scholarly journals Identifying a Connection Between Mobility Degree, Balance, Strength, and Tennis Serve: a Pilot Study

GYMNASIUM ◽  
2019 ◽  
Vol XIX (2) ◽  
pp. 130
Author(s):  
Rodica Prodan ◽  
Emilia Florina Grosu ◽  
Cornelia Popovici ◽  
Vlad Teodor Grosu
Keyword(s):  
Rotation Angle ◽  
External Rotation ◽  
Pearson Correlation ◽  
Lower Limbs ◽  
Pearson Correlation Coefficient ◽  
Reasonable Expectation ◽  
Tennis Players ◽  
Independent Variables ◽  
Tennis Serve ◽  
Individual Capacity

Tennis serve is the only hit that depends exclusively on the hitter. This aspect leads to the necessity of identification and understanding of the importance of all the elements. The hypothesis is that serve speed is predictable by force of upper and lower limbs. A group of 24 amateur young tennis players, (age of 14 ±2) was subjected to a series of mobility, balance, strength and serve speed testing. The Pearson correlation coefficient was used to identify connections between serve speed, considered as a dependent variable, and mobility, balance, and strength, as independent variables. The hip external rotation angle of the non-dominant arm, one-leg jumps, and one arm ball throws have shown strong positive associations with serve speed (p < 0.05). The anticipation of serve speed had an 81% variance of precision. A combination of body mobility and force may lead to the reasonable expectation the serve speed individual capacity.

scholarly journals Relationship Between Range of Motion, Strength, Motor Control, Power, and the Tennis Serve in Competitive-Level Tennis Players: A Pilot Study

2018 ◽  
Vol 10 (5) ◽  
pp. 462-467 ◽  
Author(s):  
Kenneth Palmer ◽  
Debi Jones ◽  
Christine Morgan ◽  
Giorgio Zeppieri
Keyword(s):  
Motor Control ◽  
Lower Extremity ◽  
Range Of Motion ◽  
Internal Rotation ◽  
External Rotation ◽  
Pearson Correlation ◽  
Tennis Players ◽  
Control Power ◽  
Tennis Serve ◽  
Shot Put

Background: The tennis serve is a complex skill requiring appropriate energy transfer to maximize serve speed. As the only independently powered shot in tennis, it is important to understand what characteristics contribute to a player’s serve. Hypothesis: Upper extremity and lower extremity power variables will be predictive of serve speed. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: A total of 42 competitive tennis players underwent range of motion, strength, motor control, power, and serve speed testing. Motion assessment was completed for shoulder external and internal rotation, trunk rotation, hip external and internal rotation, and ankle dorsiflexion. Strength was assessed for the rotator cuff, scapula, and hip musculature. Motor control was evaluated through upper and lower extremity Y-balance testing. Power assessments were made using broad jump, single-leg hop, and seated unilateral shot put testing. Pearson correlation was conducted to assess associations of skill, height, and tested variables to serve speed. Significant variables were used in a stepwise linear regression model, with serve speed as the dependent variable. Variables are listed in relation to the participant’s dominant arm. Results: Skill, height, contralateral hip external rotation range of motion, nondominant arm Y-balance anterolateral reach, bilateral single-leg hops, and seated unilateral shot put throws for both arms demonstrated significant positive correlations to serve speed ( P < 0.05). Serve speed was predicted with 84% variance through skill, height, contralateral hip external rotation range of motion, ipsilateral single-leg hop, and the seated unilateral shot put throws. Conclusion: The ability to generate increased serve speed is multifactorial. The combination of skill, height, hip motion, and upper and lower extremity power may determine serve speed. Clinical Relevance: The findings suggest that motion, motor control, and power testing should be evaluated when working with this population to improve serve speed.

Testing Influences on Human Understanding of Software

1977 ◽  
Vol 21 (2) ◽  
pp. 167-171 ◽  
Author(s):  
S. B. Sheppard ◽  
L. T. Love
Keyword(s):  
Experimental Design ◽  
Computer Program ◽  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Control Flow ◽  
Pearson Correlation Coefficient ◽  
Powerful Predictor ◽  
Independent Variables ◽  
Human Understanding ◽  
Data Points

Eight experienced programmers were each given three FORTRAN programs to memorize and reproduce functionally, without notes. Three levels of complexity of control flow and three levels of mnemonic variable names were independently manipulated. The experimental design was an incomplete split-plot factorial where each programmer was given one version of each program and all levels of the two primary independent variables. The participants correctly recalled significantly more statements when the complexity of control flow was reduced. Differences in recall for the three levels of mnemonic variable names were not significant. A further analysis compared the percent of statements correctly recalled to Halstead's E, a measure of the effort required to code a program. The Pearson correlation coefficient was −0.81, over the 24 data points; thus indicating that Halstead's E is a powerful predictor of one's ability to understand a computer program.

scholarly journals Does grip strength predict lower limb global strength in subjects with stroke?

2020 ◽  
Vol 33 ◽  
Author(s):  
Juliane Franco ◽  
Ludmylla Ferreira Quintino ◽  
Christina Danielli Coelho de Morais Faria
Keyword(s):  
Grip Strength ◽  
Lower Limb ◽  
Pearson Correlation ◽  
Chronic Phase ◽  
Lower Limbs ◽  
Pearson Correlation Coefficient ◽  
Subacute Phase ◽  
Different Populations ◽  
Global Strength ◽  
The Relationship

Abstract Introduction: Grip strength is an important clinical measure and has been used for several purposes in different populations, including those to predict the global strength of lower limbs (LL) and upper limbs. However, little is known about the association between grip strength and lower limb (LL) global strength in subjects with stroke. Objective: To investigate the relationship between grip strength and LL global strength in stroke with subjects at both subacute and chronic phases. Method: Measures of grip strength (handgrip dynamometer) and LL global strength (hand-held dynamometer) were obtained in 20 subjects in the subacute phase of the stroke and 18 in the chronic phase. Pearson correlation coefficient was used to investigate the correlation between grip strength and LL global strength (α = 0.05). Results: Subjects in the subacute phase showed a moderate statistically significant correlation between paretic grip strength and global strength of the non-paretic LL (r = 0.50; p < 0.05), but no correlation with the paretic LL was found (p = 0.25). The non-paretic grip strength showed no statistically significant correlation with global strength of the paretic LL (p = 0.93) and of the non-paretic LL (p = 0.64). In chronic subjects, no statistically significant correlation (0.50 ≤ p ≤ 0.97) was observed. Conclusion: Grip strength does not seem to be an adequate indicator to predict LL global strength of subjects with stroke. This conclusion is different from that obtained for other populations.

scholarly journals Sensors for Wheelchair Tennis: Measuring Trunk and Shoulder Biomechanics and Upper Extremity Vibration during Backhand Stroke

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6576
Author(s):  
Yan-Ying Ju ◽  
Wan-Ting Chu ◽  
Wann-Yun Shieh ◽  
Hsin-Yi Kathy Cheng
Keyword(s):  
Angular Velocity ◽  
Upper Extremity ◽  
External Rotation ◽  
Lower Limbs ◽  
Electromagnetic System ◽  
Tennis Players ◽  
Deceleration Phase ◽  
Shoulder Flexion ◽  
Acceleration And Deceleration ◽  
Shoulder Kinematics

This study was the first to compare the differences in trunk/shoulder kinematics and impact vibration of the upper extremity during backhand strokes in wheelchair tennis players and the able-bodied players relative to standing and sitting positions, adopting an electromagnetic system along with wearable tri-axial accelerometers upon target body segments. A total of 15 wheelchair tennis players and 15 able-bodied tennis players enrolled. Compared to players in standing positions, wheelchair players demonstrated significant larger forward trunk rotation in the pre-preparation, acceleration, and deceleration phase. Significant higher trunk angular velocity/acceleration and shoulder flexion/internal rotation angular velocity/acceleration were also found. When able-bodied players changed from standing to sitting positions, significant changes were observed in the degree of forward rotation of the trunk and shoulder external rotation. These indicated that when the functions of the lower limbs and trunk are lacking or cannot be used effectively, “biomechanical solutions” such as considerable reinforcing movements need to be made before the hitting movement. The differences between wheelchair tennis players and able-bodied players in sitting positions could represent the progress made as the wheelchair players evolve from novices to experts. Knowledge about how sport biomechanics change regarding specific disabilities can facilitate safe and inclusive participation in disability sports such as wheelchair tennis.

scholarly journals The Relationship Between Maximum Isometric Strength and Ball Velocity in the Tennis Serve

2016 ◽  
Vol 53 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Ernest Baiget ◽  
Francisco Corbi ◽  
Juan Pedro Fuentes ◽  
Jaime Fernández-Fernández
Keyword(s):  
Internal Rotation ◽  
External Rotation ◽  
Body Height ◽  
Isometric Strength ◽  
Tennis Players ◽  
Shoulder Flexion ◽  
Flexion Extension ◽  
Ball Velocity ◽  
Tennis Serve ◽  
The Relationship

AbstractThe aims of this study were to analyze the relationship between maximum isometric strength levels in different upper and lower limb joints and serve velocity in competitive tennis players as well as to develop a prediction model based on this information. Twelve male competitive tennis players (mean ± SD; age: 17.2 ± 1.0 years; body height: 180.1 ± 6.2 cm; body mass: 71.9 ± 5.6 kg) were tested using maximum isometric strength levels (i.e., wrist, elbow and shoulder flexion and extension; leg and back extension; shoulder external and internal rotation). Serve velocity was measured using a radar gun. Results showed a strong positive relationship between serve velocity and shoulder internal rotation (r = 0.67; p < 0.05). Low to moderate correlations were also found between serve velocity and wrist, elbow and shoulder flexion – extension, leg and back extension and shoulder external rotation (r = 0.36 – 0.53; p = 0.377 – 0.054). Bivariate and multivariate models for predicting serve velocity were developed, with shoulder flexion and internal rotation explaining 55% of the variance in serve velocity (r = 0.74; p < 0.001). The maximum isometric strength level in shoulder internal rotation was strongly related to serve velocity, and a large part of the variability in serve velocity was explained by the maximum isometric strength levels in shoulder internal rotation and shoulder flexion.

Pengaruh Kotbah, Musik Gereja Dan Fasilitas Gereja Terhadap Tingkat Kehadiran Jemaat

2016 ◽  
Vol 1 (1) ◽  
pp. 1-15
Author(s):  
Frederich Oscar Lontoh
Keyword(s):  
Regression Analysis ◽  
Multiple Regression Analysis ◽  
Church Music ◽  
Pearson Correlation ◽  
Descriptive Analysis ◽  
Target Population ◽  
The Other ◽  
Pearson Correlation Coefficient ◽  
Christian Church ◽  
The City

This research is titled " The influence of sermon, church music and church facilities on the level of attendance”. The purpose of research is to identify and analyze whether sermon, church music and church facilities have influence on the the level of attendance. The target population in this study is a Christian church members who live in the city of Surabaya.. Sample required is equal to 47 respondents. Through sampling stratified Random techniques.These influence was measured using Pearson correlation coefficient and multiple regression analysis, t-test and analysis of variance. Descriptive  analysis  were taken to analyze the level of attendance according to demographic groups.The hypothesis in this study are the sermon, church music and church facilities have positive and significant on the level of attendance. The results showed that collectively, there are positive and significant correlation among the sermon, church music and church facilities on the level of attendance  96,2%. It means that 96,2 % of level of attendance influenced by sermon, church music and church facilities and the other 28,9% by others. All of the variable partially have significant correlation to level of attendance.

Relationship between Invasive and Non-Invasive Hemodynamic Measures in Experimental Pulmonary Hypertension

2020 ◽  
Vol 16 (1) ◽  
pp. 47-53
Author(s):  
Vicente Benavides-Córdoba ◽  
Mauricio Palacios Gómez
Keyword(s):  
Heart Rate ◽  
Pulmonary Hypertension ◽  
Ejection Fraction ◽  
Right Ventricle ◽  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Systolic Pressure ◽  
Control Group ◽  
Pearson Correlation Coefficient ◽  
Non Invasive

Introduction: Animal models have been used to understand the pathophysiology of pulmonary hypertension, to describe the mechanisms of action and to evaluate promising active ingredients. The monocrotaline-induced pulmonary hypertension model is the most used animal model. In this model, invasive and non-invasive hemodynamic variables that resemble human measurements have been used. Aim: To define if non-invasive variables can predict hemodynamic measures in the monocrotaline-induced pulmonary hypertension model. Materials and Methods: Twenty 6-week old male Wistar rats weighing between 250-300g from the bioterium of the Universidad del Valle (Cali - Colombia) were used in order to establish that the relationships between invasive and non-invasive variables are sustained in different conditions (healthy, hypertrophy and treated). The animals were organized into three groups, a control group who was given 0.9% saline solution subcutaneously (sc), a group with pulmonary hypertension induced with a single subcutaneous dose of Monocrotaline 30 mg/kg, and a group with pulmonary hypertension with 30 mg/kg of monocrotaline treated with Sildenafil. Right ventricle ejection fraction, heart rate, right ventricle systolic pressure and the extent of hypertrophy were measured. The functional relation between any two variables was evaluated by the Pearson correlation coefficient. Results: It was found that all correlations were statistically significant (p <0.01). The strongest correlation was the inverse one between the RVEF and the Fulton index (r = -0.82). The Fulton index also had a strong correlation with the RVSP (r = 0.79). The Pearson correlation coefficient between the RVEF and the RVSP was -0.81, meaning that the higher the systolic pressure in the right ventricle, the lower the ejection fraction value. Heart rate was significantly correlated to the other three variables studied, although with relatively low correlation. Conclusion: The correlations obtained in this study indicate that the parameters evaluated in the research related to experimental pulmonary hypertension correlate adequately and that the measurements that are currently made are adequate and consistent with each other, that is, they have good predictive capacity.

Resilience and Support Networks for University Students with Disabilities

2018 ◽  
Vol 5 (2) ◽  
pp. 164
Author(s):  
María Leonila García Cedeño ◽  
Anicia Katherine Tarazona Meza ◽  
Robert Gonzalo Cedeño Mejía
Keyword(s):  
Social Networks ◽  
University Students ◽  
Students With Disabilities ◽  
Pearson Correlation ◽  
Support Networks ◽  
Pearson Correlation Coefficient ◽  
Structured Interviews ◽  
Disabled Students ◽  
The Social ◽  
Student Resilience

Resilience is a phenomenon that can be studied in catastrophic situations but also in everyday matters such as disability, this being an alternative way of working in the environment that requires the adaptation of the social networks that contain and support people with this condition. The research was conducted at the Technical University of Manabí applied to the population of students with disabilities. The paper presents an analysis of support networks and their relationship with student resilience. The results related to the application of the Saavedra-Villalta test are shown, which allowed to correlate the level of resilience of the sample studied with the support networks. An analysis linked to the interpretation of the Pearson correlation coefficient is presented. The result obtained is presented by applying semi-structured interviews to a sample of 48 disabled students.

scholarly journals Gender Differences in Kinematic Analysis of the Lower Limbs during the Chasse Step in Table Tennis Athletes

Healthcare ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 703
Author(s):  
Xiaoyi Yang ◽  
Yuqi He ◽  
Shirui Shao ◽  
Julien S. Baker ◽  
Bíró István ◽  
...  
Keyword(s):  
Female Athletes ◽  
External Rotation ◽  
Rotational Velocity ◽  
Knee Extension ◽  
Lower Limbs ◽  
Table Tennis ◽  
Male Athletes ◽  
Analysis System ◽  
Hip Flexion ◽  
Hip Internal Rotation

The chasse step is one of the most important footwork maneuvers used in table tennis. The purpose of this study was to investigate the lower limb kinematic differences of table tennis athletes of different genders when using the chasse step. The 3D VICON motion analysis system was used to capture related kinematics data. The main finding of this study was that the step times for male athletes (MA) were shorter in the backward phase (BP) and significantly longer in the forward phase (FP) than for female athletes (FA) during the chasse step. Compared with FA, knee external rotation for MA was larger during the BP. MA showed a smaller knee flexion range of motion (ROM) in the BP and larger knee extension ROM in the FP. Moreover, hip flexion and adduction for MA were significantly greater than for FA. In the FP, the internal rotational velocity of the hip joint was significantly greater. MA showed larger hip internal rotation ROM in the FP but smaller hip external rotation ROM in the BP. The differences between genders can help coaches personalize their training programs and improve the performance of both male and female table tennis athletes.

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