KINEMATIC PARAMETERS OF NODES IN TENNIS SERVE

2020 ◽  
pp. 77-83
Author(s):  
KONSTANTIN K. BONDARENKO ◽  
Anastasiya D. Lebed
Keyword(s):  
Skeletal Muscles ◽  
The Body ◽  
Technical Training ◽  
Structural Elements ◽  
Kinematic Parameters ◽  
Training Process ◽  
Tennis Players ◽  
Tennis Serve ◽  
Biomechanical Parameters ◽  
Motor Actions

Modern sports make high requirements for the implementation of technical elements of the movement. Evaluation of shock actions when serving in big tennis allows you to model the technical training of athletes. The purpose of the article is to determine the kinematic parameters of the movement of body links when performing a pitch in tennis. To perform a motion analysis, we used a knot position method to determine the structural elements of the motion. Depending on the pedagogical tasks, we revealed the main characteristics of the movement using nodes. We determined angular deviations from anatomical positions in joints, between body links performing efficiency of performed action. We revealed the most rational ranges of angular positions between segments of the body. Analysis of biomechanical parameters of movement allows to determine rational trajectories of movement of body links, which makes it possible to select the most effective serving and special exercises aimed at formation of the most effective motor actions and reduction of tension during movement in the player's joints and skeletal muscles. These biomechanical data can then be useful to improve the organization and planning of the training process of tennis players. Knowledge of the range of angular movements and the nature of the change in relative body links helps to reduce joint injuries when serving in tennis.

scholarly journals The influence of skiing and cycling on the coordination abilities of young athletes 10-11 years old

2020 ◽  
pp. 163-167
Author(s):  
M. Prudnikova ◽  
A. Skaliy ◽  
V. Gorinа
Keyword(s):  
Physical Fitness ◽  
Young Age ◽  
Technical Training ◽  
Maximum Efficiency ◽  
Training Process ◽  
Young Athletes ◽  
Extreme Sports ◽  
Functional Features ◽  
The Difference ◽  
Motor Actions

The article presents the indicators of physical fitness and coordination abilities of young athletes 10-11 years old. Under the influence of specific physical loads in accordance with the chosen kind of sport, data on speed and speed- power qualities were obtained, as well as the level of coordination abilities of young athletes of 10-11 years old. Objective. To determine the coordinating abilities of young athletes 10-11 years old during nine months of training in the chosen kind of sport. Skiing and cycling are extreme sports. But the material, technical, scientific and methodological support in these sports in Ukraine is at an insufficient level in comparison with Europe and America. Numerous studies have shown that the development of coordination abilities at a young age at the initial stage of long-term training must be combined with technical training. It is also noted that it is impossible at a young age to predict an athletic result in a chosen sport without taking into account the functional features and especially technical skill. At the present stage, there is no doubt that the high intensity of use in the training process of exercises that provide the maximum efficiency of specific exercises of a coordination orientation. At the same time, one-sided emphasis on technical training, especially at the initial stages of sports training, following the data of researchers, leads to limitation of motor actions. Therefore, our research is devoted to a relevant topic. The physical fitness testing of 10-11 year old sportsmen, carried out by us at the beginning and at the end, showed positive dynamics in all indicators. Statistical changes were determined in cyclists relative to skiers in pulling up on the crossbar, in raising the legs on the crossbar, in jumping over a log in 20 s, in long jump from a place (p <0,05). The training methodology introduced into the training process of young cyclists positively influenced the level of coordination abilities of young athletes of 10-11 years old. The growth rate turned out to be 8,4 % higher in walking on an 8-meter bench, by 7,0 % in the difference between a 15-meter run and a 15-meter slalom run, by 4,2 % in a 10-meter shuttle run 3 cubes each for cyclists relative to skiers.

scholarly journals Conceptual Scheme of Motor Asymmetry Control in Aerobic Cyclic Sports

2021 ◽  
pp. 214-225
Author(s):  
Svetlana S. Khudik ◽  
Aleksandr I. Chikurov ◽  
Andrey D. Burmistrov ◽  
Aleksandr L. Voinich
Keyword(s):  
Physical Exertion ◽  
The Body ◽  
Limiting Factor ◽  
Motor Asymmetry ◽  
Conceptual Scheme ◽  
Sports Performance ◽  
Training Process ◽  
Genetic Characteristics ◽  
Motor Actions ◽  
Lateral Phenotype

In this article, based on well-known literary data, the motor asymmetry of a person in the training process of aerobic cyclic sports is considered. The authors have analyzed the features of manifestation and consequences of the formation of motor asymmetry, and assessed its impact on sports performance. Motor asymmetry has been found to be based on the genetic characteristics of the organism, but the lateral phenotype may change during a multi-year training process under the influence of physical exertion. Excessive asymmetry has been shown to cause various pathologies and injuries. The results of the study indicate that in aerobic cyclic sports motor asymmetry can be both a factor contributing to the growth of sports performance and a limiting one, depending on what function this or that part of the body performs. Despite the repetitive cycle of motor actions, typical for cyclic sports, only in 3 out of the 8 considered functions performed by limbs or a certain part of the body, motor asymmetry was a limiting factor. This allowed the authors to predict a possible conceptual scheme of motor asymmetry control in aerobic cyclic sports

scholarly journals BODY IMAGE AND MENTAL REPRESENTATION IN TABLE TENNIS PLAYERS WHO DO VERSUS DO NOT USE A PROSTHESIS

2017 ◽  
Vol 11 (1) ◽  
pp. 22-30
Author(s):  
Damian Jeraj ◽  
Lisa Musculus ◽  
Babett H. Lobinger
Keyword(s):  
Body Image ◽  
Mental Representation ◽  
Mental Representations ◽  
Methodological Approach ◽  
The Body ◽  
Table Tennis ◽  
Tennis Players ◽  
Athletes With Disabilities ◽  
Tennis Serve ◽  
Similar Body

The prosthesis that athletes use should take over the function of the missing limb. Playing table tennis without constraints is one exemplary goal. The question arose whether table tennis players who used a prosthesis and players who did not show similar body image values and mental representation of movements. Five matched pairs of active table tennis players (n = 10) completed a body image questionnaire. Additionally, the mental representation of a forehand table tennis serve was assessed. Results revealed no significant differences between the two groups of athletes on mental representations. Furthermore, the integration of the prosthesis into the body image was considered satisfying by four out of the five athletes with prosthesis, the use of a prosthesis did not appear to affect athletes’ body image. Based on the research results it can be recommended that in technical and mental training sessions, one methodological approach be used for all athletes, regardless of whether they use a prosthesis. Finally, it is suggested to foster the integration of athletes who use a prosthesis into the established leagues in which athletes compete who do not use prosthesis. Key words: functional body image, mental structure, SDA-M, athletes with disabilities.

scholarly journals Differences in kinematic parameters between male and female hammer throw finalists of the World Championship in Daegu in 2011

2020 ◽  
Vol 24 (5) ◽  
pp. 255-263
Author(s):  
Ratko Pavlović
Keyword(s):  
Standard Deviation ◽  
Ejection Velocity ◽  
Kinematic Parameters ◽  
Training Process ◽  
Anatomical Structures ◽  
Male And Female ◽  
World Championship ◽  
The World ◽  
Technical Mastery ◽  
Biomechanical Parameters

Background and Study Aim. Hammer throwing is the most complex athletic throwing discipline with rotational trajectory and strong effect of several different forces that try to disable the projected throwing trajectory. Kinematic parameters are an important segment in the analysis of athletic disciplines, including hammer throw. They are an indicator of influence and often a difference between competitors of different or the same rank of the competition. The aim of the study was to determine the spatial and temporal differences of kinematic parameters between male and female elite hammers. Material and Methods. The study was conducted on sample of 16 Daegu World Championship finalists in 2011, to analyse differences in kinematic parameters between male and female throwers hammer. To obtain the required results, t-test for small independent samples was applied. Results. The data obtained in the study were given as Mean and Standard deviation. Statistically significant differences between male and female finalists were confirmed in the rate of ejection (t=3.684; p<0.004) and the speed of the fourth turn (t=4.396; p<0.002). The male finalists achieved an average ejection velocity of 27.91m/s and the female finalists 27.17m/s, with an average turn speed of 4.67m/s (male) and 4.03m/s (female). Conclusions. The research has shown that significant differences were made between male and female finalists in Daegu in 2011. The causes of differences can be found in length of training, different training process, technical mastery, competitor experience, morphological profile, motor and anatomical structures, movement technique and biomechanical parameters, which were not taken into the research.

Osteopathic support of sportsmen during the annual training process

2020 ◽  
pp. 37-43 ◽  
Author(s):  
R. A. Yakupov ◽  
G. I. Safiullina ◽  
A. A. Safiullina ◽  
E. R. Burganov
Keyword(s):  
Musculoskeletal Diseases ◽  
Muscle Tone ◽  
The Body ◽  
Training Process ◽  
Health Maintenance ◽  
Osteopathic Treatment ◽  
Leading Position ◽  
Myofascial Syndrome ◽  
Sports Activities ◽  
Timely Treatment

Introduction. Modern sports places high demands on the functional systems of the body at all stages of the training and competitive processes. High loads create signifi cant background for the occurrence of musculoskeletal diseases, among which the myofascial syndrome (MFS) holds the leading position. MFS negatively affects the functional readiness of the sportsman′s body and is a risk factor for injuries of the musculoskeletal system. In this regard, timely treatment of MFS is important. It creates the conditions for the improvement of sports achievements, for health maintenance and sports longevity. Treatment of patients with MFS should include methods that normalize trophism and muscle tone. Given the problem of doping, the use of non-drug methods, including osteopathy, is preferable. The goal of research — to develop a system of monitoring and osteopathic correction of myofascial disorders (MFD) and to introduce it into the practice of medical and biological support for sportsmen of different categories and levels during the annual training process.Materials and methods. 93 sportsmen (45 women and 48 men), mean age 22,1±1,1 years, representing diffe rent sports were examined. The essence of the proposed system is regular clinical and electroneurophysiological monitoring of the body condition and preventive correction of myofascial disorders in order to exclude their infl uence on the success of sports activities.Results. It was established that the proposed system of monitoring and osteopathic correction led to a signifi cant reduction in clinical and electroneurophysiological manifestations both in local and in extensive forms of myofascial disorders, which allowed to maintain the optimal functional readiness of sportsmen throughout the entire annual training cycle.Conclusion. The system of monitoring and correction of MFS with the use of osteopathic treatment can be one of the elements of medical and biological support for sportsmen during the annual training process.

scholarly journals Age-Related, Sport-Specific Adaptions of the Shoulder Girdle in Elite Adolescent Tennis Players

2014 ◽  
Vol 49 (5) ◽  
pp. 647-653 ◽  
Author(s):  
Ann M. Cools ◽  
Tanneke Palmans ◽  
Fredrik R. Johansson
Keyword(s):  
Muscle Strength ◽  
Shoulder Girdle ◽  
Vital Role ◽  
The Body ◽  
Injury Incidence ◽  
Shoulder Injury ◽  
Serratus Anterior ◽  
Cross Sectional ◽  
Tennis Players ◽  
Age Related

Context Tennis requires repetitive overhead movements that can lead to upper extremity injury. The scapula and the shoulder play a vital role in injury-free playing. Scapular dysfunction and glenohumeral changes in strength and range of motion (ROM) have been associated with shoulder injury in the overhead athlete. Objective To compare scapular position and strength and shoulder ROM and strength between Swedish elite tennis players of 3 age categories (&lt;14, 14–16, and &gt;16 years). Design Cross-sectional study. Setting Tennis training sports facilities. Patients or Other Participants Fifty-nine adolescent Swedish elite tennis players (ages 10–20 years) selected based on their national ranking. Main Outcome Measure(s) We used a clinical screening protocol with a digital inclinometer and a handheld dynamometer to measure scapular upward rotation at several angles of arm elevation, isometric scapular muscle strength, glenohumeral ROM, and isometric rotator cuff strength. Results Players older than 16 years showed less scapular upward rotation on the dominant side at 90° and 180° (P &lt; .05). Although all absolute scapular muscle strength values increased with age, there was no change in the body-weight–normalized strength of the middle (P = .9) and lower (P = .81) trapezius or serratus anterior (P = .17). Glenohumeral internal-rotation ROM and total ROM tended to decrease, but this finding was not statistically significant (P = .052 and P = .06, respectively). Whereas normalized internal-rotator strength increased from 14 to 16 years to older than 16 years (P = .009), normalized external-rotator and supraspinatus strength remained unchanged. Conclusions Age-related changes in shoulder and scapular strength and ROM were apparent in elite adolescent tennis players. Future authors should examine the association of these adaptations with performance data and injury incidence.

scholarly journals The Activity Profile of Young Tennis Athletes Playing on Clay and Hard Courts: Preliminary Data

2016 ◽  
Vol 50 (1) ◽  
pp. 211-218 ◽  
Author(s):  
Lucas Adriano Pereira ◽  
Victor Freitas ◽  
Felipe Arruda Moura ◽  
Marcelo Saldanha Aoki ◽  
Irineu Loturco ◽  
...  
Keyword(s):  
Physical Performance ◽  
Preliminary Data ◽  
High Intensity ◽  
The Body ◽  
Activity Profile ◽  
Red Clay ◽  
Tennis Players ◽  
Body Load ◽  
H 30 ◽  
Paired T Test

Abstract The aim of this study was to compare the kinematic characteristics of tennis matches between red clay and hard courts in young tennis players. Eight young tennis players performed two tennis matches on different court surfaces. The match activities were monitored using GPS units. The distance covered in different velocity ranges and the number of accelerations were analyzed. The paired t test and inference based on magnitudes were used to compare the match physical performance between groups. The total distance (24% of difference), high-intensity running distance (15 - 18 km/h) (30% of difference), the number of high-intensity activities (44% of difference), the body load (1% of difference), and accelerations >1.5 g (1.5-2 g and >2 g 7.8 and 8.1 % of difference, respectively) were significantly greater in clay court than hard court matches (p < 0.05). Matches played on the red clay court required players to cover more total and high-intensity running distances and engage in more high-intensity activities than the matches played on the hard court. Finally, on the clay court the body load and the number of accelerations performed (>1.5 g) were possibly higher than on the hard court.

Change in skeletal muscle index and its prognostic significance in conversion therapy for initially unresectable colorectal cancer.

2021 ◽  
Vol 39 (3_suppl) ◽  
pp. 56-56
Author(s):  
Hiroaki Nozawa ◽  
Shigenobu Emoto ◽  
Koji Murono ◽  
Yasutaka Shuno ◽  
Soichiro Ishihara
Keyword(s):  
Colorectal Cancer ◽  
Skeletal Muscle ◽  
Muscle Mass ◽  
Skeletal Muscles ◽  
Systemic Chemotherapy ◽  
Stage Iv ◽  
The Body ◽  
Pharmacological Intervention ◽  
Conversion Therapy ◽  
Skeletal Muscle Index

56 Background: Systemic chemotherapy can cause loss of skeletal muscle mass in colorectal cancer (CRC) patients in the neoadjuvant and palliative settings. However, it is largely unknown how the body composition is changed by chemotherapy rendering unresectable CRC to resectable disease or how it affects the prognosis. This study aimed at elucidating the effects of systemic chemotherapy on skeletal muscles and survival in stage IV CRC patients who underwent conversion therapy. Methods: We reviewed 98 stage IV CRC patients who received systemic chemotherapy in our hospital. According to the treatment setting, patients were divided into the ‘Conversion’, ‘Neoadjuvant chemotherapy (NAC)’, and ‘Palliation’ groups. The cross-sectional area of skeletal muscles at the third lumbar level and changes in the skeletal muscle index (SMI), defined as the area divided by height squared, during chemotherapy were compared among patient groups. The effects of these parameters on prognosis were analyzed in the Conversion group. Results: The mean SMI increased by 8.0% during chemotherapy in the Conversion group (n = 38), whereas it decreased by 6.2% in the NAC group (n = 18) and 3.7% in the Palliation group (n = 42, p < 0.0001). Moreover, patients with increased SMI during chemotherapy had a better overall survival (OS) than those whose SMI decreased in the Conversion group (p = 0.021). The increase in SMI was an independent predictor of favorable OS on multivariate analysis (hazard ratio: 0.26). Conclusions: Stage IV CRC patients who underwent conversion to resection often had an increased SMI. As such an increase in SMI further conveys a survival benefit in conversion therapy, it may be important to make efforts to preserve muscle mass by meticulous approaches, such as nutritional support, muscle exercise programs, and pharmacological intervention even during chemotherapy in patients with metastatic CRC.

Cinematographic and electromyographic analysis of vertical standing jump in the dog

1979 ◽  
Vol 83 (1) ◽  
pp. 271-282
Author(s):  
M. Tokuriki
Keyword(s):  
Skeletal Muscles ◽  
Lower Extremities ◽  
Axial Skeleton ◽  
The Body ◽  
Wire Electrode ◽  
Centre Of Gravity ◽  
Electrode Method ◽  
Electromyographic Analysis ◽  
Floating Phase

The electromyograms of 37 skeletal muscles were obtained using the bipolar wire electrode method in the vertical standing jump of a dog. Their electromyographic patterns were analyzed in conjunction with cinematographic films. Co-contraction of muscles of the extremities was observed during take-off and landing. Electromyograms also revealed that the forelimbs were accelerated against the body just after take-off and that the fore quarters transferred the centre of gravity of the body in a much more complicated movement than the hind quarters. In the floating phase, the muscles of the lower extremities had no activity, apart from some proximal ones. That the muscles of the four extremities exhibited their activity just before landing indicates that the activity may have been controlled by a central programme. In the vertical standing jump, the dog brings the centre of gravity of the body near to the kicking or landing paws by skillful movement of the axial skeleton. Cinematography revealed that, in the leaping gallop gait, the dog makes a similar movement of its axial skeleton.

Mediolateral somitic origin of ribs and dermis determined by quail-chick chimeras

Development ◽  
2000 ◽  
Vol 127 (21) ◽  
pp. 4611-4617 ◽  
Author(s):  
I. Olivera-Martinez ◽  
M. Coltey ◽  
D. Dhouailly ◽  
O. Pourquie
Keyword(s):  
Skeletal Muscles ◽  
Body Wall ◽  
Primitive Streak ◽  
Axial Skeleton ◽  
Lateral Compartment ◽  
The Body ◽  
The Other ◽  
Lateral Part ◽  
Respective Contribution ◽  
Epaxial Muscles

Somites are transient mesodermal structures giving rise to all skeletal muscles of the body, the axial skeleton and the dermis of the back. Somites arise from successive segmentation of the presomitic mesoderm (PSM). They appear first as epithelial spheres that rapidly differentiate into a ventral mesenchyme, the sclerotome, and a dorsal epithelial dermomyotome. The sclerotome gives rise to vertebrae and ribs while the dermomyotome is the source of all skeletal muscles and the dorsal dermis. Quail-chick fate mapping and diI-labeling experiments have demonstrated that the epithelial somite can be further subdivided into a medial and a lateral moiety. These two subdomains are derived from different regions of the primitive streak and give rise to different sets of muscles. The lateral somitic cells migrate to form the musculature of the limbs and body wall, known as the hypaxial muscles, while the medial somite gives rise to the vertebrae and the associated epaxial muscles. The respective contribution of the medial and lateral somitic compartments to the other somitic derivatives, namely the dermis and the ribs has not been addressed and therefore remains unknown. We have created quail-chick chimeras of either the medial or lateral part of the PSM to examine the origin of the dorsal dermis and the ribs. We demonstrate that the whole dorsal dermis and the proximal ribs exclusively originates from the medial somitic compartment, whereas the distal ribs derive from the lateral compartment.

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