The Metabolic Cost of Two Ranges of Arm Position Height with and without Hand Weights during Low Impact Aerobic Dance

Abstract

To determine the energy cost of low impact aerobic dance while varying arm movement height and the use of hand weights, 10 adults volunteered to participate in four choreographed trials. All trials consisted of identical leg movements. Arm movements, however, were performed above shoulder level both with and without 0.9-kg hand weights and below shoulder level both with and without 0.9-kg hand weights. Open circuit spirometry was employed throughout the 10-min videotape guided trials, and heart rate was measured by telemetry. Neither the use of hand weights nor the change in arm position height significantly altered the energy cost of low impact aerobic dance. However, heart rate responses were significantly different. Caution should be observed by aerobics instructors and participants as to the use of heart rate as an indicator of intensity for low impact aerobic dance.     

The Role of Imaginal Processing in the Retention of Visually-Presented Sequential Motoric Stimuli

Abstract

The purpose of the present study was to investigate the role of imagery in the short term retention of complex, visually-presented movement sequences. Twenty-eight high visual imagers (HIGHS) and 29 low visual imagers (LOWS) viewed and subsequently reproduced movement sequences consisting of eight component moves. Subjects reproduced six such sequences in each of two randomly ordered retention conditions: (1) rehearsal and (2) distraction. Half of the HIGHS and LOWS received instructions to employ imaginal processing strategies, while the other half received no such instructions. Analysis of the data indicated that HIGHS exhibited significantly higher free recall scores than LOWS. In addition, free recall of movement for all subjects was significantly disrupted following performance of a visual distraction task. The findings suggest that visual imagery may have played a functional role in the free recall of modeled movements. However, there was no indication that imagery was involved in the retention of serial information. The findings were explained in terms of the differential processing requirements of free and serial recall memory tasks.     

我国艺术体操集体项目成套动作编排艺术价值的研究

采用录像分析法、数据统计与比较研究法,主要就国内外艺术体操大赛前8名代表队集体项目成套动作编排的艺术价值分类进行统计对比,以探明存在的差距及其成因。研究表明,作为中国艺术体操主攻方向的集体项目,在艺术价值中特殊艺术性加分方面,我国也仅在运动员之间的协作加分的分值上稍有优势,在其他几类特殊性艺术加分上,无论是在选择熟练性运用的类型、器械使用的数量上,还是在独创性加分上,均与世界优秀运动队存在较大差距。     

85 Years Later,RQES Remains Young,Energized, Innovative,and Strong!

Abstract

Subject performed a five-choice reaction time (RT) and movement time (MT) task while walking on a treadmill at heart rates (HR) of approximately 80 (standing still), 115, 145 and 175 beats per minute (bpm). Five-choice RT was optimal at a HR of 115 bpm and worst at 175 bpm, thereby supporting the hypothesis of an inverted U relationship between activation and choice RT. On the other hand, MT improved linearly with increased levels of HR, showing that these two parameters are affected quite differently by concomitant physical exertion.     

Rhythmic Isometric Fatigue Patterns of the Elbow Flexors and Knee Extensors

Abstract

Twenty-seven male subjects performed two 5-min bouts of rhythmic, isometric elbow flexion and two similar bouts of knee extension at a rate of 30 maximal contractions per min. Exponential analyses revealed that the pattern of fatigue for each limb followed a single component curve of the form: Y_t = a₀e ^?Kot + c. An analysis of variance comparing the results from the two limbs revealed that (a) the strength scores for the leg were significantly (p < .05) higher than those for the arm throughout the exercise bouts; (b) both limbs experienced a significant strength decrement; and (c) there was significant interaction between trials and limbs. It appeared that the greater loss of strength by the knee extensors was reponsible for this interaction. It was concluded that during a rhythmic, all-out task, the rates of fatigue experienced by the two muscle groups tend to differ, with the elbow flexors fatiguing more rapidly initially but reaching a plateau at a relatively higher level than the knee extensors.     

Changes in limb striking pattern: effects of speed and accuracy

This study investigated the changes in an arm striking pattern as a result of practice and the effects of speed and accuracy requirements on such changes. The task was to strike a baseball-size foam ball from a batting tee adjusted to the height of each subject's iliac crest. Ten righthanded subjects, initially displaying an inefficient striking pattern, volunteered for this study. All subjects performed the task according to the following conditions: (1) speed, (2) accuracy, and (3) speed and accuracy. Each subject completed 10 trials in each condition (randomly ordered) for five consecutive days. A high-speed camera (64 fps) was used to photograph subjects' striking patterns for each condition over the 5-day period. Analysis of variance of joint angles at arm reversal and contact and velocity of hand relative to the glenohumeral axis at contact revealed that subjects initially constrained limb segments to act in a unitary fashion; then, with practice, a more efficient pattern was developed. The requirement of speed was found to enhance a change in limb configuration, whereas the requirement of accuracy, and subsequent reduction in speed, impeded the development of a more efficient striking pattern. Analysis of radial error revealed no differences in accuracies to the target by either condition or day of practice. A graphic analysis of segmental angular momentum versus relative time showed that joint angle changes allowed subjects to transfer angular momentum and thereby increase the velocity of the hand at contact.     

Short-Term Effects of Midseason Coach Turnover on Team Performance in Soccer

Abstract

Tests were made with the hand carrying weights of 0.2, 3.1, and 16.6 kg. during a 72° horizontal adductive arm swing of maximal speed timed at 12° intervals. Five practice swings and 20 trials, under each condition, were performed by 60 male subjects. Reliability coefficients were high. The first 24° of movement exhibited declining acceleration, followed by linearly increasing acceleration for the 24°—60° interval and deceleration for the next 12°. Compared with static strength in the movement position, action strength computed from acceleration was much greater with the heaviest weight and considerably less with the light weights. The correlation between static strength and speed was quite low for the normal arm swing but increased with added weight, becoming r = .76 for the heaviest. There was little correlation of individual differences in speed between different phases of movement or between movements with light and heavy weights. Specificity was high, although correlations were made for attenuation.     

卡通操对中学生智力发展的影响

坚持采用动作不对称、变化复杂、节奏快速为主要特点的卡通操进行锻炼，能否对中学生的智力发展与学习成绩的提高有促进作用?实验研究表明，答案是肯定的，卡通操锻炼是发展中学生智力的一种有效手段。     

Visually and acoustically augmented performance feedback as an aid in motor control learning: a study of selected components of the rowing action

The present work compares the efficiency of two training techniques as aids to learning selected aspects of a sequentially ordered action such as that of rowing. Subjects in one group were trained with a conventional learning technique (CLT) while those in a second group were trained by an augmented feedback technique referred to as external feedback (EFB). Progress was recorded on learning curves. Rowing athletes with limited experience and psychophysiology students were used for the study. The tasks consisted of learning movement timing (rhythmicity of action and coordination of body parts) and movement intensity (force and electromyogram development), in four separate experiments. The learning curves for EFB subjects were found to have significantly and consistently higher slopes than those for CLT subjects. Optimal criteria were reached by EBF subjects, after a continuous increase in performance levels and a concomitant decrease in standard deviations evaluated from periodicity, movement accuracy and force. Subjects, who after 8 to 10 sessions of CLT learning had not reached optimal level, were exposed to EFB. Their performances then showed a marked improvement and attained the required criterion in 2 to 4 sessions. This further demonstrates the efficacy of EFB as compared with CLT, as an aid to learning a complex sensorimotor action. The efficacy of EFB as a learning technique is discussed in relation to the internal model of the task to be executed and to sensory motor control and motor programmes.     

The Role of Interference and Task Similarity on the Acquisition,Retention, and Transfer of Simple Motor Skills

Abstract

The aim of the present study was to determine if two levels of task similarity influenced acquisition, retention, and transfer performance of three simple motor skills. Sixty right-handed subjects were randomly assigned to one of five (n = 12) experimental conditions. Each subject performed 72 trials during acquisition. Twenty-four trials were recorded for each movement task. Following a 5-min unfilled retention interval, subjects performed 4 trials on each task before completing 12 transfer trials of a novel movement. Contextual interference effects for acquisition and retention were supported for low but not high similarity tasks. Further, the results suggest that a different memory representation exists for high and low similarity tasks.     

Attentional Demands on Motor-Respiratory Coordination

Athletic performance requires the pacing of breathing with exercise, known as motor-respiratory coordination (MRC). In this study, we added cognitive and physical constraints while participants intentionally controlled their breathing locations during rhythmic arm movement. This is the first study to examine a cognitive constraint on MRC. Cognitive constraints included either instruction (Experiments 1 and 2) or signal detection (Experiment 1). Physical constraints were nonoptimal movement frequencies (Experiment 2). Instruction shifted breathing locations and both shifted and increased variability in the number of movements produced per breath (frequency ratio). Signal detection had no effect on MRC. Fast movement frequency resulted in higher, more variable frequency ratios. Cognitive and physical constraints can generate unnatural and variable breathing during athletic performance.     

Influence of Motor and Sensory Sets on Reaction Latency and Speed of Discrete Movements

Abstract

College men and women were tested as to reaction time and speed of an arm movement using both motor-oriented and stimulus-oriented set. The results confirmed a hypothesis based on neuromotor coordination theory that predicted slower movement and greater reaction latency when the motor set was used. However, the 20 percent of subjects who had a natural motor set tendency moved faster with an enforced motor set than with an enforced sensory set. The conditions of enforced set caused a moderate positive correlation between reaction and movement times. Women subjects reacted and moved slower than men, but were similarly influenced by the two enforced set conditions. Their natural set tendency was definitely stimulus-oriented, while men tended to have a neutral orientation.     

Exploratory factor analysis of the functional movement screen in elite athletes

The functional movement screen is developed to examine individuals’ movement patterns through 7 functional tasks. The purpose of this study was to identify the internal consistency and factor structure of the 7 tasks of the functional movement screen in elite athletes; 290 elite athletes from a variety of Chinese national teams were assessed using the functional movement screen. Cronbach’s alpha was calculated for the scores of the 7 tasks. Exploratory factor analysis was performed to explore the factor structure of the functional movement screen. The mean and standard deviation of the sum score were 15.2 ± 3.0. A low Cronbach’s alpha (0.58) was found for the scores of the 7 tasks. Exploratory factor analysis extracted 2 factors with eigenvalues greater than 1, and these 2 factors explained 47.3% of the total variance. The first factor had a high loading on the rotatory stability (loading = 0.99) and low loadings on the other 6 tasks (loading range: 0.04–0.34). The second factor had high loadings on the deep squat, hurdle step and inline lunge (loading range: 0.46–0.61) and low loadings on the other 3 tasks (loading range: 0.12–0.32). The 7 tasks of the functional movement screen had low internal consistency and were not indicators of a single factor. Evidence for unidimensionality was not found for the functional movement screen in elite athletes. More attention should be paid to the score of each task rather than the sum score when we interpret the functional movement screen scores.     

The role of interference and task similarity on the acquisition, retention, and transfer of simple motor skills

The aim of the present study was to determine if two levels of task similarity influenced acquisition, retention, and transfer performance of three simple motor skills. Sixty right-handed subjects were randomly assigned to one of five (n = 12) experimental conditions. Each subject performed 72 trials during acquisition. Twenty-four trials were recorded for each movement task. Following a 5-min unfilled retention interval, subjects performed 4 trials on each task before completing 12 transfer trials of a novel movement. Contextual interference effects for acquisition and retention were supported for low but not high similarity tasks. Further, the results suggest that a different memory representation exists for high and low similarity tasks.     

Anticipation in squash: Differences in advance cue utilization between expert and novice players

The time of occurrence and spatial location of the advance cues used to anticipate the direction and force of an opponent's stroke in squash were examined using a film task. This task, designed to simulate the normal perceptual display of the defensive player, consisted of two discrete parts, each containing 160 individual stroke sequences (trials). In the first part of the film task, the display was occluded at different time intervals throughout the development of the opponent's stroke and the 16 expert and 20 novice subjects had to predict both the direction (down‐wall or cross‐court) and force (drive or drop shot) of the opponent's stroke. In the second part of the film task, visibility to selected advance cues was occluded by placing opaque mats on the film surface. Across all of the film task conditions experts were superior to novices in predicting the event outcome from the information available, highlighting the important contribution anticipatory skills make to expert performance in this sport. Analysis of lateral (direction) error showed that the most critical time periods for extracting information about stroke direction are the periods between 160–80 ms prior to racket‐ball contact and the period of extended ball flight arising at least 80 ms after contact. Whereas both groups were attuned to this ball flight information, only the experts were capable of picking up information from the early part of the opponent's actions. This early information appeared to be provided by the opposing player's arm action. Similar time periods were found to be also important for the prediction of stroke depth, but in this case both experts and novices were similar in their cue dependence.     

国家艺术体操队运动员功能动作筛查结果分析与纠正性训练

目的：对国家艺术体操队22名运动员进行功能动作筛查并分析,了解该项目运动员的功能动作特征,并针对存在问题的功能动作提出纠正性训练方法,以期达到改善功能动作质量、减少损伤发生、提高专项训练水平的目的。方法：文献资料法、实验法、数理统计法、逻辑分析法。结果：（1）队员的FMS得分为13.0±2.5分,存在较大的损伤风险;（2）主动直膝抬腿、肩部灵活性、躯干稳定俯卧撑得分与其他动作相比具有显著性差异;（3）共有23人次在测试中存在疼痛,7人次存在不对称现象。结论：国家艺术体操运动员：（1）髋、肩关节灵活性较好而踝关节则较差,部分运动员腰椎灵活性过度而胸椎灵活性受限;（2）髋关节、肩胛区及核心区稳定性较差;（3）小腿三头肌柔韧性差,踝关节和髋关节外展、内收肌力失衡,部分运动员下肢不对称。纠正性训练应首先根据排序原则进行排序,其次从灵活性、稳定性、功能性力量、动作模式重建这4个方面开展针对性的训练。最后,8周的纠正性训练显著地提高了FMS得分,功能动作质量得到改善。     

The effects of anxiety upon psychomotor performance

This paper describes an experiment which examined the effects of anxiety on choice reaction time and movement time. A balanced repeated measures design was adopted in which eight female subjects performed a six-choice visual reaction task in 'no anxiety' and 'anxiety' conditions. The anxiety condition required subjects to jump from a balcony 15 feet (4.57 m) into a foam-filled pit below. Subjects in the anxiety condition demonstrated significantly higher levels of cognitive anxiety and longer reaction times than those in the no anxiety condition. The analysis of the reaction time data also revealed a significant interaction between anxiety and block. No significant effects emerged in the case of movement time.     

Feedback and Skill Learning

Abstract

This study was an investigation of the course of learning a specified arm movement pattern under conditions that varied as to the type and frequency of feedback information. After several days of practice, subjects performed a criterion test which was the same as the learning movement pattern, but explicit visual feedback was withdrawn.

Forty undergraduate students were divided into five groups. Each group was randomly assigned a method of learning the task. The methods of receiving information about performance were as follows: (a) concurrent visual feedback, (b) concurrent proprioceptive feedback and terminal knowledge of graphs, (c) a combination of (a) and (b), (d) concurrent visual feedback interspersed with passive watching, and (e) concurrent visual feedback at two different speeds.

The results indicated the following: (a) the most effective variable for learning the pattern was concurrent visual feedback, (b) performing the movement at a slower than normal rate was detrimental to performance on the criterion test, (c) sitting and watching was as effective a learning method as performing at two speeds, and (d) subjects in the slow-standard speed group were significantly poorer than subjects in other groups during performance of the criterion test. The other methods did not differ significantly from each other.     

The metabolic cost of two ranges of arm position height with and without hand weights during low impact aerobic dance.

To determine the energy cost of low impact aerobic dance while varying arm movement height and the use of hand weights, 10 adults volunteered to participate in four choreographed trials. All trials consisted of identical leg movements. Arm movements, however, were performed above shoulder level both with and without 0.9-kg hand weights and below shoulder level both with and without 0.9-kg hand weights. Open circuit spirometry was employed throughout the 10-min videotape guided trials, and heart rate was measured by telemetry. Neither the use of hand weights nor the change in arm position height significantly altered the energy cost of low impact aerobic dance. However, heart rate responses were significantly different. Caution should be observed by aerobics instructors and participants as to the use of heart rate as an indicator of intensity for low impact aerobic dance.     

The effects of anxiety upon psychomotor performance

This paper describes an experiment which examined the effects of anxiety on choice reaction time and movement time. A balanced repeated measures design was adopted in which eight female subjects performed a six‐choice visual reaction task in ‘no anxiety’ and ‘anxiety’ conditions. The anxiety condition required subjects to jump from a balcony 15 feet (4.57 m) into a foam‐filled pit below. Subjects in the anxiety condition demonstrated significantly higher levels of cognitive anxiety and longer reaction times than those in the no anxiety condition. The analysis of the reaction time data also revealed a significant interaction between anxiety and block. No significant effects emerged in the case of movement time.