timing. However, no indication for immediate improvement to the athlete’s preferred original position could be observed. 相似文献
19.
Vertical jump height is thought to provide a valuable index of muscular power, which is an important factor in sports performance and for assessing the mobility and functional capacity of injured or aged individuals. The purpose of the present study was to investigate the criterion validity of four popular devices for measuring vertical jump height. A belt mat, contact mat, portable force plate, and Vertec were compared to a criterion device, a laboratory force plate. Forty participants performed three maximal countermovement jumps on each device in a counterbalanced order, using block randomization. The criterion device presented the highest mean value (50.3 cm). The portable force plate and belt mat devices recorded similar jump height values to the criterion device (within 1 cm). The contact mat and Vertec devices recorded significantly lower values than the criterion device (P < 0.001). The mean difference ± limits of agreement were: belt mat -0.1 ± 5.5 cm, contact mat -11.7 ± 6.4 cm, portable force plate -0.8 ± 3.9 cm, and Vertec -2.4 ± 6.6 cm. In conclusion, the portable force plate and belt mat devices provided valid measures of vertical jump height, whereas the Vertec and contact mat devices did not. 相似文献
20.
The purpose of this study was to explore the dose–response relationship between exercise and cognitive performance using an acute bout of isometric exercise. University students (N = 55) were randomly assigned to control, 30%, 50% and 70% of maximum voluntary handgrip contraction groups. Participants performed a modified Stroop task before and after completion of an isometric handgrip endurance trial at their assigned exercise intensity. Ratings of perceived exertion (RPE) and forearm muscle activation (EMG) showed linear trends of progressively greater RPE and muscle activation at greater exercise intensity levels. Regression analysis showed significant (P < .05) linear degradations in frequency of errors on the Stroop task with increasing exercise intensity. We conclude that performing isometric exercise until exhaustion is associated with reduced cognitive performance and that higher intensity isometric exercise leads to greater performance impairments in a linear dose–response manner. 相似文献