Specific Motor Performance Research Articles

EXAMINATION OF FUNCTIONAL MOVEMENT STATUS, INJURY HISTORY AND SPECIFIC MOTOR PERFORMANCE AMONG YOUNG ELITE FOOTBALL PLAYERS

Purpose: The primary aim of this study was to find any relationship between total and selected FMS scores, recent (within two years) injury status, and specific motor performance. The secondary purpose of the study was to examine, wheather is there any relationship between injuries of the hamstring muscle and injuries of the hip and knee joints of the body.
 Material and methods: Youth and junior football players were volunteered to take part in our examination. A total of 45 subjects participated in our study, their age varied from 16 to 19. We implemented a five to one scoring system to identify the status of injuries. Finally, a complete FMS testing and a single leg (unilateral) standing long jump test were performed, involving all participants.Beside evaluating the total FMS scores of the participants, we chose to specifically stress on five test batteries out of seven. Out of the five tests we further focused on three FMS tests.
 Results and conclusion: In this given population, we have not found significant relationship between total FMS scores and overall scores (5 to 1) of injury status. Our results also did not indicate any significant correlation between selected FMS scores and single leg standing long jump performance.

Talent selection in youth football: Technical skills rather than general motor performance predict future player status of football talents

Recommended multidimensional models for talent selection are difficult to implement for practitioners in the field. Furthermore, their application has not been established from a scientific point of view, with a lack of clarity concerning how to integrate manifold test results with respect to loading, interaction, and compensation phenomena. Consequently, the question of powerful single predictors for future player status are still of interest within talent research in order to determine promising content for less extensive selection procedures. The aim of the current study is an immediate comparison of the prognostic validity of two frequently used areas within talent selection in youth football: general motor performance (e.g., speed and endurance) and specific motor performance (i.e., technical skills). Participants completed four general and four specific motor performance tests at early adolescence (U13/U14, 133 players) and middle adolescence (U16/U17, 85 players). The area under the curve (AUC) from the receiver operating characteristic was used to compare the prognostic validity of both motor performance areas (predicting U20 player status: professional vs. non-professional). Although no comparison at the four different age levels led to a significant difference (.07 ≤ p ≤ .65), there was a continuous superiority of specific over general motor performance in descriptive AUC values. These descriptive differences reached relevant extent within early adolescence (ΔAUCU13 = .09; ΔAUCU14 =.14) and were partially accounted for by the influence of biological maturation. In line with theoretical considerations and earlier research, these results provide further evidence of the superiority of specific over general motor performance in predicting future player status. Until the applicability of multidimensional models is further established, specific motor performance rather than general performance should be included in less extensive talent selection models, especially in early adolescence.

Physiological, Anthropometric, and Motor Characteristics of Elite Chinese Youth Athletes From Six Different Sports.

Several talent selection programs in elite sport schools are based on motor diagnostics for the purpose of recommending or transferring promising talents to general groups of sports; game sports, combat sports or endurance sports, and to more concrete sports such as gymnastics, skiing, or tennis. However, the predictive value of such testing is unclear. This study evaluated the concurrent validity of physiological performance prerequisites, body dimensions, as well as specific motor performances. The sample consisted of N = 97 youth athletes from all ninth grade classes of a Shanghai Elite Sport school belonging to six different sports including basketball (n = 7), fencing (n = 23), judo (n = 20), swimming (n = 10), table tennis (n = 15), and volleyball (n = 22). The performance diagnosis took place between September 2016 and March 2017, and comprised five physiological measurements of the heart rate at rest, vital capacity, systolic and diastolic blood pressure, and hemoglobin concentration in the blood, eighteen anthropometric parameters, and two motor tests on back strength and complex reaction speed. The aim of the study was to investigate whether U15 age group athletes participating in six different sports already at this age show a sport specific anthropometric, motor performance, and physiological profile which is in line with the specific requirements of each of the sports. A discriminant analysis and a Neural Network (Multilayer Perceptron) were used to test whether it is possible to discriminate between athletes of the six sports and to assign each individual of the Under-15 athletes to his own sport on the basis of a unique profile of the morphological, motor, and physiological prerequisites. All diagnostic methods exhibited medium to high validity to discriminate between the six different sports. The relevance of the eighteen body dimensions, five physiological measures, and two motor tests for talent identification was confirmed.

The "Brain to Behavior Approach" to diagnosis and treatment.

Sadly, the Decade of the Brain has passed, an exciting time that seemed to promise the long awaited identification of psychiatric biological markers (1). Despite the significant advances in brain imaging and biochemical techniques such as genetic mapping, we failed to achieve greater accuracy in our diagnostics or more personalized care for patients with psychiatric conditions. Even now, we search for that Holy Grail of mental health, a specifically sensitive clinical biological marker for psychiatric diagnosis, and as we have continued to search, we have discovered that the mental health profession struggles to think outside its box. Perhaps our persistent avoidance of empirical data has constrained our creativity, making it difficult for the various theoretical silos to reflect upon their clinical weaknesses. Historically, we have convinced ourselves that we can know and diagnose our patients simply by scrutinizing their symptoms and correlating them with specific underlying biological disturbances. Although this may be true when a specific well-defined brain lesion involves specific sensory systems, for example when blindness results from a visual pathway lesion, it may be quite uncertain when frontal lobe or basal ganglia lesions silently interfere with mood and cognition without disturbing specific motor performance (2). As such, when we search for the unique biological marker for a single psychiatric diagnostic category, we set ourselves up for failure. Despite research eventually discrediting all initial leads that promised to find a particular diagnostic marker, their efforts were not in vain. Today we have re-evaluated certain measures only to discover new utilities. Current examples of such rediscovered tools are quantitative EEG, which despite its less than stellar beginnings is showing clear clinical applications in psychiatric diagnosis (3,4) and cortisol, which now appears as a marker for depression (5) and, perhaps, posttraumatic stress disorder (6-10).

Sequence Specific Motor Performance Gains after Memory Consolidation in Children and Adolescents

Memory consolidation for a trained sequence of finger opposition movements, in 9- and 12-year-old children, was recently found to be significantly less susceptible to interference by a subsequent training experience, compared to that of 17-year-olds. It was suggested that, in children, the experience of training on any sequence of finger movements may affect the performance of the sequence elements, component movements, rather than the sequence as a unit; the latter has been implicated in the learning of the task by adults. This hypothesis implied a possible childhood advantage in the ability to transfer the gains from a trained to the reversed, untrained, sequence of movements. Here we report the results of transfer tests undertaken to test this proposal in 9-, 12-, and 17-year-olds after training in the finger-to-thumb opposition sequence (FOS) learning task. Our results show that the performance gains in the trained sequence partially transferred from the left, trained hand, to the untrained hand at 48-hours after a single training session in the three age-groups tested. However, there was very little transfer of the gains from the trained to the untrained, reversed, sequence performed by either hand. The results indicate sequence specific post-training gains in FOS performance, as opposed to a general improvement in performance of the individual, component, movements that comprised both the trained and untrained sequences. These results do not support the proposal that the reduced susceptibility to interference, in children before adolescence, reflects a difference in movement syntax representation after training.

Relationship between extremities in motor performance.

The purpose of the study was to examine the relationship between the extremities in different aspects of motor performance, including simple reaction time, choice reaction time, speed of movement, tapping speed, and coordination, i.e., speed of movement/accuracy. 186 healthy randomly selected right-handed subjects (93 men, 93 women; aged 21-70 years) were measured on a test battery of five tests for both hands and feet. Correlations between the extremities in motor performance were highest between hands (r=.71-.80, p<.001) or between feet (r=.57-.88, p<.001) depending on the complexity of response for all subjects. These relations remained at almost the same magnitude even when age was eliminated. Correlations between the upper and lower extremities were lower (r = .40-.62). Correlations between extremities were lower for one age group (21-30 years) than for all subjects (21-70 years). These results showed that the motor performance for the hands is not a very good indicator of the motor performance of the lower extremities, especially in a homogeneous age group, and it seems that the lower extremities should be studied with specific motor performance tests.

Retroambiguus projections to the cutaneus trunci motoneurons may form a pathway in the central control of mating.

Our laboratory has proposed that the nucleus retroambiguus (NRA) generates the specific motor performance displayed by female cats during mating and that it uses direct pathways to the motoneurons of the lower limb muscles involved in this activity. In the hamster a similar NRA-projection system could generate the typical female mating posture, which is characterized by lordosis of the back as well as elevation of the tail. The present study attempted to determine whether this elevation of the tail is also part of the NRA-mating control system. The basic assumption was that elevation of the tail is a function of the cutaneous trunci muscle (CTM), which was verified by bilateral tetanic stimulation of the lateral thoracic nerves innervating the CTM. It resulted in upward movement of the tail to a position similar to the tail-up position during the lordosis posture. Retrograde tracing results showed that CTM motoneurons are located in the ventral and ventrolateral part of the C(7)-C(8) ventral horn, those innervating the tail region ventrolateral to those innervating the axillary region. Anterograde tracing studies showed that NRA fibers terminate bilaterally in both parts of the CTM motoneuronal cell groups. Electron microscopical studies revealed that labeled NRA terminals make monosynaptic contacts with retrogradely labeled dendrites of CTM motoneurons. Almost all of these terminal profiles had asymmetric synapses and contained spherical vesicles, which suggests an excitatory function. The observation that 15% of the labeled NRA terminals make more than one synaptic contact with a retrogradely labeled CTM motoneuronal dendrite within the same section indicates how powerful the NRA-CTM projection is. The results indicate that during mating the NRA not only could generate the lordosis posture but also the elevation of the tail.

Reliability comparison between standard and energy efficient motors

There are always tradeoffs when maximizing a specific motor performance parameter such as efficiency. The purpose of this paper is to compare the various performance parameters and elements which determine motor reliability. The impact on motor life is considered, along with its robustness. Only the three-phase squirrel-cage induction motors covered by the 1992 Energy Act are covered in this presentation, as compared to standard motors.

SELECTED MOTOR SKILLS OF MENTALLY RETARDED AND NONRETARDED INDIVIDUALS

The aim of this study was to examine whether mentally retarded individuals show a specific motor performance deficit on measures of reaction time, aiming, and dexterity. 23 mentally retarded adolescents and two control groups of 22 non-retarded persons of the same mental age and 20 nonretarded persons of the same chronological age were tested. Motor performance measures for retarded persons were considerably longer than those of nonretarded persons of the same chronological age and of the same mental age. Only time of finger dexterity with short pins was longer for the retarded than for the nonretarded adolescents of the same mental age. Reaction times across groups were faster for the sound than for the light signal. No difference in RT for fine movement was observed. Differences among the various motor performance measures for retarded and nonretarded subjects are confirmed.

Circadian rhythm in rat H-reflex

We measured soleus H-reflex in the Sprague-Dawley rat as a function of time of day. H-reflex amplitude displayed a marked diurnal variation, even though background EMG and M-response amplitude were stable through the day. The H-reflex was largest in the late morning and smallest around midnight. Thus, its rhythm was opposite in phase to the circadian rhythm found in the primate H-reflex. This rhythm is a potentially confounding factor in studies of motor function. Furthermore, its existence implies that the CNS activity underlying a specific motor performance varies with time of day.

Selected Motor Skills of Mentally Retarded and Nonretarded Individuals

The aim of this study was to examine whether mentally retarded individuals show a specific motor performance deficit on measures of reaction time, aiming, and dexterity. 23 mentally retarded adolescents and two control groups of 22 non-retarded persons of the same mental age and 20 nonretarded persons of the same chronological age were tested. Motor performance measures for retarded persons were considerably longer than those of nonretarded persons of the same chronological age and of the same mental age. Only time of finger dexterity with short pins was longer for the retarded than for the nonretarded adolescents of the same mental age. Reaction times across groups were faster for the sound than for the light signal. No difference in RT for fine movement was observed. Differences among the various motor performance measures for retarded and nonretarded subjects are confirmed.