Bryan Heiderscheit
Professor, Department of Orthopedics and Rehabilitation, Department of Biomedical Engineering, Director, UW Runners' Clinic, Director, Badger Athletic Performance Research, Co-director, UW Neuromuscular Biomechanics Lab, University of Wisconsin-Madison, Madison, WI, USA.
-
Hamstrings are most susceptible to injury during the early stance phase of sprinting
(13th October, Barcelona)
6th MuscleTech Network Workshop
Neuromuscular plasticity in quadriceps functions in response to trainingMuscleTech Network
Neuromuscular plasticity in quadriceps functions in response to training and how this might affect sprinting ability and kicking performance
Per Aagaard
8th MuscleTech Network Workshop
Biomechanics is the study of mechanics in living beings, specifically analyzing forces and motion in the human body. It is divided into kinetics, which studies forces producing motion, and kinematics, which describes motion. Biomechanics is studied to improve health, performance, and understand complex movements. It has various applications in sports, medical devices, rehabilitation, and more. The field has grown significantly over time from early scientists like Aristotle and Da Vinci applying mechanics to the body. Modern biomechanics utilizes fields like computational modeling, simulation, and motion analysis.
This study examined muscle activation patterns in the lower extremities during different squat techniques. 28 healthy subjects performed squats with neutral alignment (control), intentional frontal plane malalignment (medial knee displacement), and sagittal plane malalignment (anterior knee displacement). Electromyography was used to measure muscle activation in the quadriceps, hamstrings, and gastrocnemius. Results showed altered muscle activation patterns during the malaligned squats, with decreased quadriceps activation during medial knee displacement and changes in quadriceps and hamstring activation timing during anterior knee displacement compared to the control squat. The study provides information on how muscle activation changes with different squat alignments.
Bryan Heiderscheit
Professor, Department of Orthopedics and Rehabilitation, Department of Biomedical Engineering, Director, UW Runners' Clinic, Director, Badger Athletic Performance Research, Co-director, UW Neuromuscular Biomechanics Lab, University of Wisconsin-Madison, Madison, WI, USA.
-
Hamstrings are most susceptible to injury during the early stance phase of sprinting
(13th October, Barcelona)
6th MuscleTech Network Workshop
Neuromuscular plasticity in quadriceps functions in response to trainingMuscleTech Network
Neuromuscular plasticity in quadriceps functions in response to training and how this might affect sprinting ability and kicking performance
Per Aagaard
8th MuscleTech Network Workshop
Biomechanics is the study of mechanics in living beings, specifically analyzing forces and motion in the human body. It is divided into kinetics, which studies forces producing motion, and kinematics, which describes motion. Biomechanics is studied to improve health, performance, and understand complex movements. It has various applications in sports, medical devices, rehabilitation, and more. The field has grown significantly over time from early scientists like Aristotle and Da Vinci applying mechanics to the body. Modern biomechanics utilizes fields like computational modeling, simulation, and motion analysis.
This study examined muscle activation patterns in the lower extremities during different squat techniques. 28 healthy subjects performed squats with neutral alignment (control), intentional frontal plane malalignment (medial knee displacement), and sagittal plane malalignment (anterior knee displacement). Electromyography was used to measure muscle activation in the quadriceps, hamstrings, and gastrocnemius. Results showed altered muscle activation patterns during the malaligned squats, with decreased quadriceps activation during medial knee displacement and changes in quadriceps and hamstring activation timing during anterior knee displacement compared to the control squat. The study provides information on how muscle activation changes with different squat alignments.
11.[6 12]assessing the relationship of kinematics with dribbling performance ...Alexander Decker
The document assessed the relationship between kinematics and dribbling performance in basketball at different phases. Twenty male basketball players aged 18-28 participated. Motion capture data of high dribbles were collected and correlations with performance scores were calculated. Results showed insignificant relationships between dribbling performance and angles of joints like the ankle, knee, hip, shoulder, elbow and wrist at both the preparation and execution phases of high dribbles. This suggests that joint angles may not be primary determinants of high dribble performance in basketball.
This study aims to define gait for shoulder-produced locomotion using the double-poling technique from sledge hockey. A solid-static prototype mimicking the average male torso was used to determine baseline measures during the preparation phase. The prototype's trajectory and reaction forces supported that preparation initiation should begin slightly below the horizon to produce the greatest force. Results from sledge hockey players and able-bodied controls will be used to illustrate the complete seated gait cycle, including phases for static-start, start cycle, contact, and recovery. This evidence could improve training and rehabilitation for people who use their shoulders for mobility.
This document provides an introduction to sports biomechanics. It defines biomechanics as the application of mechanical principles and laws to living organisms, and sports biomechanics as the application of these principles specifically to improve athletic performance. It outlines the branches of mechanics including kinetics, which deals with the causes of motion, and kinematics, which describes motion. Kinetics and kinematics each have static and dynamic components depending on whether the body is at rest or in motion. The goals of sports biomechanics are then listed as performance improvement, technique improvement, movement quality improvement, equipment improvement, injury prevention and rehabilitation.
This document discusses the rehabilitation process for quadriceps muscle injuries from initial injury through return to play. It begins by covering injury classification and the muscle architecture of the quadriceps. It then discusses muscle mechanics in running and kicking sports. Rehabilitation stages are outlined from early isometric exercises to advanced functional training mimicking sports movements. A case study is presented of an athlete who suffered multiple quadriceps injuries and underwent a rehabilitation process focused on hypertrophy, tendon elasticity and returning to high intensity running.
This document discusses core stability, core strength, and their relationship to athletic performance. It begins by defining key terms like performance, core stability, and core strength. It then explores the functional anatomy of the core and different types of core training. The document reviews evidence that core training provides benefits in rehabilitation by reducing lower back injuries, but evidence of performance enhancement in sports is less clear. Specifically, some studies found improvements in core stability and strength from training but ambiguous results on actual sports performance. The relationship between core stability, functional movement, and different performance tests is also examined but results suggest only weak to moderate correlations. While core and functional training are important for injury prevention, the evidence does not strongly support them as the primary focus for performance
Apply pressure to cuff to flatten lumbar curve
Client attempts to maintain neutral spine by contracting TA
Assess ability to maintain neutral spine with increasing pressure
Assess symmetry of contraction
Poor control = inability to maintain neutral or asymmetric contraction
6/19/2012 Ratankhuman M.P.T. (Ortho & Sports) 33
Abdominal Neuromuscular Control Test
Supine with hips & knees in 90
Pressure cuff placed under lum
This study investigated the preparation phase of the seated double poling cycle in sledge hockey through biomechanical analysis. A solid-static prototype representing an adult male was used with motion capture and force plates to measure kinematics and kinetics. Results showed peak impact forces occurred before 5 milliseconds post contact. Forces were greatest when preparation began slightly below the horizon. Data provides baseline measures to understand preparation phase importance and insights to improve sledge hockey performance and shoulder joint health.
Return to play in rectus femoris muscle injuries. Our experience with profess...MuscleTech Network
This document outlines a 4-step in-field return-to-play process for professional football players recovering from rectus femoris muscle injuries. The 4 steps progress from running circuits in dry sand, to circuits with a ball in dry sand, to uphill/downhill running, and finally specific football skills circuits. Each step aims to gradually increase difficulty, coordination, strength and sport-specific movements while monitoring pain and GPS data. The process is tailored to each player and aims to return them to full training and play in an optimal way according to their symptoms and injury severity.
Bilateral and unilateral vertical ground reaction forcesFernando Farias
The purposes of this study were to assess unilateral and bilateral vertical jump performance
characteristics, and to compare the vertical ground reaction force characteristics of the impulse and landing
phase of a vertical jump between the dominant and non-dominant leg in soccer players.
This document describes a biomechanical analysis of a lower limb strengthening device consisting of a harness connecting tension bands from the hips to the ankles. The analysis found that using the device increases muscle forces in the legs while improving load distribution across the knee joint. It also does not significantly increase forces on knee cartilage surfaces. The device thus has potential benefits for knee rehabilitation by strengthening muscles and joints in a balanced manner without excessive stress on cartilage.
Biomechanics is the study of mechanics as they relate to living organisms, especially to human movement and sports activities. Biomechanists use tools like video analysis, force platforms, and wind tunnels to analyze human performance, the causes of injuries, and ways to optimize sports equipment and techniques. The goals of biomechanics are to improve sports performance, prevent injuries, design better equipment, and develop training methods to transfer skills from practice to competition.
Maximal sprinting speed of elite soccer playersFernando Farias
Current findings might help individuals involved within the physical preparation of players (e.g. technical coaches, fitness coaches, and sport science staff) when developing training programs and training sessions in line with the playing positions, and with the levels of high speed running targeted to reach during specific training drills like sided-games.
Indeed, the closer to match-play situations regarding the rules with goals, goalkeepers, the larger pitch sizes and greater number of players involved, the higher sprinting speed running players would reach during sided-games. However, coaches are advised to add specific speed drills to sided-games in order to elicit a stimulus of high-speed running high enough to prepare players for competition.
This chapter discusses biomechanics and its importance in sports. It covers Newton's laws of motion and how forces like centripetal and centrifugal impact sports. The chapter also examines levers, equilibrium, center of gravity, and how understanding these concepts can help improve athletic performance and prevent injuries.
The four hamstrings muscles are: the biceps femoris (long head), the biceps
femoris (short head), the semitendinosus, and the semimembranosus. The
two biceps femoris muscles are located on the lateral part of the thigh.
The semitendinosus and the semimembranosus are located on the medial
part of the thigh.
This document discusses core stability training. It defines core stability as controlling the trunk over the pelvis and legs to allow force production and transfer. A stable core is important for injury prevention, performance, and linking the kinetic chain. The core has three systems - local stabilizers for stiffness, global stabilizers to link the pelvis and spine, and global mobilizers for gross movement. The document provides examples of exercises for each system and notes that programs should train the whole body dynamically while grooving motion patterns.
Biomechanics is the study of how forces affect living organisms during movement. It uses concepts from physics like mechanics, kinematics, and kinetics to understand human motion. Biomechanists study biomechanics to improve athletic performance and prevent injuries by understanding how forces impact the body during different activities. They analyze both the description of movement through kinematics and the causes of motion through kinetics.
Per Hölmich
Head of Aspetar Sports Groin Pain Center, Aspetar, Orthopaedic and Sports Medicine Hospital, Doha, Qatar & Associate Professor, Sports Orthopedic Research, Center - Copenhagen (SORC-C), Arthoscopic Center Amager, Copenhagen University Hospital, Denmark.
-
Nordic Hamstring for prevention in football - what did we learn?
(6th MuscleTech Network Workshop)
13th and 14th OCtober, 2014
Three dimensional biomechanical analysis of the drag in penalty corner drag f...Alexander Decker
This document analyzes the biomechanics of the penalty corner drag flick in field hockey through 3D motion analysis. It studied four specialized male drag flickers from two universities. Video analysis captured joint angles, velocities and accelerations during the drag flick. Statistical analysis found several kinematic variables differed significantly between the universities, including drag distance, shoulder and pelvis linear velocities, and angular velocities and accelerations of various joints. This suggests differences in drag flick technique influence accuracy. The study aimed to provide biomechanical information to help coaches and players enhance drag flick performance.
This study investigated the effect of knee joint angle on plantar flexor performance in resistance-trained and untrained men. Seventeen participants performed plantar flexion contractions at 90 degrees of knee flexion and 10 degrees of extension while torque was measured. There were no significant differences found in torque or rate of torque development between the knee positions or between the trained and untrained groups. The calibration process of the new dynamometer was found to be reliable.
1) The study examined the role of rotational power and mobility on cricket ball throwing velocity. It assessed rotational mobility, power outputs, and throwing velocities of professional and under-19 cricketers.
2) Participants were divided into fast and slow throwing groups based on cricket ball velocity. The fast throwers had significantly greater force, work, and throwing velocities compared to slow throwers.
3) However, slow throwers showed significantly greater range of motion in the thoracic and hip regions. The study concluded that greater proximal mobility may not increase throwing velocity, as reduced mobility can aid in transferring momentum from the lower body during explosive tasks like throwing.
11.[6 12]assessing the relationship of kinematics with dribbling performance ...Alexander Decker
The document assessed the relationship between kinematics and dribbling performance in basketball at different phases. Twenty male basketball players aged 18-28 participated. Motion capture data of high dribbles were collected and correlations with performance scores were calculated. Results showed insignificant relationships between dribbling performance and angles of joints like the ankle, knee, hip, shoulder, elbow and wrist at both the preparation and execution phases of high dribbles. This suggests that joint angles may not be primary determinants of high dribble performance in basketball.
This study aims to define gait for shoulder-produced locomotion using the double-poling technique from sledge hockey. A solid-static prototype mimicking the average male torso was used to determine baseline measures during the preparation phase. The prototype's trajectory and reaction forces supported that preparation initiation should begin slightly below the horizon to produce the greatest force. Results from sledge hockey players and able-bodied controls will be used to illustrate the complete seated gait cycle, including phases for static-start, start cycle, contact, and recovery. This evidence could improve training and rehabilitation for people who use their shoulders for mobility.
This document provides an introduction to sports biomechanics. It defines biomechanics as the application of mechanical principles and laws to living organisms, and sports biomechanics as the application of these principles specifically to improve athletic performance. It outlines the branches of mechanics including kinetics, which deals with the causes of motion, and kinematics, which describes motion. Kinetics and kinematics each have static and dynamic components depending on whether the body is at rest or in motion. The goals of sports biomechanics are then listed as performance improvement, technique improvement, movement quality improvement, equipment improvement, injury prevention and rehabilitation.
This document discusses the rehabilitation process for quadriceps muscle injuries from initial injury through return to play. It begins by covering injury classification and the muscle architecture of the quadriceps. It then discusses muscle mechanics in running and kicking sports. Rehabilitation stages are outlined from early isometric exercises to advanced functional training mimicking sports movements. A case study is presented of an athlete who suffered multiple quadriceps injuries and underwent a rehabilitation process focused on hypertrophy, tendon elasticity and returning to high intensity running.
This document discusses core stability, core strength, and their relationship to athletic performance. It begins by defining key terms like performance, core stability, and core strength. It then explores the functional anatomy of the core and different types of core training. The document reviews evidence that core training provides benefits in rehabilitation by reducing lower back injuries, but evidence of performance enhancement in sports is less clear. Specifically, some studies found improvements in core stability and strength from training but ambiguous results on actual sports performance. The relationship between core stability, functional movement, and different performance tests is also examined but results suggest only weak to moderate correlations. While core and functional training are important for injury prevention, the evidence does not strongly support them as the primary focus for performance
Apply pressure to cuff to flatten lumbar curve
Client attempts to maintain neutral spine by contracting TA
Assess ability to maintain neutral spine with increasing pressure
Assess symmetry of contraction
Poor control = inability to maintain neutral or asymmetric contraction
6/19/2012 Ratankhuman M.P.T. (Ortho & Sports) 33
Abdominal Neuromuscular Control Test
Supine with hips & knees in 90
Pressure cuff placed under lum
This study investigated the preparation phase of the seated double poling cycle in sledge hockey through biomechanical analysis. A solid-static prototype representing an adult male was used with motion capture and force plates to measure kinematics and kinetics. Results showed peak impact forces occurred before 5 milliseconds post contact. Forces were greatest when preparation began slightly below the horizon. Data provides baseline measures to understand preparation phase importance and insights to improve sledge hockey performance and shoulder joint health.
Return to play in rectus femoris muscle injuries. Our experience with profess...MuscleTech Network
This document outlines a 4-step in-field return-to-play process for professional football players recovering from rectus femoris muscle injuries. The 4 steps progress from running circuits in dry sand, to circuits with a ball in dry sand, to uphill/downhill running, and finally specific football skills circuits. Each step aims to gradually increase difficulty, coordination, strength and sport-specific movements while monitoring pain and GPS data. The process is tailored to each player and aims to return them to full training and play in an optimal way according to their symptoms and injury severity.
Bilateral and unilateral vertical ground reaction forcesFernando Farias
The purposes of this study were to assess unilateral and bilateral vertical jump performance
characteristics, and to compare the vertical ground reaction force characteristics of the impulse and landing
phase of a vertical jump between the dominant and non-dominant leg in soccer players.
This document describes a biomechanical analysis of a lower limb strengthening device consisting of a harness connecting tension bands from the hips to the ankles. The analysis found that using the device increases muscle forces in the legs while improving load distribution across the knee joint. It also does not significantly increase forces on knee cartilage surfaces. The device thus has potential benefits for knee rehabilitation by strengthening muscles and joints in a balanced manner without excessive stress on cartilage.
Biomechanics is the study of mechanics as they relate to living organisms, especially to human movement and sports activities. Biomechanists use tools like video analysis, force platforms, and wind tunnels to analyze human performance, the causes of injuries, and ways to optimize sports equipment and techniques. The goals of biomechanics are to improve sports performance, prevent injuries, design better equipment, and develop training methods to transfer skills from practice to competition.
Maximal sprinting speed of elite soccer playersFernando Farias
Current findings might help individuals involved within the physical preparation of players (e.g. technical coaches, fitness coaches, and sport science staff) when developing training programs and training sessions in line with the playing positions, and with the levels of high speed running targeted to reach during specific training drills like sided-games.
Indeed, the closer to match-play situations regarding the rules with goals, goalkeepers, the larger pitch sizes and greater number of players involved, the higher sprinting speed running players would reach during sided-games. However, coaches are advised to add specific speed drills to sided-games in order to elicit a stimulus of high-speed running high enough to prepare players for competition.
This chapter discusses biomechanics and its importance in sports. It covers Newton's laws of motion and how forces like centripetal and centrifugal impact sports. The chapter also examines levers, equilibrium, center of gravity, and how understanding these concepts can help improve athletic performance and prevent injuries.
The four hamstrings muscles are: the biceps femoris (long head), the biceps
femoris (short head), the semitendinosus, and the semimembranosus. The
two biceps femoris muscles are located on the lateral part of the thigh.
The semitendinosus and the semimembranosus are located on the medial
part of the thigh.
This document discusses core stability training. It defines core stability as controlling the trunk over the pelvis and legs to allow force production and transfer. A stable core is important for injury prevention, performance, and linking the kinetic chain. The core has three systems - local stabilizers for stiffness, global stabilizers to link the pelvis and spine, and global mobilizers for gross movement. The document provides examples of exercises for each system and notes that programs should train the whole body dynamically while grooving motion patterns.
Biomechanics is the study of how forces affect living organisms during movement. It uses concepts from physics like mechanics, kinematics, and kinetics to understand human motion. Biomechanists study biomechanics to improve athletic performance and prevent injuries by understanding how forces impact the body during different activities. They analyze both the description of movement through kinematics and the causes of motion through kinetics.
Per Hölmich
Head of Aspetar Sports Groin Pain Center, Aspetar, Orthopaedic and Sports Medicine Hospital, Doha, Qatar & Associate Professor, Sports Orthopedic Research, Center - Copenhagen (SORC-C), Arthoscopic Center Amager, Copenhagen University Hospital, Denmark.
-
Nordic Hamstring for prevention in football - what did we learn?
(6th MuscleTech Network Workshop)
13th and 14th OCtober, 2014
Three dimensional biomechanical analysis of the drag in penalty corner drag f...Alexander Decker
This document analyzes the biomechanics of the penalty corner drag flick in field hockey through 3D motion analysis. It studied four specialized male drag flickers from two universities. Video analysis captured joint angles, velocities and accelerations during the drag flick. Statistical analysis found several kinematic variables differed significantly between the universities, including drag distance, shoulder and pelvis linear velocities, and angular velocities and accelerations of various joints. This suggests differences in drag flick technique influence accuracy. The study aimed to provide biomechanical information to help coaches and players enhance drag flick performance.
This study investigated the effect of knee joint angle on plantar flexor performance in resistance-trained and untrained men. Seventeen participants performed plantar flexion contractions at 90 degrees of knee flexion and 10 degrees of extension while torque was measured. There were no significant differences found in torque or rate of torque development between the knee positions or between the trained and untrained groups. The calibration process of the new dynamometer was found to be reliable.
1) The study examined the role of rotational power and mobility on cricket ball throwing velocity. It assessed rotational mobility, power outputs, and throwing velocities of professional and under-19 cricketers.
2) Participants were divided into fast and slow throwing groups based on cricket ball velocity. The fast throwers had significantly greater force, work, and throwing velocities compared to slow throwers.
3) However, slow throwers showed significantly greater range of motion in the thoracic and hip regions. The study concluded that greater proximal mobility may not increase throwing velocity, as reduced mobility can aid in transferring momentum from the lower body during explosive tasks like throwing.
Investigation of Relationship of Strength and Size of Different Body Parts to...IOSR Journals
This study investigated the relationship between strength, body size, and the velocity of volleyball serves and spikes. 30 male university volleyball players were measured for arm strength, grip strength, leg strength, back strength, arm length, hand length, leg length, foot length, and upper body length. Their serve and spike velocities were also recorded. Correlation analyses found significant relationships between serve velocity and arm strength, grip strength, leg strength, back strength, arm length, hand length, leg length, and upper body length. Significant relationships were also found between spike velocity and the same strength and body size measures. A multiple correlation analysis found that arm strength, arm length, and leg strength combined to highly correlate with serve velocity. Overall, the study
Kinematic factors of off speed and power spike techniques in volleyballAlexander Decker
The document summarizes a study that compared the kinematic factors of power and off-speed spike techniques in volleyball. The study found:
1) There were no significant differences in shoulder, elbow, wrist, or body inclination angles between the two spike techniques.
2) Pre-impact arm swing speed and post-impact ball speed also did not significantly differ between techniques.
3) The techniques of elite junior volleyball players for the power and off-speed spikes appear to be highly individualized based on the kinematic results.
11.javelin throwing technique a biomechanical studyAlexander Decker
This document is a research paper that analyzes the biomechanics of javelin throwing technique. It describes a study that filmed 6 javelin throwers from Aligarh Muslim University in India using high-speed cameras. The study found a significant positive correlation between throwing distance and initial javelin velocity at release. It found insignificant correlations between distance and other release parameters like angle, height, etc. The results suggest throwers should achieve high acceleration during their run-up and carry the javelin at optimal angles to maximize distance.
Javelin throwing technique a biomechanical studyAlexander Decker
This study analyzed the biomechanics of the javelin throwing technique through high-speed video analysis of 6 athletes. The study found:
1) A significant positive correlation between throwing distance and initial javelin velocity at release.
2) Insignificant correlations between throwing distance and release angle, attitude angle, attack angle, and release height.
3) Positive significant correlations between throwing distance and approach run velocity, pull distance, and forward trunk rotation angle.
The results suggest the most important factor for distance is high initial velocity, which is influenced by fast approach, leg thrust, and optimal carry angle during the last strides.
11.javelin throwing technique a biomechanical studyAlexander Decker
This document is a research paper that analyzes the biomechanics of javelin throwing technique. It describes a study that filmed 6 javelin throwers from Aligarh Muslim University in India using high-speed cameras. The study found a significant positive correlation between throwing distance and initial javelin velocity at release. It found insignificant correlations between distance and other release parameters like angle, height, etc. The results suggest throwers should achieve high acceleration during their run-up and carry the javelin at optimal angles to maximize distance.
This document summarizes and analyzes several research studies on the biomechanics of the volleyball spike or attack. The first section provides an overview of the spike, describing the phases of the backswing, turnswing, and forward swing. Research showed elite players achieve a greater range of motion, especially during the backswing phase. The second section examines research on injury prevention for the knees, ankles and shoulders. The final section analyzes specific components of the spike through studies of the approach, shoulder movement, ball contact height and spin. One study compared the trunk rotation and shoulder movement of elite Brazilian and Japanese players, finding differences in their spiking styles. Overall, the research helps coaches understand proper spike technique and identify factors influencing power
Lower limb alignment in young female athletes is associated with knee joint m...peertechzpublication
Background: Increased rotational forces and knee valgus forces puts strain on the anterior cruciate
ligament, frequently ruptured in female athletes. Increased internal hip rotation and increased knee valgus
alignment, possible risk factors for anterior cruciate ligament rupture, are more common in women than
men.
This document summarizes a study on the biomechanics of the instep kick in soccer. The study investigated factors that affect the efficiency of the instep kick, including last stride length, angle of thigh flexion/extension, and relationship of velocity between body joints. Three subjects performed instep kicks that were analyzed using APAS and Kinovea systems. The results showed that a longer last stride length, greater thigh extension angle, and smaller knee flexion angle contributed to higher ball velocity and kicking accuracy. Subject 3 generally demonstrated biomechanical parameters that were more favorable for an accurate instep kick.
Relationship between Selected Anthropometric Measurement and Volleyball Playe...Sports Journal
The present study was undertaken to find out the significant relationship of selected anthropometric variables with the volleyball playing performance. 25 university level male volleyball players from Guru Ghasidas Univertsity, Bilaspur were selected as a subject for the present study with age range between 18 to 22 years. The following anthropometric variables i.e. Height, Weight, Arm length and Leg length variables were selected for the testing the hypothesis. The playing performance was analyzed by three experts through subjective observation. Pearson’s Product Moment correlation test was employed for the present study and the level of significance was set at 0.05. The statistical test was computed by using standard statistical package SPSS 16. Analysis of the results indicated that Height and Leg length from the anthropometric variables were shown the significant relationship with the volleyball playing performance.
663229 - Reliability of Power Output in Single Leg Counter Movement Jump in E...Sergio Gaggioni
This document summarizes a study that assessed the reliability of using single leg countermovement jumps (CMJs) to measure power output in elite rugby players. Twenty professional rugby players performed 3 maximal single leg CMJs with each leg. Power output was measured using a force platform. Results showed excellent reliability for power output measurements between jumps, with intraclass correlation coefficients of 0.963-0.974 for left and right legs. Power output was similarly reliable when comparing forwards and backs, suggesting single leg CMJs could reliably measure limb asymmetries and be used to assess an athlete's readiness to return to play following injury. However, further research is needed to address limitations like jumping form.
This study investigated the effect of shoes containing nanosilica particles on knee valgus angle during landing in active females. Fourteen active females performed drop jump and single leg drop landing tasks barefoot and while wearing shoes with polyvinyl chloride outsoles or thermoplastic elastomer and nanosilica particle outsoles. Knee valgus angle was lowest while wearing the nanosilica particle shoe and highest barefoot. The nanosilica particle shoe reduced knee valgus angle more than the polyvinyl chloride shoe. Drop jump landing produced greater knee valgus than single leg landing. The nanosilica particle shoe appears to improve control of knee movement during landing.
Effect of shoes containing nanosilica particles on knee valgus in active fema...Nanomedicine Journal (NMJ)
Abstract
Objective(s):
The effect of silica nanoparticles (SNPs) in sport shoes outsoles on the parameters related to anterior cruciate ligament (ACL) Injury has not been investigated. The aim of this study was to investigate the effect of shoes outsole containing a composite of thermoplastic elastomer based on styrene-butadiene and silica nanoparticles (TPEN shoe) on Knee Valgus Angle (KVA) as a risk factor of ACL injuries during landing.
Materials and Methods:
Fourteen active healthy women without knee injuries and disorders performed bilateral drop jump (DJ) and single leg drop landing (SLL) tasks in barefoot, wearing shoes fabricated with polyvinyl chloride outsole (PVC shoe) and TPEN shoes conditions , randomly. The knee valgus angle values of right and left legs were calculated in the landing conditions. Two factors repeated measures ANOVA were used to investigate the effect of landing and footwear conditions on KVA of right and left legs.
Results:
For both left and right limbs, the KVA was at maximum and minimum values during landing with barefoot and TPEN shoes, respectively. PVC shoe significantly reduced the knee valgus by 3.84% in left and 4.18% in right knee (P<0.05)><0.05).
Conclusion:
Shod landing and specially TPEN shoe decreases KVA compared to barefoot. Our results suggested that using SNPs could produce some viscoelasticity property and a better joint movement control in shoe outsoles which can reduce KVA and consequent reduction of ACL Injury.
A STUDY ON THE MOTION CHANGE UNDER LOADED CONDITION INDUCED BY VIBRATION STIM...csandit
To assist not only motor function but also perception ability of elderly and/or handicapped
persons, the power-assist robots which have perception-assist function have been developed.
These robots can automatically modify the user’s motion when the robot detects inappropriate
user’s motion or a possibility of accident such as collision between the user and obstacles. For
this motion modification in perception-assist, some actuators of power-assist robot are used. On
the other hand, since some elderly persons, handicapped persons or some workers need not use
power-assist function but perception-assist function only, another new concept perception-assist
method was investigated in our previous study. In this perception-assist method, only vibrators
are used for generating motion change with kinesthetic illusion to assist perception-ability only.
In this study, since the perception-assist is often used during tasks under a loaded condition, the
features of motion change under the loaded condition are investigated.
Muscular strength, functional performances and injury risk in professional an...Fernando Farias
Muscle strength and anaerobic power of the lower extre-
mities are neuromuscular variables that influence perfor-
mance in many sports activities, including soccer. Despite
frequent contradictions in the literature, it may be assumed
that muscle strength and balance play a key role in targeted
acute muscle injuries. The purpose of the present study was
to provide and compare pre-season muscular strength and
power profiles in professional and junior elite soccer players
throughout the developmental years of 15–21.
An 8-week study investigated the effects of a throwing exercise program using TheraBands on male volleyball players with glenohumeral internal rotation deficit (GIRD). Sixty players were randomly assigned to an experimental group, which did the throwing exercises 3 times per week, or a control group. The experimental group demonstrated statistically significant improvements in electromyography activity of shoulder muscles, internal rotation range of motion, rotator cuff strength ratio, and joint position sense after the program. The study suggests throwing exercises with TheraBands can benefit athletes with GIRD.
IRJET- A Review on Biomechanics of Knee JointIRJET Journal
This document reviews the biomechanics of the knee joint. It discusses the role of the knee joint in allowing locomotion with minimal energy and stability over different terrains. The document outlines the movements of the knee including flexion, extension, and rotation. It describes the forces acting on the knee joint, which can be 2-3 times body weight during walking. The document provides an example calculation of the net joint forces and moments at the knee using inverse dynamics. It determines the horizontal and vertical reaction forces at the knee and calculates the net joint moment to be 592.3 Nm, indicating knee extension.
Comparative effect of SAQ and circuit training programme on selected physical...Sports Journal
The present study was undertaken to study the comparative effect of SAQ and circuit training program on
selected physical fitness variables of school level basketball players. Thirty (30) school level basketball
players aged between 14-17 years will randomly be selected from Simpkins School Agra U.P. The
subjects were randomly divided in three groups as group A (SAQ training group), group B (circuit
training group) and group C (control group). After the pre-test with Physical fitness test Experiment
Group-A underwent a training SAQ programme of selected exercise. Experiment Group-B received a
Circuit training program of selected exercises, whereas the Control group did not participate in any
training program. Group A has gone under SAQ training program and Group has gone under circuit
training for 60 minutes three times a week except Sunday for duration of 12 weeks. Post data was
collected after 12 weeks of experimental period. Analysis of Variance (ANOCOVA) was applied at 0.05
level of significance and Post hoc mean comparison was done by using LSD test. It may be concluded
that SAQ training program was significantly better than circuit training program for speed and agility
whereas circuit training program was better than SAQ training program for abdominal, arms & shoulder
endurance being studied by the researcher. In case of explosive strength no significant difference was
found between both the training programs
A study of selected biomechanical variables as a factor of hitting performanc...IOSR Journals
Abstract: The modern age of sports is the excellence, so in every sports perfection and purification of skill has
got its immense importance. Biomechanics is an applied form of mechanics and consequently the method used
to investigate it must be derived from those of mechanics. Biomechanics aim to explain the mechanics of life.
Sports biomechanics have also generated other efforts at improving athletic performance in different games and
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Introduction
Tom Cruise long hair has often been more than a style choice. it has been a significant element of his persona both on and off the screen. From the tousled locks of the rebellious Maverick in "Top Gun" to the sleek, sophisticated mane in "Mission: Impossible II." Cruise's hair has played a pivotal role in shaping his image and the characters he portrays. This article explores the various stages of Tom Cruise long hair. Examining how this iconic look has evolved and influenced his career and broader fashion trends.
Early Days: The Emergence of a Style Icon
The 1980s: The Birth of a Star
In the early stages of his career during the 1980s, Tom Cruise sported a range of hairstyles. but in "Top Gun" (1986), his hair began to gain significant attention. Though not long by later standards, his hair in this film was longer than the military crew cuts associated with fighter pilots. adding a rebellious edge to his character, Pete "Maverick" Mitchell.
Risky Business: The Transition Begins
In "Risky Business" (1983). Tom Cruise's hair was short but longer than the clean-cut styles dominant at the time. This look complemented his role as a high school student stepping into adulthood. embodying a sense of youthful freedom and experimentation. It was a precursor to the more dramatic hair transformations in his career.
The 1990s: Experimentation and Iconic Roles
Far and Away: Embracing Length
One of the first films in which Tom Cruise embraced long hair was "Far and Away" (1992). Playing the role of Joseph. an Irish immigrant in 1890s America, Cruise's long, hair added authenticity to his character's rugged and determined persona. This look was a stark departure from his earlier. more polished styles and marked the beginning of a more adventurous phase in his hairstyle choices.
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Mission: Impossible II: The Pinnacle of Long Hair
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The city of Ravens burg was known for its gothic architecture, fog-covered streets, and an eerie silence that seemed to hang over the town like a shroud.
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Tom Cruise Daughter: An Insight into the Life of Suri Cruisegreendigital
Tom Cruise is a name that resonates with global audiences for his iconic roles in blockbuster films and his dynamic presence in Hollywood. But, beyond his illustrious career, Tom Cruise's personal life. especially his relationship with his daughter has been a subject of public fascination and media scrutiny. This article delves deep into the life of Tom Cruise daughter, Suri Cruise. Exploring her upbringing, the influence of her parents, and her current life.
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Introduction: The Fame Surrounding Tom Cruise Daughter
Suri Cruise, the daughter of Tom Cruise and Katie Holmes, has been in the public eye since her birth on April 18, 2006. Thanks to the media's relentless coverage, the world watched her grow up. As the daughter of one of Hollywood's most renowned actors. Suri has had a unique upbringing marked by privilege and scrutiny. This article aims to provide a comprehensive overview of Suri Cruise's life. Her relationship with her parents, and her journey so far.
Early Life of Tom Cruise Daughter
Birth and Immediate Fame
Suri Cruise was born in Santa Monica, California. and from the moment she came into the world, she was thrust into the limelight. Her parents, Tom Cruise and Katie Holmes. Were one of Hollywood's most talked-about couples at the time. The birth of their daughter was a anticipated event. and Suri's first public appearance in Vanity Fair magazine set the tone for her life in the public eye.
The Impact of Celebrity Parents
Having celebrity parents like Tom Cruise and Katie Holmes comes with its own set of challenges and privileges. Suri Cruise's early life marked by a whirlwind of media attention. paparazzi, and public interest. Despite the constant spotlight. Her parents tried to provide her with an upbringing that was as normal as possible.
The Influence of Tom Cruise and Katie Holmes
Tom Cruise's Parenting Style
Tom Cruise known for his dedication and passion in both his professional and personal life. As a father, Cruise has described as loving and protective. His involvement in the Church of Scientology, but, has been a point of contention and has influenced his relationship with Suri. Cruise's commitment to Scientology has reported to be a significant factor in his and Holmes' divorce and his limited public interactions with Suri.
Katie Holmes' Role in Suri's Life
Katie Holmes has been Suri's primary caregiver since her separation from Tom Cruise in 2012. Holmes has provided a stable and grounded environment for her daughter. She moved to New York City with Suri to start a new chapter in their lives away from the intense scrutiny of Hollywood.
Suri Cruise: Growing Up in the Spotlight
Media Attention and Public Interest
From stylish outfits to everyday activities. Suri Cruise has been a favorite subject for tabloids and entertainment news. The constant media attention has shaped her childhood. Despite this, Suri has managed to maintain a level of normalcy, thanks to her mother's efforts.
Tom Cruise Daughter: An Insight into the Life of Suri Cruise
17 mohd arshadbari_finalpaper_7
1. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 3
Biomechanical Analysis of Flex Elbow on Bowling Speed in Cricket
Ikram Hussain
(Professor and Chairman)
Department of Physical Health and Sports Education,
Aligarh Muslim University, Aligarh, 202002, (U.P.), India.
E-mail: ikram.husain@gmail.com
Mohd. Arshad Bari
(Lecturer)
Corresponding author
Department of Physical Health and Sports Education,
Aligarh Muslim University, Aligarh, 202002, (U.P.), India.
E-mail: sbiomech90@gmail.com
Mohd. Imran
Department of Physical Health and Sports Education,
Aligarh Muslim University, Aligarh, 202002, (U.P.), India.
E-mail: imranphe09@yahoo.com.in
The authors would like to acknowledge the cooperation of UGC-SAP (DRS-I) Programme, Department of Physical
Health and Sports Education, Aligarh Muslim University, Aligarh
Abstract
Bowling in cricket is traditionally thought to be a rigid-arm motion, allowing no elbow straightening during the
delivery phase. Conversely, research has shown that a perfectly rigid arm through delivery is practically
unattainable, which has led to rule changes over the past years. The current rule requires a bowler not to increase the
elbow angle by more than 158, thus requiring a measurement to confirm legality in “suspect” bowlers. This study
examined whether such bowlers can produce an additional contribution to wrist/ball release speed by internal
rotation of the upper arm. The kinematics of a bowling arm were calculated using a simple two-link model (upper
arm and forearm). Using reported internal rotation speeds of the upper arm from baseball and bowling arm
kinematics from cricket, the change in wrist joint speed was analysed as a function of effective arm length, and wrist
distance from the internal rotation axis. A significant increase in wrist speed was noted. This suggests that bowlers
who can maintain a fixed elbow flexion during delivery can produce distinctly greater wrist/ball speeds by using
upper arm internal rotation.
Keywords: kinematics, biomechanics, bowling, cricket, elbow flexion.
2. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 3
1. Introduction
The resolve of bowling in cricket is to deliver the ball to the batter so that the ball is hard for the batsman to counter,
either through its speed or spin. Most bowlers commence with a smooth, rhythmical run-up to generate linear
momentum which is channelized during the delivery stride to propel the upper body over the front leg. This activity
generates the angular velocity of the bowling arm as it circumducts the glenohumeral joint. It is proposed that the
development of wrist speed is equally important to spin and fast bowlers, in that it lends to the angular or linear
speeds of the ball respectively.
The fast bowling action can be classified as side-on, front-on, semi-front-on or mixed depending on the
orientation of the shoulder, hip axes and back foot alignment during delivery. Bowlers who use the side-on and
front-on techniques are not at as much risk of injury as those who use the mixed technique. The semi-front-on action
is a new technique that is based on the same principles as the two `safe actions’, where the alignment of the
shoulders and hips are in the same direction. The mixed action features a realignment of the shoulders in the
transverse plane during the delivery stride, which causes an increase in lumbar spine axial rotation, extension±
flexion and lateral flexion. All these features occur cumulatively in a very short time when ground reaction forces
are high. A combination of these factors has been linked to an increased incidence of radiological features in the
thoracolumbar spine, including spondylolysis, intervertebral disc degeneration and spondylolisthesis (Foster et al.,
1989; Elliott et al., 1992; Burnett et al., 1996). Spondylolisthesis was reported in 50% of A-grade fast bowlers over
a period of 5 years by Payne et al. (1987) and has been found to represent 45% of bony abnormalities reported by
retired, elite fast bowlers (Annear et al., 1992).
Biomechanical evaluation supports the claim that he maintains a constant elbow flexion angle throughout
delivery (Lloyd et al., 2000). Elbow flexion is not only restricted to spin bowlers. In the past, fast bowlers such as
Ian Meckiff (Australia) and Charlie Griffith (West Indies) were considered by some to bowl with a flexed elbow.
Recently, however, the whole issue of elbow flexion in fast bowling has re-emerged after the two of theworld's
fastest bowlers, Shoaib Akhtar (Pakistan), Imtiaz Ahmed (India) and Brett Lee (Australia), were cited by umpires
for a possible infringement of the bowling law. The use of internal rotation of the upper arm in cricket bowling to
assist in the development of wrist/ball speed has not been examined and it appears some bowlers may utilise this
technique. Previous work (Elliott et al., 1995; 1996; 1997) has clearly shown the importance of upper arm internal
rotation in contributing to racquet-head speed in tennis and squash. Further, Marshall and Elliott (2000) suggested
that internal rotation was a significant factor in most overarm throwing or striking activities. The purpose of this
study is to investigate the mechanics of bowling with a flexed elbow, and to determine whether there is any
advantage with respect to wrist/ball speed in doing so.
2. Methodology:
Six (06) cricket players from Narashans Cricket Academy (NCA), Aligarh were randomly selected for the
purpose of the study. They performed bowling during training session. The mean age of the cricket players were age
(18.98 years), height – (167.87 cm.), weight (53.29 kg.). For the acquisition of kinematical data, the subject’s
throwing motion were recorded using Canon Legaria SF-10, 8.1 Mp video camera in a field setting operating at a
nominal frame rate of 60 Hz and with a shutter speed of 1/2000 s and at 60fps . The camera was set-up on a rigid
tripod and secured to the floor in the location at a distance of 12 meter from the point of throw. The camera was
positioned perpendicular to the sagittal plane and parallel to the mediolateral axis (camera optical axes perpendicular
on the sigittal plane) as their throwing arm giving approximately a 90 o between their respective optical axes. The
camera was also elevated to 95 cms and tilted down in order to get the image of the subject as large as possible
while that all points of interested within one frame.
The recorded video footages were downloaded, slashed and edited by using the downloaded version of STHVCD55,
Sony Vegas pro- 10software. Digitization, smoothing and analysis were conducted using the Silicon Coach Pro7
motion analysis software.
3. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 3
Figure 1 The basic bowling technique (right-hand bowler) has many characteristics: the run-up, leap, right foot contact, left
arm motion, bowling arm rotation, left foot contact, ball release, and follow-though in respect to wrist linear velocity phase by
phase.
For a straight bowling arm, ball velocity (BVe) can be considered to be the sum of the linear velocity of the
shoulder (LVSh) plus the linear velocity of the wrist (LVWr) resulting from arm motion (ῲA Am) plus the linear
velocity of the hand (LVh) as a result of hand flexion (ῲA Hf) (Figure 2). This analysis examines the changes to the
LVwr component of ball speed as a result of elbow flexion. We assume changes to wrist speed would have the same
effect on ball speed for both straight and flexed elbow deliveries.
4. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 3
Figure 2. The bowling arm represented as a simple two-link model, showing the contribution of arm and
hand flexion angular velocity to wrist and ball velocity.
Bowlers who have a flexed elbow during the latter stages of delivery carry the ball in the hand at some
distance from the upper arm internal rotation axis, providing the opportunity to take advantage of this segmental
rotation to contribute to ball speed. A two-link model representing the upper arm and forearm was used to compare
the wrist/ball speed produced by a straight or a flexed bowling arm during delivery. Thus, to the ball speed
contribution formula we now add the upper arm internal rotation angular velocity (ῲ IR) times the ball-internal
rotation axis distance (ῲ D). However, since a flexed elbow also decreases the shoulder-wrist distance (rf < TA), it
is necessary to consider the reduction in the contribution to ball speed from the arm's angular flexion velocity (ῲ A).
3. Results.
The resultant arm length (rA) decreases as the flexion angle (0) is increased whereas the effective wrist-
internal rotation axis distance (d) increases (Table 1). With an increase in elbow flexion angle to 35°, the resultant
arm length decreases minimally (0.043 m) while distance d increases to 0.167 m.
5. Innovative Systems Design and Engineering www.iiste.org
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Vol 2, No 3
Table 1 The Resulting Shoulder-Wrist Distance and the Effective Wrist-Internal Rotation Axis Distance as a
Result of Elbow Flexion.
Elbow flexion
Resultant bowling arm length (m) Effective wrist-IR axis distance (m)
Angle degree
Degree (ᶿ)
Mean SD Mean SD
00 0.473 0.027 0.000 0.000
05 0.470 0.028 0.022 0.015
10 0.463 0.023 0.040 0.024
15 0.459 0.022 0.060 0.030
20 0.452 0.023 0.068 0.026
25 0.445 0.016 0.093 0.036
30 0.440 0.023 0.135 0.052
35 0.433 0.022 0.167 0.049
As ᶿ is changed from 5° to 35° the increase in wrist speed due to internal rotation at either 1950 0/s or 4600
0
/s becomes increasingly greater than the loss in wrist speed due to a decrease in forearm length. For example, with
an elbow flexion of 35°, the loss in wrist speed due to the decrease in rf is 1.20 m/s while the gain from the use of
internal rotation could be between 4.71 m/s and 11.34 m/s. Few authors have reported angular velocities of the arm
for bowling, although calculations based on the data in the review by Bartlett et al. (1996) suggest a value of
approximately 1700 7s (30 r/s) is required to produce the recorded ball speeds. Vaughn (1985) and Feltner and
Dapena (1986) have reported upper arm internal rotation speeds of about 5700 7s (100 r/s) in baseball pitching and
Feltner and Nelson (1996) reported internal rotation speeds of 2000 7s (35 r/s) in a waterpolo throw. Note that the
internal rotation speeds achievable are influenced by the mass of the ball being thrown, and thus it might be
expected that bowlers would achieve speeds closer to those of baseball pitchers than water polo players.
4. Discussion
Most bowlers do not hold a flexed elbow during the second stages of delivery. This effectively invalidates
the possible contribution of upper arm internal rotation, which is a major subscriber to ball or racquet speed in most
other throwing (Marshall and Elliott, 2000). From our calculations, bowlers using a flexed elbow during delivery
may be able to produce a clear-cut advantage when originating wrist speed. The generation of wrist speed via upper
arm internal rotation significantly outweighs any loss of wrist speed due to a reduction in effective bowling arm
length. the range of elbow angles (5-35°) used and the slow internal rotation speed of 1950 °/s the net gain in wrist
speed (and therefore ball speed) was between 0.72^136 m/s). Internal rotation speed is limited by the mass of the
ball, and thus one would expect greater internal rotation speeds than this during the delivery of a cricket ball. While
speeds equivalent to baseball pitching might not be generated, it is likely the gains in speed would be greater than
those suggested above. Therefore, it does not matter whether a bowler consciously maintains a flexed elbow during
delivery, or has an elbow deformity either of the fixed flexion or carry angle type — both provide the potential for
substantially increased wrist and ball speed through the use of internal rotation of the upper arm.
6. Innovative Systems Design and Engineering www.iiste.org
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Vol 2, No 3
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