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The Influence of Biomechanical Factors on Belle Piked Highly Executed Gymnastic Performance on the Parallel Bars
Arangala Witharanage Suraj Chandana
Issue:
Volume 10, Issue 3, September 2022
Pages:
40-45
Received:
10 May 2022
Accepted:
30 June 2022
Published:
12 July 2022
DOI:
10.11648/j.ajss.20221003.11
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Abstract: The purpose of this study was to identify the correct technique to perform highly executed long swing gymnastic movement: Belle Piked (BP). Two national Chinese gymnasts (58kg, 60.3kg) performed 4 repetitions of BP movement, on the middle of parallel bars with zero deduction. Reflective markers (14mm) and ten high-speed cameras (ViconT40S, 100Hz) were used to observe the time history of attached markers on the Humeral head and Cervical Vertebra (C7). The coordinates of the necessary markers were observed using ViconT40S digitizing software. Standard Lagrange dynamic equations were used to derive the dynamic equations of Arm. The average stiffness coefficient of the shoulder joints (KS,Avg = 31,670 N.m-1) was estimated through the model of the shoulder. The reaction on the Humeral head (RS,Avg = 196.14 N) under the bars (angular displacement of C.G is 180°) is significantly lower than the other places of the movement pattern. Also, the direction of acceleration of the Humeral head (-2.88 m.s-1) implied that the player moves the body upward with respect to the C7. The range of muscle torque around the shoulder joint is -10.8 N.m < τs < + 18.2 N.m. Though the angle of the head and neck segment with the vertical axis is nearly zero at the bottom of the bars, the gain of elastic energy from bars was optimized (122.75 J for 58 kg player). Therefore, optimum values of these biomechanical factors are influenced to promote BP movement on the parallel bars with zero execution errors.
Abstract: The purpose of this study was to identify the correct technique to perform highly executed long swing gymnastic movement: Belle Piked (BP). Two national Chinese gymnasts (58kg, 60.3kg) performed 4 repetitions of BP movement, on the middle of parallel bars with zero deduction. Reflective markers (14mm) and ten high-speed cameras (ViconT40S, 100Hz) w...
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Analysis of the Physical Performance and Decision-Making of Football Referees in Hot and Humid Environments
Mohamed Houssein Ali,
Pierre-Marie Lepretre,
Soubere Mahamoud Yonis,
Maryne Cozette,
Youssouf Ballah,
Said Ahmaidi
Issue:
Volume 10, Issue 3, September 2022
Pages:
46-51
Received:
24 May 2022
Accepted:
29 June 2022
Published:
12 July 2022
DOI:
10.11648/j.ajss.20221003.12
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Abstract: The aim of the present study was to assess the acclimated central referee’s activities during matches conducted under hot and humid conditions. The physical activity and number, the rightness or error of decisions taking was determined during Official matches of the 2018-2019 Djibouti’s Football Championship. All matches were filmed with a digital camera. The movements were quantified as previously described by Da Silva protocol walking (5.8km.h-1), backwards and agility movements (8.9 km.h-1), jogging (11.4 km.h-1), fast running (18.3km.h-1) sprint (25.2 km.h-1). Polar V800 was used to quantify the distance covered, LongoMatch® to count the number of decision-making and also Kinovea® free software to measure the distance between central referee position and the offence emplacement (Location). The referee’s group sample characteristic were: mean age of 29 ± 6.2 years, body mass of 66.3 ± 6.9 kg, stature of 1.76 ± 0.1m, body mass index of 21.6 ± 2.4 kg.m-² and a percentage of fat of 15.9 ± 3%. Results showed that central referees covered during a match an average distance of 10113 ± 820m. The patterns of total distances by acclimated Football referees in this study are lower with previous results observed under temperate conditions by other study. 122 ± 4.6 decisions per match have been made by referee. Compared to the first half, more decisions were taken in the second half (P = 0.037), with a significant decrease in decision making under-15m and an increase in decision making over 15m during the last 15min of the match (P = 0.008). Consequently, the distance separating the central referee position and the whistled action emplacement increased over time (P = 0.005) with qualities of decision. The number of decision-making was also comparable to the previous results observed during the Euro 2000 Football matches. In conclusion, acclimated referee’s physical performance shows lower physical performances in the heat comparable to referees physical performance observed in temperate zone.
Abstract: The aim of the present study was to assess the acclimated central referee’s activities during matches conducted under hot and humid conditions. The physical activity and number, the rightness or error of decisions taking was determined during Official matches of the 2018-2019 Djibouti’s Football Championship. All matches were filmed with a digital ...
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Proposal for a Motor Ability Development Model Based on Fujimmon’s Growth Curves
Issue:
Volume 10, Issue 3, September 2022
Pages:
52-59
Received:
23 June 2022
Accepted:
6 July 2022
Published:
12 July 2022
DOI:
10.11648/j.ajss.20221003.13
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Abstract: Scammon’s growth curves are often cited in discussions of motor ability development and training theory. However, Scammon’s theory of growth curves was proposed more than 90 years ago, and its scientific value is weak. Therefore the growth curves of Scammon was reexamined, and Fujimmon growth curves was newly proposed. If based on Fujimmon’s growth curves, a motor ability development model can be hypothesized as a mixed type model combining the general and neural types. To verify that hypothesis, author applied the wavelet interpolation model to the motor ability development process, analyzed the behavior of the velocity curves, and investigated whether the motor ability development pattern showed a curve pattern closer to the general type or neural type. As a result, it was shown that development patterns for things such as agility and running ability show curves that depend on the neural pattern, while development patterns for abilities requiring muscle strength and explosiveness show curves that depend on the general type. In girls, the pattern of motor ability development tended more strongly to depend on the neural type compared with boys. Consequently, from this study author was able to newly propose three types of curves: a pattern with a high level of dependence on the general type, a pattern with a high level of dependence on the neural type, and a standard development pattern of those two types. With the proposal of these three types of model curves, author may gain new perspectives on the utilization of sports training and the discovery of sports talent.
Abstract: Scammon’s growth curves are often cited in discussions of motor ability development and training theory. However, Scammon’s theory of growth curves was proposed more than 90 years ago, and its scientific value is weak. Therefore the growth curves of Scammon was reexamined, and Fujimmon growth curves was newly proposed. If based on Fujimmon’s growth...
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The Difference of Angles Between Down-The-Side Line Shot and Cross Shot of the Two-Handed Backhand Stroke in Tennis as a Basis for Skill Training
Hager Salah Abdou,
Ahmed Abdel Fatah Hassanien
Issue:
Volume 10, Issue 3, September 2022
Pages:
60-65
Received:
17 June 2022
Accepted:
8 July 2022
Published:
18 July 2022
DOI:
10.11648/j.ajss.20221003.14
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Abstract: The purpose of this study was to investigate the difference in angles between a Cross shot and Down-The-Side line shot stroke for the skill of the Tow-Handed backhand in beginning of back swing, end of back swing, ball impact, and end of follow through. There are 9 players in the Top -10 of Association of Tennis professional (ATP) are used two-handed backhand batting Technology, that is 90%. Two-handed backhand grips influence both the strength and the coordination used in the stroke. Sample of subjects Five experienced young boys’ tennis players from Sporting club in Alexandria, Egypt. They are participating in national championships. Biomechanics is an essential tool for understanding movement and the adjustments in the stroke of tennis. Methods we are using Simi 3D motion analysis V.9.0.6 Program of Kinematic analysis to data analysis. The results of Man-Whitney nonparametric test for comparing 2 independent groups. Results This study success to show differences in angles between a Cross shot and Down-The-Side line shot stroke for the skill of the Tow-Handed backhand. Conclusion Cross shot stroke for the skill of the Tow-Handed backhand need to more rotation in lower and upper body than Down-The-Side line shot stroke for the skill of the Tow-Handed backhand to hit the ball in cross court successfully. We may need more research to understand more of the differences between a Cross shot and Down-The-Side line shot stroke for the skill of the Tow-Handed backhand from other sides.
Abstract: The purpose of this study was to investigate the difference in angles between a Cross shot and Down-The-Side line shot stroke for the skill of the Tow-Handed backhand in beginning of back swing, end of back swing, ball impact, and end of follow through. There are 9 players in the Top -10 of Association of Tennis professional (ATP) are used two-hand...
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Effects of a High-Protein Ketogenic Diet on Strength Training Performance and Body Composition in Recreational Weight Lifters
Shivang Sharadkumar Patel
Issue:
Volume 10, Issue 3, September 2022
Pages:
66-83
Received:
31 July 2022
Accepted:
19 August 2022
Published:
31 August 2022
DOI:
10.11648/j.ajss.20221003.15
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Abstract: Weight Lifters often manipulate dietary protein to build muscles, and one dietary approach is a High-Protein Ketogenic Diet (HPKD). However, very little research has been conducted on the effects of a high-protein ketogenic diet on strength training performance and muscle building outcome goals. Therefore, the purpose of the present study is to investigate whether a high-protein ketogenic diet (HPKD) is an effective strategy to decrease fat mass (FM), and maintain lean body mass (LBM) without compromising strength training performance in recreational, weight lifters. In a parallel-arm, longitudinal, diet- and exercise-controlled design, 43 participants (mean ± SD age = 24.58 ± 9.26 years) exercised for 6 weeks while consuming either a high-protein ketogenic diet (HPKD) or a Normal Diet (ND). The HPKD intervention group (males, n = 13; females, n = 11) was instructed to consume a diet with 60% fat, 35% protein and 5% carbohydrates. Those in ND group (males, n = 10; females, n = 9) maintained a normal diet with 25% fat, 15% protein and 60% carbohydrates. The HPKD group significantly decreased body weight (mean ± SD, Weight: -1.55 ± 2.38 kg, p < 0.05), body fat percent (mean ± SD, %BF: -3.58 ± 0.85 kg, p < 0.05), and fat mass (mean ± SD, FM: -2.80 ± 0.87 kg, p < 0.05) compared to pre intervention measurements while significantly increased lean mass (mean± SD, LM: 1.25 ± 2.02 kg, p < 0.05), basal metabolic rate (mean ± SD, BMR: 76.76 ± 2.02 kcal/d, BMR: +4.44%, p < 0.000001), and strength (1RM) for all three lifts (bench press: 8.13 ± 4.85 kg, p < 0.05; back squat: 5.0 ± 2.95 kg, p < 0.05; deadlift: 8.13±7.04 kg, p < 0.05) between pre and post intervention in 6 weeks. However, there were no significant differences were observed (p > 0.05) in any variables of the HPKD group compared to ND group (Weight: p = 0.52, Body Fat Percentage: p = 0.62, Fat Mass: p = 0.58, Lean Mass: p = 0.63, BMR: p = 0.47, Back Squat: p = 0.29; Deadlift: p = 0.15; Bench Press: p = 0.18). Our data show that adhering to a HPKD combined with Strength Training for 6 weeks can lead to significant decreases in %BF, FM, and body weight, while significantly improving LM, BMR and overall strength performance in all three main lifts. This indicates a high-protein ketogenic diet can be an effective strategy to reduce body weight and fat mass without negatively affecting lean body mass, strength, or power performance.
Abstract: Weight Lifters often manipulate dietary protein to build muscles, and one dietary approach is a High-Protein Ketogenic Diet (HPKD). However, very little research has been conducted on the effects of a high-protein ketogenic diet on strength training performance and muscle building outcome goals. Therefore, the purpose of the present study is to inv...
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