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2020

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The Relationship Between Trunk Kinematic Variables And Underwater Undulatory Swimming Performance In Competitive Swimmers, Takahiro Tanaka, Takahiko Sato, Satoru Hashizume, Naruhiro Shiozawa, Tadao Isaka Jul 2020

The Relationship Between Trunk Kinematic Variables And Underwater Undulatory Swimming Performance In Competitive Swimmers, Takahiro Tanaka, Takahiko Sato, Satoru Hashizume, Naruhiro Shiozawa, Tadao Isaka

ISBS Proceedings Archive

The purpose of this study was to examine the relationship between selected trunk kinematic variables and undulatory underwater swimming performance in competitive swimmers. Eight male and 2 female swimmers performed 15 m UUS with their maximum efforts. Three-dimensional coordinate of markers attached to bony configurations were corrected during Pearson’s product moment by using the underwater motion capture system. The range of motion and the corresponding angular velocity were computed for lower waist, upper waist and chest. The relationship between horizontal velocity of center of mass and each kinematic variable was then examined. No significant correlations were found between horizontal velocity …

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The Effect Of Marker Placement Error On The Interpretation Of Inter-Limb Differences In Frontal Plane Knee Loading During A Change Of Direction Task, Ciaran Mcfadden Jul 2020

The Effect Of Marker Placement Error On The Interpretation Of Inter-Limb Differences In Frontal Plane Knee Loading During A Change Of Direction Task, Ciaran Mcfadden

ISBS Proceedings Archive

Inter-limb differences in frontal plane knee loading have been observed during change of direction tasks following anterior cruciate ligament reconstruction. Objective assessment of these differences may be a useful means of monitoring rehabilitation, but their robustness to methodological sources of error such as marker placement must be established prior to any clinical implementation. The aim of this investigation was to determine the effect of random marker placement error on the interpretation of inter-limb differences in frontal plane knee loading during a change of direction task. Participants completed three trials of a 90° change of direction task on both limbs. Simulated …

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Influence Of Calculation Parameters On Nonlinear Dynamics Measures, Arezoo Amirpourabasi, Jia Yi Chow, Domenico Vicinanza Dr, Genevieve Kr Williams Jul 2020

Influence Of Calculation Parameters On Nonlinear Dynamics Measures, Arezoo Amirpourabasi, Jia Yi Chow, Domenico Vicinanza Dr, Genevieve Kr Williams

ISBS Proceedings Archive

Nonlinear analysis methods based on a dynamical systems approach have become more prevalent in recent biomechanics studies. The aim of this study is to identify the range of time delay and embedding dimension values estimated for gait data, and how sensitive Lyapunov exponent and correlation dimension are to the range of these values. A participant walked at 3 km/h and ran at 9 km/h on a treadmill for 2 minutes. Lyaponuv exponent and correlation dimension were calculated based on a combination of the optimal and mean average time delay (TD) and embedding dimension (ED) for both angle and marker data. …

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Biomechanical Investigation Of The Kizami Tsuki In Karate Athletes, Valentina Camomilla, Foresti Adriano, Riccardo Annibali, Paola Sbriccoli, Federico Quinzi Jul 2020

Biomechanical Investigation Of The Kizami Tsuki In Karate Athletes, Valentina Camomilla, Foresti Adriano, Riccardo Annibali, Paola Sbriccoli, Federico Quinzi

ISBS Proceedings Archive

The purpose of this study was to investigate the kinematics and kinetics characteristics of kizami tsuki karate punch technique. Punching actions represent the most frequently performed attacking techniques in karate combat competitions (75% of total actions, kizami tsuki being the most common). Six athletes were asked to perform three kizami tsuki against a hand-held target at their maximal speed. Punch kinematics and kinetics were recorded by means of stereophotogrammetry and forceplates. Power, lower and upper limb kinematics and their coordinative pattern during the punching actions were assessed to characterize the technique. A multiple linear regression model was devised to …

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Technique Selection During Landings In Artistic Gymnastics, Rebecca Straker, Tim Exell, Roman Farana, Joseph Hamill, Gareth Irwin Jul 2020

Technique Selection During Landings In Artistic Gymnastics, Rebecca Straker, Tim Exell, Roman Farana, Joseph Hamill, Gareth Irwin

ISBS Proceedings Archive

This study aimed to quantify the mechanical characteristics of two landing techniques performed by artistic gymnasts. Seven senior female artistic gymnasts performed 20 drop landings with different foot positions: feet together (women’s technique) or hip width apart (men’s technique). Synchronised 3D kinematic (250 Hz) and kinetic data (1000 Hz) were collected for each trial and biomechanical variables associated with lower extremity injury during landing were analysed. Significant differences (α < 0.05) in ankle dorsiflexion and inversion at peak vertical ground reaction force (FPeakZ) were identified between techniques. The findings suggest the female landing style to be associated with increased FPeakZ, loading rate and reduced knee flexion. Whereas the male landing …

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Undergraduate Student Experiences Of Publishing Biomechanics Research, Stuart A. Mcerlain-Naylor Jul 2020

Undergraduate Student Experiences Of Publishing Biomechanics Research, Stuart A. Mcerlain-Naylor

ISBS Proceedings Archive

The aim of this study was to investigate student experiences of publishing undergraduate research in biomechanics. Twenty-five individuals with experience of publishing peer-reviewed undergraduate biomechanics research completed an online survey regarding their perceived benefits and their level of involvement in various aspects of the research process. Areas of the greatest and least perceived benefits and student involvement were identified. Correlations suggested numerous beneficial effects of relatively low student involvement, more likely related to the concurrent greater supervisor involvement. Staff should make informed decisions regarding their level of involvement in each aspect of the research process rather than simply focusing on …

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Vertical Power-Force-Velocity Profiling: Reliability Comparison Of Mulitple- And Two-Point Methods, Isabella Fessl, Julian Fritz, Josef Kröll Jul 2020

Vertical Power-Force-Velocity Profiling: Reliability Comparison Of Mulitple- And Two-Point Methods, Isabella Fessl, Julian Fritz, Josef Kröll

ISBS Proceedings Archive

Power-Force-velocity (P-F-v) profiling is an approach used for performance diagnostics to assess an athlete’s anaerobic performance level. The aim of the study was to determine and compare the test-retest reliability of the 5p-method and the 2p-method for a group of sport students. With respect to the 2p-method this was the first study to determine the reliability using an independent data-set for vertical jumps. Acceptable reliability (ICC > 0.78, CV < 7.6%, no significant differences) was obtained for the variables F0, v0 and Pmax obtained through the 5p-method. Using the 2p-method acceptable reliability was just found for the variables F0 and Pmax. Therefore, the use of …

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The Effect Of Step Width Control On Load Carriage Economy, Sean Hudson, Chris Low, Carlton Cooke, Benedicte Vanwanseele, Ray Lloyd Jul 2020

The Effect Of Step Width Control On Load Carriage Economy, Sean Hudson, Chris Low, Carlton Cooke, Benedicte Vanwanseele, Ray Lloyd

ISBS Proceedings Archive

The purpose of this study was to assess the influence of step width on load carriage economy. Fifteen healthy volunteers (age = 25 ± 3 years; stature = 1.78 ± 0.07 m; body mass = 73.6 ± 10.1 kg) completed three trials in a randomised order. Each trial differed by load carriage method and involved walking on a force-instrumented at 3km.h-1 with 0, 3, 12 and 20 kg. This protocol was then repeated with step width controlled to each participant’s preferred unloaded width. Relative load carriage economy was measured using the Extra Load Index (ELI). Load carriage …

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Differences In Reaction Force-Time Characteristics Experienced By Females When Running On A Track At Different Speeds, Harper E. Stewart, Jill L. Mcnitt-Gray Jul 2020

Differences In Reaction Force-Time Characteristics Experienced By Females When Running On A Track At Different Speeds, Harper E. Stewart, Jill L. Mcnitt-Gray

ISBS Proceedings Archive

Elite collegiate runners are susceptible to sustaining lower extremity stress related injuries. Ground reaction forces (GRFs) were analyzed to understand differences in mechanical loading at steady state 5.5 and 7 min/mile paces. We hypothesized GRF magnitudes would increase with speed while horizontal GRFs during braking would be unique to each participant. GRFs, inertial measurement units, and high speed video were collected during outdoor over ground running. Group differences were observed that were not always significant within participant. As speed increased, average horizontal GRF during braking (-0.25 to -0.29 BWs) decreased while peak vertical GRF increased (2.75 to 2.91 BWs). The …

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Kinematic Differences Between Sprinting And The Hurdle Jump Exercise – A Preliminary Analysis, Robin Healy, Richard Bolger, Ian C. Kenny, Andrew J. Harrison Jul 2020

Kinematic Differences Between Sprinting And The Hurdle Jump Exercise – A Preliminary Analysis, Robin Healy, Richard Bolger, Ian C. Kenny, Andrew J. Harrison

ISBS Proceedings Archive

The hurdle jump is a commonly prescribed plyometric exercise for sprint athletes. The purpose of this study was to assess the lower body kinematic differences between maximal velocity sprinting and hurdle jumps performed over a range hurdle heights. Six competitive male sprinters performed maximum effort sprints over 50 m and hurdle jumps over 0.60, 0.75 and 0.90 m. Ground contact times, ankle, knee, and hip angles were collected during the ground contact phase of all trials. Significantly lower peak dorsiflexion angles and lower mean ground contact times were found in sprinting compared to all three hurdle jump conditions (all p < 0.015). The hurdle jump exercise may be a suitable exercise for sprint athletes due to the greater demand imposed on the athlete relative to maximum velocity sprinting. Coaches are advised to monitor ground contact times to ensure the intensity of the exercise is not excessive.

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Landing Asymmetry In Back Tucked Saltos And The Effect Of Takeoff Asymmetry, Nicolas B. Hallgrimson, Alison Oates, Marta Erlandson, Joel Lanovaz Jul 2020

Landing Asymmetry In Back Tucked Saltos And The Effect Of Takeoff Asymmetry, Nicolas B. Hallgrimson, Alison Oates, Marta Erlandson, Joel Lanovaz

ISBS Proceedings Archive

Landing asymmetry is an injury risk factor in gymnastics. This study examined whether takeoff force asymmetry is related to landing asymmetry during back tucked saltos in competitive gymnasts. Each gymnast performed an isometric leg strength test followed by multiple back tucked salto trials with no takeoff instruction, leaning with 60% asymmetry to the right, and 60% asymmetry to the left using a standard asymmetry index. Forces were measured at takeoff and landing. The novel experimental approach successfully produced distinct takeoff asymmetry levels. There was a significant rightward asymmetry in baseline landing peak vertical force, possibly due to right leg strength …

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The Effect Of Visual Gaze Location On Block-Start Biomechanics In Athletics, Marcus Lee, Michael Chan, Mitsuo Otsuka, Desmond Boey Jul 2020

The Effect Of Visual Gaze Location On Block-Start Biomechanics In Athletics, Marcus Lee, Michael Chan, Mitsuo Otsuka, Desmond Boey

ISBS Proceedings Archive

This study investigated the effects of varying visual gaze location (VGL), by means of externally-focused instruction, during the block-start “set” phase with the intention of optimizing block-start biomechanics for faster starts in an athlete-specific manner. Nine collegiate sprinters performed a series of block-starts while directing their VGL to their personal baselines, and at 0.5m, 1m, 2m and 3m from the start line. Twelve infrared opto-reflective cameras and one force plate were utilized to assess trunk, hip, knee and centre of mass kinematics, and blocks push-phase kinetics. An eyetracker was used to determine participants’ VGL. Some postural changes observed were a …

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The Contribution Of Body Center Of Mass Velocity To Basketball Ball Release Velocity Across Shot Distances, Casey Wiens, Jill L. Mcnitt-Gray Jul 2020

The Contribution Of Body Center Of Mass Velocity To Basketball Ball Release Velocity Across Shot Distances, Casey Wiens, Jill L. Mcnitt-Gray

ISBS Proceedings Archive

This study investigated the contribution of the body center of mass velocity to basketball ball velocity at release when taking shots from different distances from the hoop. Seven basketball players with ten years of experience performed at least ten shots from progressively greater distances: close (< 2.5 m), medium (4.57 m, free throw line), and long (6.02 m, American high school three-point line). As the distance from the hoop increases, the ball velocity required at release increases. Our hypothesis was that an increase in the shot distance would increase the contribution of the body center of mass velocity to ball velocity at release was hypothesized. Kinematics of the ball were recorded using video. Reaction forces generated by each leg were measured using two force plates and used to determine the velocity of the body center of mass during the shooting motion. The results indicate that the percent contribution of the body center of mass velocity to ball velocity at release increased, and the arm contribution decreased with an increase in shot distance. Releasing the ball earlier in the body center of mass trajectory before the apex resulted in a greater percent body contribution of the center of mass vertical velocity to ball vertical velocity.

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Frontal Plane Alignment During Forehand And Backhand Lawn Bowls Deliveries, Kane Middleton, Kate Webster, Samantha Birse, Jodie Mcclelland Jul 2020

Frontal Plane Alignment During Forehand And Backhand Lawn Bowls Deliveries, Kane Middleton, Kate Webster, Samantha Birse, Jodie Mcclelland

ISBS Proceedings Archive

There is very little research on the biomechancis of the lawn bowls delivery. Bowls are commonly delivered using either a forehand or backhand technique. The purpose of this study was to compare the pelvis, trunk and upper limb kinematics of the forehand and backhand lawn bowls delivery. Elite lawn bowlers (n=18) who were competing at international level performed a series of forehand and backhand lawn bowls deliveries on a simulated indoor bowling rink. Differences were found between the delivery types for pelvis and trunk segment angles but there were no differences in upper limb frontal plane joint angles at the …

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The Relationship Between Achilles Tendon Dimensions And Foot Strike Index In Rearfoot And Non-Rearfoot Runners, Jiri Skypala, Joseph Hamill, Daniel Jandacka Jul 2020

The Relationship Between Achilles Tendon Dimensions And Foot Strike Index In Rearfoot And Non-Rearfoot Runners, Jiri Skypala, Joseph Hamill, Daniel Jandacka

ISBS Proceedings Archive

The purpose of this study was to describe the relationship between Achilles tendon dimensions and foot strike index in rearfoot and non-rearfoot runners. 107 recreational runners were divided into a group of rearfoot (n = 88) and a group of non-rearfoot runners (n = 19). Achilles tendon dimensions were measured by a combination of ultrasonography imaging and kinematic analysis. To analyse the footfall pattern, each participant performed 8 successful trials of running at their stated self-preferred endurance speed. Partial correlation was used for statistical analysis. Runners in the group of non-rearfoot runners, whose footfall pattern is more over forefoot, have …

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The Effect Of Grip Position On Upper Limb Angular Kinematics During Tennis Topspin Double-Handed Backhand Strokes, Nicholas Busuttil, Machar Reid, Molly Connolly, Ben Dascombe, Kane Middleton Dr Jul 2020

The Effect Of Grip Position On Upper Limb Angular Kinematics During Tennis Topspin Double-Handed Backhand Strokes, Nicholas Busuttil, Machar Reid, Molly Connolly, Ben Dascombe, Kane Middleton Dr

ISBS Proceedings Archive

The purpose of this study was to compare the effect of grip on upper limb angular kinematics of sub-elite tennis players during a topspin double-handed backhand while aiming crosscourt. Sixteen sub-elite right-handed tennis players performed double-handed backhand trials using two different non-dominant grips (eastern & continental). Upper limb trajectory data was captured using the Vicon motion capture system (250 Hz). Greater peak angular velocity was observed in the eastern grip at the dominant shoulder (flexion, extension, abduction, adduction) and non-dominant shoulder (extension), elbow (pronation) and wrist (flexion, ulna and radial deviation). Subsequently peak linear velocities for the racket head (horizontal), …

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Upper Limb Kinematics During The Topspin Double-Handed Backhand Stroke In Tennis, Nicholas Busuttil, Machar Reid, Molly Connolly, Ben Dascombe, Kane Middleton Dr Jul 2020

Upper Limb Kinematics During The Topspin Double-Handed Backhand Stroke In Tennis, Nicholas Busuttil, Machar Reid, Molly Connolly, Ben Dascombe, Kane Middleton Dr

ISBS Proceedings Archive

The purpose of this study was to compare non-dominant wrist kinematics during tennis double-handed backhand strokes in players using either an eastern or continental grip position. Trajectory data for two grips (eastern & continental) and depths (deep & short) were captured for sixteen sub-elite right-handed tennis players using a 12-camera Vicon motion capture system (250 Hz). The eastern grip demonstrated significantly faster horizontal racket head velocities compared to the continental grip. However, no differences were observed in accuracy or spin rate between grips (p > 0.05). In the non-dominant upper limb for the continental condition, elbow flexion was smaller while …

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Creating Virtual Force Platforms For Cutting Maneuvers From Kinematic Data Based On Lstm Neural Networks, Dominik Fohrmann, Marion Mundt, Sina David, Arnd Koeppe, Bernd Markert, Wolfgang Potthast Jul 2020

Creating Virtual Force Platforms For Cutting Maneuvers From Kinematic Data Based On Lstm Neural Networks, Dominik Fohrmann, Marion Mundt, Sina David, Arnd Koeppe, Bernd Markert, Wolfgang Potthast

ISBS Proceedings Archive

The precise measurement of ground reaction forces and moments (GRF/M) usually requires stationary equipment and is, therefore, only partly feasible for field measurements. In this work we propose a method to derive GRF/M time series from motion capture marker trajectories for cutting maneuvers (CM) using a long short-term memory (LSTM) neural network. We used a dataset containing 637 CM motion files from 70 participants and trained two-layer LSTM neural networks to predict the GRF/M signals of two force platforms. A five-fold cross-validation resulted in correlation coefficients ranging from 0.870 to 0.977 and normalized root mean square errors from 3.51 to …

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Does Variability Play A Role In Hamstring Strain Injuries? A Pilot Study In Sprinting, Carlie Ede, Glen Blenkinsop, Sam Allen Jul 2020

Does Variability Play A Role In Hamstring Strain Injuries? A Pilot Study In Sprinting, Carlie Ede, Glen Blenkinsop, Sam Allen

ISBS Proceedings Archive

A scaled OpenSim model was used to assess the variability and changes in muscle loads across multiple strides and at different running speeds (2-8 m·s-1). Peak biceps femoris muscle fibre force, length, velocity and power occurred during the late swing phase of running and became more variable above 6 m·s-1. With each increase in running speed from 2-8 m·s-1, peak force occurred earlier in the swing, at longer muscle lengths and became less variable in its timing.Changes in variability can create a greater risk of injury and exploring these trends further may provide additional insight into hamstring strain injuries.

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Correlation Between Coordination Variability And Sprint Velocity In Different Skill Level, Liduan Wang, Feng Qu, Wei Wang Jul 2020

Correlation Between Coordination Variability And Sprint Velocity In Different Skill Level, Liduan Wang, Feng Qu, Wei Wang

ISBS Proceedings Archive

The relationship between variability and motor performance may differ among different skill level subjects.The purpose of this study was to identify the relationship between coordination variability and sprint velocity in athletes group and non-athletes group. Continuous relative phase method was used to quantify the coordination variability across trials. The results suggest that the correlation between coordination variability and sprint velocity are different in athletes group and non-athletes group. For Hip-Knee coordination variability of braking phase, in athletes group, there was a significant negative correlation between variability and sprint velocity, the faster the velocity was, the less variability was. But in …

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A Novel Method For Comparing Vector Coding Profiles, Adam Brazil, Laurie Needham, Timothy Exell, Cassie Wilson, Gareth Irwin Jul 2020

A Novel Method For Comparing Vector Coding Profiles, Adam Brazil, Laurie Needham, Timothy Exell, Cassie Wilson, Gareth Irwin

ISBS Proceedings Archive

The aim of this study was to present a new method for comparing intra-limb coordination profiles utilising vector coding and coordination binning approaches. Three-dimensional kinematic data (250 Hz) were collected from six male sprinters performing bilateral and unilateral 30 cm drop jumps. Vector coding techniques were applied to sagittal plane angle-angle plots for the hip-knee, hip-ankle and knee-ankle joint couples and resulting coupling angles were binned into eight distinct coordination patterns. A ‘difference score‘ was calculated to provide discrete and continuous comparison of coordination profiles between each task. The method presented offers a simple, practical way for researchers and practitioners …

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Fatigue Leads To Altered Spinal Kinematics During High Performance Ergometer Rowing, Caryn A. Urbanczyk, Emma Miller, Alison H. Mcgregor, Anthony Mj Bull Jul 2020

Fatigue Leads To Altered Spinal Kinematics During High Performance Ergometer Rowing, Caryn A. Urbanczyk, Emma Miller, Alison H. Mcgregor, Anthony Mj Bull

ISBS Proceedings Archive

Low back injuries in rowing are attributed to intense, repetitive, loading through the spine. Good technique and postural control are essential to maximize performance and minimize injury risk. This motion capture study recorded 3D spinal kinematics of 14 athletes during rowing at varying speeds on an instrumented ergometer and correlated motion with power metrics and athlete demographics. Sagittal plane rotation decreases in the lumbar spine and increases in the thoracic spine as speed increases. Transverse and frontal planes have little influence on force output. Declining postural control can be seen within each trial and worsened with higher rate. Assessments of …

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Can Increased Midsole Bending Stiffness Of Sport Shoes Delay The Onset Of Lower Limb Joint Work Redistribution During A Prolonged Run?, Sasa Cigoja, Jared R. Fletcher, Benno M. Nigg Jul 2020

Can Increased Midsole Bending Stiffness Of Sport Shoes Delay The Onset Of Lower Limb Joint Work Redistribution During A Prolonged Run?, Sasa Cigoja, Jared R. Fletcher, Benno M. Nigg

ISBS Proceedings Archive

Prolonged running has been shown to result in a redistribution of positive lower limb joint work from distal to proximal joints. Running footwear with increased midsole bending stiffness (MBS) has been shown to redistribute lower limb joint work from proximal to distal joints. How increased MBS of running shoes can affect joint work redistribution during a prolonged run, however, is unknown. Therefore, the purpose of this study was to investigate if increasing the MBS of running shoes can delay the onset of positive lower limb joint work redistribution during a prolonged run. Thirteen trained male runners (current 10 km time < 44 min.) performed 10-km runs at 90% of their speed at lactate threshold (sLT) in a control and stiff shoe condition, respectively. Prolonged running resulted in a redistribution of positive lower limb joint work from distal to proximal joints in both shoe conditions. The onset of joint work redistribution, however, was delayed at the metatarsophalangeal and ankle joint when running in the stiff shoe condition. A delayed onset of lower limb joint work redistribution in the stiff condition may result in greater energy stored and returned in distal passive-elastic structures (i.e., Achilles tendon), reducing lower limb muscle work later into the prolonged run. Also, less active muscle volume would be required to perform the same total amount of positive mechanical work when running in the stiff condition because the ankle plantarflexor muscles have less volume than the knee extensor muscles. These results contribute to the notion that footwear with increased MBS likely result in lower metabolic cost, due to delays in distal to proximal lower limb joint work redistribution.

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The Effect Of Trunk Rotation On Lower Limb Kinematics During Running – Preliminary Study, Kayla C. Hordyk, Chengtu Hsieh Jul 2020

The Effect Of Trunk Rotation On Lower Limb Kinematics During Running – Preliminary Study, Kayla C. Hordyk, Chengtu Hsieh

ISBS Proceedings Archive

The purpose of this study was to examine the running kinematics such as stride length, stride rate, speed, and joint range of motion when trunk rotation was manipulated. Six female recreational runners were recruited to perform a total of nine trials of over ground running in their comfortable speed (≈ 3.31 m/s) for natural gait, restricted trunk rotation, and exaggerated trunk rotation conditions. Exaggerating trunk rotation during running resulted in greater stride length and smaller stride rate significantly when compared to natural and restricted trunk rotation conditions. Although some of the significant change of the running kinematics were observed, the …

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Energy Cost And Lower Limb Biomechanics Of Repeated Vertical Jumping At Different Contact Times, Keitaro Seki, Heikki Kyröläinen, Yasushi Enomoto Jul 2020

Energy Cost And Lower Limb Biomechanics Of Repeated Vertical Jumping At Different Contact Times, Keitaro Seki, Heikki Kyröläinen, Yasushi Enomoto

ISBS Proceedings Archive

The purpose of the present study was to examine the effects of the contact time on energy cost and lower limb biomechanics during repeated vertical jumping. Nine male Japanese distance runners jumped for three minutes on a force platform for a preferred and long contact time. Sagittal plane kinematics, ground reaction force, and electromyography (EMG) results were measured. The following results were obtained: 1) the energy cost was significantly smaller in the preferred than in long condition, 2) mechanical work of the ankle joint was significantly greater in the preferred than in long condition, 3) mechanical work of the knee …

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The Rebound Of The Body Using Running-Specific Prostheses In Unilateral Transfemoral Amputees, Hiroto Murata, Genki Hisano, Ryo Amma, Hiroshi Takemura Prof., Hiroaki Hobara Dr. Jul 2020

The Rebound Of The Body Using Running-Specific Prostheses In Unilateral Transfemoral Amputees, Hiroto Murata, Genki Hisano, Ryo Amma, Hiroshi Takemura Prof., Hiroaki Hobara Dr.

ISBS Proceedings Archive

Although the elastic bounce of the body is considered a prerequisite for running, the rebound strategy in individuals with lower extremity amputation is not well known. This study aims to investigate the rebound strategy at different running speeds in unilateral transfemoral amputees (uTFAs) wearing running-specific prostheses (RSPs). On an instrumented treadmill, eight uTFAs ran at incremental speeds (30%, 40%, 50%, 60%, 70%, and 80% of the average speed of their 100-m personal records). The rebound strategy of the unaffected and affected limbs is evaluated using the ratio of the natural frequency of the spring-mass system (fsist) to …

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Upper Extremity Motion And Sprint Running: A Farewell To Arms?, Lance Brooks, Peter G. Weyand, Kenneth P. Clark Jul 2020

Upper Extremity Motion And Sprint Running: A Farewell To Arms?, Lance Brooks, Peter G. Weyand, Kenneth P. Clark

ISBS Proceedings Archive

Despite a lack of prior research on the topic, the sport coaching community has popularized the use of arm drills for athletes with the intent to enhance sprinting performance. The purpose of this study was to identify the effect of self-restricted arm motion on sprint running velocity. Track & field athletes and team sport athletes (n=15) completed 12 30-meter sprints (six with normal arm motion, six with restricted arm motion) while radar data was collected to quantify running velocity. Using a mono-exponential function, velocity profiles were created for each trial which produced four outcome variables: vmax, amax …

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A Comparison Of A Tucked Back Somersault Between Novice And Experienced Acrobatic Gymnasts: An Inertial Measurement Approach, Eddie J. Bradley, Kristie Harrington, Chloe Tiffin Jul 2020

A Comparison Of A Tucked Back Somersault Between Novice And Experienced Acrobatic Gymnasts: An Inertial Measurement Approach, Eddie J. Bradley, Kristie Harrington, Chloe Tiffin

ISBS Proceedings Archive

The purpose of the case study was to analyse and compare the kinematics of a backward somersault in acrobatic gymnasts. Four acrobatic gymnasts aged between 8-17 years participated in the study, as two paired partnerships. Kinematic data during a backwards tucked somersault were collected using an XSens Inertial system and whole-body joint angular kinematics were compared between experienced and novice gymnasts. Findings indicate that experienced gymnast produced slightly greater knee flexion and an increased ROM through the take-off phase and a greater adduction/abduction movement during arm swing throughout the somersault. The novice gymnast produced a higher range of flexion/extension and …

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Any Olympic Jump That Women Can Do, Men Can Do Nearly 20% Better, Emily Mcclelland, Peter Weyand Jul 2020

Any Olympic Jump That Women Can Do, Men Can Do Nearly 20% Better, Emily Mcclelland, Peter Weyand

ISBS Proceedings Archive

Men clearly outperform women in events that depend on moving the body’s mass through space. However, the between-sex differences may vary with event specific mechanical demands. Existing observations suggest between-sex differences are relatively greater for jumping than running events. We tested this sytematically by comparing the top 50 performances for men and women in Olympic running (n=9) and three jumping (n=3) events over a recent 15-year period. We found that mean male–female difference across the three jumping events (17.8± 2.7%) was 1.5 times greater than the respective mean for the nine running events (11.2 ± 1.4%) examined. We conclude …

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The Local Biomechanical Analysis Of Lower Limb On Counter-Movement Jump Between Barefoot And Shod People With Different Foot Morphology, Liang Zhiqiang, Yu Jiabin, Gu Yaodong, Li Jianshe Jul 2020

The Local Biomechanical Analysis Of Lower Limb On Counter-Movement Jump Between Barefoot And Shod People With Different Foot Morphology, Liang Zhiqiang, Yu Jiabin, Gu Yaodong, Li Jianshe

ISBS Proceedings Archive

The aim of this study was to explore the kinematic variations in knee and ankle joints and the ground reaction force between habitually barefoot (HBM) and shod males (HSM) during countermovement jump. Twenty-eight males (14 HBM,14 HSM) participated in this experiment. An 8-camera Vicon motion system was used to collect the kinematic data of knee and ankle joints from 3 dimensions and the force plate was used to collect the ground reaction force in take-off phase. Results in take-off phase showed that HSM produced two peak forces to take off and showed significantly greater knee ROM in sagittal …

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