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Differences In Muscle Demand Across Take-Off Techniques In The Back Handspring Step Out In Women’S Gymnastics, Gabriella H. Small, Richard R. Neptune Jul 2024

Differences In Muscle Demand Across Take-Off Techniques In The Back Handspring Step Out In Women’S Gymnastics, Gabriella H. Small, Richard R. Neptune

ISBS Proceedings Archive

The back handspring step out (BHS) is a foundational skill in balance beam routines that can be performed using three different take-off techniques (Simultaneous Flexion, Sequential Flexion, Double-Bounce). However, it is unclear if the different techniques require different levels of muscle demand. The purpose of this study was to use modelling and simulation to quantify muscle demand across the three techniques. While there were no differences in total average muscle demand between techniques, the Sequential Flexion technique required more demand from the knee and hip flexors, while the Simultaneous Flexion and Double-Bounce techniques required more demand from the knee and …

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Where And When: Identifying Key Regions Of Overground Sprint For Horizontal Force-Velocity Profiling, Daniel Geneau, Marc Klimstra, Ming-Chang Tsai Jul 2024

Where And When: Identifying Key Regions Of Overground Sprint For Horizontal Force-Velocity Profiling, Daniel Geneau, Marc Klimstra, Ming-Chang Tsai

ISBS Proceedings Archive

The purpose of this study was to identify regions of an overground sprint trial required to accurately determine independent Horizontal Force Velocity (FV) measures. Forty-seven university aged athletes completed two separate overground sprint trials. Baseline FV metrics; theoretical maximum velocity [V_0], peak velocity [V_max], maximum power [P_max], maximum theoretical force [F_0], decrease ratio of force [DRF], and force-velocity slope [〖FV〗_slope] were calculated for each trial. Trials were then modified by systematically removing percentages of the total sprint from the beginning and end of the trial independently. FV metrics were compared at each percentage stage and compared to baseline. Results of …

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Whole-Body Coordinative Strategies Contribute To The Minimization Of Centre Of Mass Displacement In Maximal Velocity Sprinting, Chris L. Vellucci, Shawn Beaudette Jul 2024

Whole-Body Coordinative Strategies Contribute To The Minimization Of Centre Of Mass Displacement In Maximal Velocity Sprinting, Chris L. Vellucci, Shawn Beaudette

ISBS Proceedings Archive

Sprinting is a dynamic skill that requires rapid and precise postural control. This study investigates the association between frontal plane centre of mass (CoM) displacement, whole-body coordination, and sprint velocity. Significant correlations with sprint velocity were found between stance phase frontal plane (cPL), superior inferior range of motion (SI ROM), and sprint velocity. Spatiotemporal coordinative coupling of the bilateral knees and thorax-pelvis axial twisting displayed significant partial correlations with the minimization of frontal plane cPL and SI CoM RoM. The findings of this work suggest that both the upper and lower body contribute to the control of the CoM within …

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Correlation Between Laboratory And Field Core Stability Tests And Their Link With Performance And Acl Injury Risk, Théo Weber, Guillaume Mornieux, Raphaël Jacquot, Gérôme Gauchard, Youri Duchene Jul 2024

Correlation Between Laboratory And Field Core Stability Tests And Their Link With Performance And Acl Injury Risk, Théo Weber, Guillaume Mornieux, Raphaël Jacquot, Gérôme Gauchard, Youri Duchene

ISBS Proceedings Archive

The purpose of this study was to identify the most relevant field tests for assessing core stability components and performance and injury risk. National-level women handball players (n=14) performed core stability tests in laboratory and field conditions. Moreover, their athletic performance and ACL injury risk were assessed. CKCUEST was explained by flexibility and endurance component of core stability. Shooting speed was correlated with force, flexibility and endurance, while jumping height was linked to flexibility. Positive correlation was found between ACL injury risk and core strength. These findings could help trainers to select more discriminant tests to evaluate their athletes.

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An Emg Preprocessing Pipeline And A Gui For Paralympic Cross-Country Skiing Sitting Position Assessment, Hatim Barioudi, Leonie Hirsch, Dominic Wintergerst, Ralf Rombach, Walter Rapp, Thomas Felderhoff, Natalie Mrachacz-Kersting Jul 2024

An Emg Preprocessing Pipeline And A Gui For Paralympic Cross-Country Skiing Sitting Position Assessment, Hatim Barioudi, Leonie Hirsch, Dominic Wintergerst, Ralf Rombach, Walter Rapp, Thomas Felderhoff, Natalie Mrachacz-Kersting

ISBS Proceedings Archive

An efficient sitting position and the sledge design are crucial for the success of para-athletes in cross-country sit skiing. However, there is a lack of studies on the effects of sitting positions on the performance of para-athletes. This study introduces an EMG preprocessing pipeline and a GUI to analyse and compare muscle activation in different sitting positions, as well as identify key factors to quantify the optimal sitting position. As desired by the coaches, this provides the opportunity to compare muscle activation during different sitting positions and conditions immediately after measurements. Test measurements were conducted with non-disabled athletes to validate …

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Impact Of Footwear Bending Stiffness And Torsional Stiffness On Ankle Biomechanics During Handball Specific Fake-And-Cut Manoeuvres, Timo Bagehorn, Kevin Bill, Patrick Mai, Tron Krosshaug, Uwe Kersting Jul 2024

Impact Of Footwear Bending Stiffness And Torsional Stiffness On Ankle Biomechanics During Handball Specific Fake-And-Cut Manoeuvres, Timo Bagehorn, Kevin Bill, Patrick Mai, Tron Krosshaug, Uwe Kersting

ISBS Proceedings Archive

In this study, the impact of footwear bending stiffness on ankle and foot biomechanics during indoor fake-and-cut manoeuvres was investigated. Footwear, along with torsional and bending stiffness, are hypothesized to influence the risk of ankle sprain injury. In this study, a mobile, pneumatically driven cantilever rig was used to quantify these footwear characteristics. Following this, participants executed fake-and-cut movements wearing their habitual footwear, while motion capture and force plate data were recorded. Utilizing machine learning clustering algorithms, participants were grouped based on their footwear stiffness. Subsequent SPM analysis revealed lower forefoot dorsiflexion and increased forefoot inversion in the stiff group. …

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The Foot Strike Angle Predicts Three-Dimensional Knee Joint Moments In Preplanned And Unplanned Sidestep Cuts, Kevin Bill, Patrick Mai, Tron Krosshaug, Uwe G. Kersting Jul 2024

The Foot Strike Angle Predicts Three-Dimensional Knee Joint Moments In Preplanned And Unplanned Sidestep Cuts, Kevin Bill, Patrick Mai, Tron Krosshaug, Uwe G. Kersting

ISBS Proceedings Archive

This study investigated if knee joint moments are related to the foot strike angle in preplanned and unplanned handball-specific sidestep cuts performed by n = 51 female handball players. Canonical correlation analysis (CCA) with the foot strike angle as predictor variable was performed on the knee joint moment vector field (Mxyz). Subsequently, post-hoc tests using CCA for moment couples and linear regression for individual moment components were performed. In both conditions, the foot strike angle was related to Mxyz. However, the relationship remains partially unexplained when the three-dimensionality of the moment vector remains unaccounted for, especially …

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Analysis Of Kinematics During Sprint Running And Different Types Of Jumps, Bjørn Johansen, Roland Van Den Tillaar Jul 2024

Analysis Of Kinematics During Sprint Running And Different Types Of Jumps, Bjørn Johansen, Roland Van Den Tillaar

ISBS Proceedings Archive

This study aimed to compare sprint running and various horizontal jumps in terms of speed and step kinematics, focusing on speed versus distance and their relationship with maximal running speed. Twelve female sprinters performed sprints, single-leg jumps for distance and speed, and bounding for distance and speed. The findings showed significant differences in kinematics between sprinting and jumping. Positive correlations were found between sprint speed and single-leg jump speed and distance, step length in all jumps, and contact and flight time in some. No significant correlation was found between sprint speed and step frequency in the jumps. Bounding for speed …

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Estimating Joint Moments During Treadmill Running Using Various Consumer Based Wearable Sensor Locations, Josh Autton Carter, Xi Chen, Dario Cazzola, Grant Trewartha, Ezio Preatoni Jul 2024

Estimating Joint Moments During Treadmill Running Using Various Consumer Based Wearable Sensor Locations, Josh Autton Carter, Xi Chen, Dario Cazzola, Grant Trewartha, Ezio Preatoni

ISBS Proceedings Archive

We estimated lower limb sagittal plane joint moments during treadmill running using wearable sensors and different commonly used locations. We compared outcomes from supervised recurrent neural network machine learning (ML) models to criterion values from motion capture and inverse dynamics. The normalised root mean squared error between outcomes from the ML model fed with the entire wearable dataset (pressure insoles and inertial measurement units at the foot, wrist, T10, and sacrum) was 8.9%, 13.5%, and 18.2% for the ankle, knee, and hip joint respectively. Removal of any two upper body sensors did not decrease the accuracy of the estimations. This …

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The Impact Of Ground Reaction Force Variables On Bend Sprint Running Performance, Jonathan White, Joseph Moore, Hans Von Lieres Und Wilkau, Gareth Irwin, Cassie Wilson, Timothy Exell Jul 2024

The Impact Of Ground Reaction Force Variables On Bend Sprint Running Performance, Jonathan White, Joseph Moore, Hans Von Lieres Und Wilkau, Gareth Irwin, Cassie Wilson, Timothy Exell

ISBS Proceedings Archive

This study aimed to investigate force production and highlight kinetic variables that relate to bend sprinting performance. Eight competitive sprinters undertook three 60 m sprints around a 36.5 m bend radius. Paired t-tests were run using statistical parametric mapping to compare the left and right stance phases. Pearson correlation coefficients were calculated to assess the relationships between step velocity (SV) and kinetic variables. Significantly greater vertical and inward force was produced during early right stance compared to left. Left inward force was significantly greater than left during mid and late stance. Only braking durations were significantly negatively correlated to SV. …

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Development And Recommendation Of Kinematic Event Detection Methods For Use During Bend Sprint Running, Jonathan White, Cassie Wilson, Gareth Irwin, Hans Von Lieres Und Wilkau, Joseph Moore, Timothy Exell Jul 2024

Development And Recommendation Of Kinematic Event Detection Methods For Use During Bend Sprint Running, Jonathan White, Cassie Wilson, Gareth Irwin, Hans Von Lieres Und Wilkau, Joseph Moore, Timothy Exell

ISBS Proceedings Archive

This study aimed to validate different kinematic event detection methods for use during maximal velocity bend sprint running. Eight sprinters completed nine 60 m bend sprints each around an athletic track with a 36.5 m bend radius. Three kinematic event detection methods were adapted and compared to instances of touchdown and toe-off as determined by force plates. Using peak and maximum vertical acceleration of the toe marker yielded mean errors of less than 1 frame (0.004 s) for touchdown, whilst peak acceleration was the most accurate for determining toe off (mean error = 0.85 frame).The findings suggest that, when carefully …

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Towards Real-Time Assessment: Wearable-Based Estimation Of 3d Knee Kinetics In Running And The Influence Of Preprocessing Workflows, Lucas Höschler, Christina Halmich, Christoph Schranz, Julian Fritz, Anne Koelewijn, Hermann Schwameder Jul 2024

Towards Real-Time Assessment: Wearable-Based Estimation Of 3d Knee Kinetics In Running And The Influence Of Preprocessing Workflows, Lucas Höschler, Christina Halmich, Christoph Schranz, Julian Fritz, Anne Koelewijn, Hermann Schwameder

ISBS Proceedings Archive

This study aimed to estimate knee kinetics in recreational runners during treadmill running based on seven IMUs and pressure insoles using convolutional neural networks (CNN) with two input segmentations. Ground-truth knee moments of 19 runners during sloped and level treadmill running were calculated by conventional lab-based methods. We trained two CNNs on (1) step-segmented and (2) continuously windowed inputs and investigated differences in their joint moment estimations to ground-truth calculations. For both input segmentations, the predictions errors (nRMSE) were below 0.10 and 0.25 for the sagittal and non-sagittal planes, respectively. The continuous inputs led to a slightly decreased accuracy during …

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Exploring The Performance – Acl Injury Risk Conflict During Anticipated And Unanticipated Sidestepping Tasks, Youri Duchene, Nicolas Charles Hanen, Léo Banet, Guillaume Mornieux Jul 2024

Exploring The Performance – Acl Injury Risk Conflict During Anticipated And Unanticipated Sidestepping Tasks, Youri Duchene, Nicolas Charles Hanen, Léo Banet, Guillaume Mornieux

ISBS Proceedings Archive

The aims of this study were i) to determine if performing regression models with high-risk datasets compared to full datasets could help to understand better which biomechanical variables could really be considered ‘at-risk’ and/or ‘better for performance’ and ii) to determine the effect of anticipation on ‘at-risk’ biomechanical variables. Basketball players (n=33) completed 6 changes of direction in anticipated or unanticipated conditions. Kinematics, dynamics and performance were measured with motion capture and force plates. A lower number of predictors were found for high-risk dataset compared to full dataset. Hip adduction and trunk lateral lean could be both considered ‘at-risk’ and …

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Comparison Of Discrete (0d) And Continuous (1d) Analysis Of Sidestep Cutting Kinematics And Kinetics, Eline M. Nijmeijer, Matthias Kempe, Marije T. Elferink-Gemser, Anne Benjaminse Jul 2024

Comparison Of Discrete (0d) And Continuous (1d) Analysis Of Sidestep Cutting Kinematics And Kinetics, Eline M. Nijmeijer, Matthias Kempe, Marije T. Elferink-Gemser, Anne Benjaminse

ISBS Proceedings Archive

Although both discrete (0D) and continuous (1D) analysis are used, the differences in results between both analyses in repeated measures designs are unclear. Therefore, the purpose of this study was to compare the results of a discrete and continuous analysis on the same dataset. Data of an intervention study regarding sidestep cutting with two groups and three sessions of measurements were used. Analyses of mean and peak values (0D) and timeseries (1D) revealed contradictory results for some variables. More interestingly, the direction of the results was different sometimes. This substantiates the impact that an analysis method can have on data …

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Variability Of Sagittal Joint Kinematics Of Female Horse-Riders Over A Jump., Rafaelle Baby, Celeste Wilkins Dr, Laurence Protheroe Dr, Russell Mackechnie-Guire Dr, Kathryn Nankervis Dr Jul 2024

Variability Of Sagittal Joint Kinematics Of Female Horse-Riders Over A Jump., Rafaelle Baby, Celeste Wilkins Dr, Laurence Protheroe Dr, Russell Mackechnie-Guire Dr, Kathryn Nankervis Dr

ISBS Proceedings Archive

This study aimed to improve understanding of horse-rider technique in show jumping, to support the development of training programs. Range of motion, peak flexion and extension angles were estimated for the shoulder, elbows, hips, knees, and ankles of six female riders jumping two different fence types (oxer and straight), using a full-body inertial motion unit (IMU) suit (MVN Awinda). Horse kinematics were recorded using IMU and GPS technology (Alogo Move Pro). All rider joints showed inter-participant (population standard deviation range: 5.4°(ankle) - 43.2° (elbow)) and intra-participant variability (individual SD range: 1.7°(ankle) - 57.5°(hips)). Findings suggest differences in riding strategies and/or …

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Speed-Dependent Increase In Lumbar Lordosis Is Inconsistent With Speed-Independent Pelvic Tilt During Treadmill Running, Tempei Tominaga, Yoshiki Tasaki, Natsuki Sado Jul 2024

Speed-Dependent Increase In Lumbar Lordosis Is Inconsistent With Speed-Independent Pelvic Tilt During Treadmill Running, Tempei Tominaga, Yoshiki Tasaki, Natsuki Sado

ISBS Proceedings Archive

Lumbar lordosis (LL) is considered as an important factor of low back pain. Although LL during running (dynamic LL) and anterior pelvic tilt (APT) are thought to increase simultaneously, this relationship has not been examined when running speed is changed. Here we show that dynamic LL increases with the increase in running speed, whereas APT is invariant during treadmill running at 4.0, 5.5, 7.0 and 8.5 m/s in 18 male collegiate athletes. The speed-dependent increase in dynamic LL suggests that runners and coaches should be cautious that greater mechanical load on the lumbar spine might occur during faster running. The …

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The Relationships Of Functional Mobility With Muscle Strength And Proprioception Among Older Adults, Qi Wang Miss, Yanhao Liu, Qipeng Song, Dewei Mao, Xinrui Zhang Jul 2024

The Relationships Of Functional Mobility With Muscle Strength And Proprioception Among Older Adults, Qi Wang Miss, Yanhao Liu, Qipeng Song, Dewei Mao, Xinrui Zhang

ISBS Proceedings Archive

Functional mobility impairment is the most common risk factor for falls among older adults, with three potential factors (muscle strength, tactile sensation, and proprioception) being responsible for their functional mobility. This study aims to compare functional mobility and the three factors, and investigate their relationships among older adults of different ages. One hundred sixty-six participants were categorized into younger (YG), middle (MG), or older (OG) aged groups. The OG has worse functional mobility, muscle strength, tactile sensation, and proprioception than YG and MG. In the YG and MG groups, both proprioception and muscle strength showed correlations with functional mobility. In …

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Associations Between Strength And Power With Throwing Performance In High Level Male And Female Javelin Throwers, Miika Köykkä, Johanna K. Ihalainen, Anssi Saari, Benjamin Waller, Neil J. Cronin Jul 2024

Associations Between Strength And Power With Throwing Performance In High Level Male And Female Javelin Throwers, Miika Köykkä, Johanna K. Ihalainen, Anssi Saari, Benjamin Waller, Neil J. Cronin

ISBS Proceedings Archive

This study investigated the associations between strength and power measures and estimated javelin throwing performance. Thirteen male (personal best: 77.0 ± 5.7 m) and thirteen female (55.8 ± 5.8 m) javelin throwers underwent various lower and upper body power and strength tests, along with a javelin throwing test. Associations with throwing performance were observed for lower body power measures in males and upper and lower body maximal strength in females, suggesting sex-specific differences in important physical characteristics for throwing.

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Differences Between Parallel Skiing And Carving Based On Wearable Sensor Data And Technique Analysis Algorithms, Daniel Debertin, Anna Wargel, Michael Böhmer, Peter Federolf Jul 2024

Differences Between Parallel Skiing And Carving Based On Wearable Sensor Data And Technique Analysis Algorithms, Daniel Debertin, Anna Wargel, Michael Böhmer, Peter Federolf

ISBS Proceedings Archive

The purpose of this study was to objectively identify differences between conventional parallel skiing (side-skidding) and carving (no side-skidding) with regard to selected movement actions of the upper body and their influences on movement stability. Comparison of the two skiing styles is approached by a set of quantifiable technique metrics (lateral, horizontal and rotational movement of the upper body), extracted as principal components (PCs) from whole-body wearable sensor data of highly experienced skiers (n=20). Stability was quantified through normalized jerk scores. Carving involved increased angulation of the hip in the transition phase, a more posterior body posture over the whole …

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The Effect Of Surfaces On The Knee Biomechanics Of A 90 Degree Cut, Samantha Rhodes, Richard Jones, Lee Herrington, Chris Bramah Jul 2024

The Effect Of Surfaces On The Knee Biomechanics Of A 90 Degree Cut, Samantha Rhodes, Richard Jones, Lee Herrington, Chris Bramah

ISBS Proceedings Archive

Assessments following anterior cruciate ligament (ACL) injuries are commonly on surfaces that do not represent the playing or training surface. This study aimed to investigate how different surfaces, specifically a running track and artificial grass, influence biomechanics during a 90-degree change of direction (COD). Seventeen participants performed a 90-degree COD on both a running track surface and an artificial grass surface. Motion capture and force plate data were collected. No significant differences were observed in kinematic variables between surfaces. However, the knee extensor moment and posterior braking force were significantly higher on the running track compared to artificial grass (P

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On-Court Mechanical Work Measured Using Markerless Motion Capture Is Associated With Acute Fatigue In Tennis, Julie Emmerson, Laurie Needham, Murray Evans, Sean Williams, Steffi Colyer Jul 2024

On-Court Mechanical Work Measured Using Markerless Motion Capture Is Associated With Acute Fatigue In Tennis, Julie Emmerson, Laurie Needham, Murray Evans, Sean Williams, Steffi Colyer

ISBS Proceedings Archive

Measurement of mechanical work with a markerless motion capture system was assessed for the application of training ‘load’ monitoring. Four tennis players completed an on-court fatiguing protocol interspersed with sprint tests, with relationships between reduction in sprint velocity and internal and external mechanical work done tested. Repeated measures correlations for total and external mechanical work, and external mechanical work estimated from centre of mass proxies (pelvis and mid-hip) were comparable and ranged from -0.89 to -0.86. Whilst the calculated work done varied greatly between the methods (~42% for pelvis), all showed a strong relationship with fatigue and could provide insight …

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Real-Time Biofeedback To Control Trunk Power Production In Ergometer Rowing, Lorenzo Pitto, Frederic Simon, Leo Banet, Geoffrey Ertel, Guillaume Mornieux Jul 2024

Real-Time Biofeedback To Control Trunk Power Production In Ergometer Rowing, Lorenzo Pitto, Frederic Simon, Leo Banet, Geoffrey Ertel, Guillaume Mornieux

ISBS Proceedings Archive

The purpose of this study was to test a real-time feedback for ergometer rowing based on parameters describing a rower’s technique, specifically the curve of the power produced by the trunk. The goal was to enhance the trunk engagement during the drive phase. Eleven rowers performed an ergometer rowing session at 20spm and maximum intensity, where their habitual technique was measured. Then, they performed six sessions of 3min with feedback exposure on trunk time to peak power and work ratio. On average, rowers were able to advance their trunk power production within the drive phase by 1.3%, but without significant …

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Unraveling Kinematics Of Unplanned Change-Of-Direction Maneuvers: A Field-Based Exploration Focused On Acl Injury Risk, Mareike Kühne, Christian Sanin, Maurice Mohr Jul 2024

Unraveling Kinematics Of Unplanned Change-Of-Direction Maneuvers: A Field-Based Exploration Focused On Acl Injury Risk, Mareike Kühne, Christian Sanin, Maurice Mohr

ISBS Proceedings Archive

ACL injury risk during COD maneuvers is dependent on the chosen movement pattern, which can be impacted by factors like anticipation. This study used a field-based approach including multiple COD angles and directions to explore the effects of anticipation and COD angle on joint angles at the initial ground contact. Twenty soccer players completed planned and unplanned CODs, with kinematic data collected by IMU sensors. For unplanned scenarios, we found evidence for risk-mitigating adaptations (higher knee flexion (p < .001), lower hip abduction (p = 0.046)) as well as injury-provoking movements (less pelvis pre-orientation (p < .001), higher trunk rotation (p = 0.016)), which resulted in decreased COD …

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The Timing Of Stomping (Fumikomi) In Kendo Attacks: Comparison Of Kyu And Dan Level Kendokas, Kwangyul Jeong, Franz Konstantin Fuss Jul 2024

The Timing Of Stomping (Fumikomi) In Kendo Attacks: Comparison Of Kyu And Dan Level Kendokas, Kwangyul Jeong, Franz Konstantin Fuss

ISBS Proceedings Archive

According to the doctrine of Kendo, spirit, sword, and body must be synchronized. This principle also applies to the timing of stomping when striking the head target. We instrumented a right Kendo sock and a Kendo helmet (head gear) with piezoresistive sensors, and measured the time interval Δt between two impacts, stomping and striking the head target, in 16 Kendokas (6 Kyu and 10 Dan holders). Δt was significantly (p < 0.0001) different in Kyu and Dan holders, with medians of –0.040 s (stomping before striking) and +0.502 s (stomping after striking) respectively, indicating that the two impacts were not synchronised. This study proposes to revise the doctrines of Kendo and accept the fact that in Dan holders, the foot impact on the ground occurs on average 0.5 s after striking the head target.

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Effects Of Half-Marathon Running On Quadriceps And Hamstring Torque, Wenjin Wang, Marvin Zedler, Yutong Jing, Wolfgang Potthast Jul 2024

Effects Of Half-Marathon Running On Quadriceps And Hamstring Torque, Wenjin Wang, Marvin Zedler, Yutong Jing, Wolfgang Potthast

ISBS Proceedings Archive

This study aims to investigate changes in concentric and eccentric quadriceps and hamstring torque following half-marathon running on the treadmill. Thirty-eight recreational runners participated in this study. Isokinetic dynamometry measured torque before, 5 minutes, 24 and 48 hours after completing half-marathon. A significant decrease in concentric and eccentric torque were observed at 5 minutes after a half-marathon for both hamstrings (all p < 0.001) and quadriceps (all p < 0.001), with recovery evident within 24 hours. However, 48 hours after the half-marathon, individuals exhibited increased concentric hamstrings torque (p=0.034) and eccentric quadriceps (p=0.002) compared to the baseline. Running a half-marathon may increase the risk of running injuries. However, these effect were transient, with torque levels returning to baseline within 24 hours.

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Developing A New Performance Measure To Quantify The Difference Between Actual And Predicted On-Water Rowing Performance, Sam Jones, Chris Bailey, Dave Thomas, Mark G. E. White, Paul Rees, Huw D. Summers, Neil E. Bezodis Jul 2024

Developing A New Performance Measure To Quantify The Difference Between Actual And Predicted On-Water Rowing Performance, Sam Jones, Chris Bailey, Dave Thomas, Mark G. E. White, Paul Rees, Huw D. Summers, Neil E. Bezodis

ISBS Proceedings Archive

This study developed a measure of on-water rowing performance (on-water delta) that quantifies the difference between actual on-water performance and on-water performance as predicted from ergometer performance. Maximal effort 2000 m ergometer and on-water times (n = 340) were collected from 162 athletes over a 16-year period. A linear mixed model was fitted to the dataset to enable predictions of on-water performance from ergometer performance whilst accounting for repeated measures and other factors such as potential environmental effects. On-water delta was defined as a model residual and ranged from -32.8 s (overperformed) to 51.1 s (underperformed). On-water …

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On-Field Assessment Of Change-Of-Direction (Cod) Movements: Adaptation In Leg And Trunk Posture Throughout A Cod Sequence, Maurice Mohr, Christian Sanin, Mareike Kühne Jul 2024

On-Field Assessment Of Change-Of-Direction (Cod) Movements: Adaptation In Leg And Trunk Posture Throughout A Cod Sequence, Maurice Mohr, Christian Sanin, Mareike Kühne

ISBS Proceedings Archive

This study investigated adaptations in change-of-direction (COD) movement strategies throughout a sequence of maximum-speed CODs in an on-field testing scenario that involved complex decision making and limited time for motor preparation. Twenty soccer players completed randomized sequences of pre-planned and unplanned 45°-135° CODs and their joint movements were tracked using inertial measurement units. For 90°-135° turns, the last vs. first CODs showed a more extended knee and rotated trunk at initial contact. These kinematic features may reflect insufficient time to prepare for the ground contact of a COD that immediately follows a previous COD and are more consistent with postures …

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The Effect Of The Difference In Resistance Training Velocity Loss On Muscular Strength And Explosive Performance, Chenfu Huang, Li-Fu Cheng Jul 2024

The Effect Of The Difference In Resistance Training Velocity Loss On Muscular Strength And Explosive Performance, Chenfu Huang, Li-Fu Cheng

ISBS Proceedings Archive

The present study aimed to compare the effects of mixed-training with different proportions of concentric velocity loss (10% vs. 30%) on muscular strength and explosive performance. Twenty healthy trained men were recruited and randomly assigned to the velocity loss of 10% (VL10) and velocity loss of 30% (VL30) for eight weeks of mixed-training. The participants performed 1RM in back squat, countermovement jump (CMJ), 10-m (T10) and 20-m (T20) sprint running before and after mixed-training. Both groups showed similar improvement in the 1RM strength (9.6% vs 9.3%). However, only the VL10 group significantly improved CMJ (6.2%), T10 (-1.7%), and T20 (-1.3%) …

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The Influence Of Lower Limb Muscle Pre-Activation On Knee Joint Dynamic Control During A Single-Leg Landing Task In Badminton, Pingping Zhu, Yanjia Xu Wang, Yanjia Xu, Zhe Hu Jul 2024

The Influence Of Lower Limb Muscle Pre-Activation On Knee Joint Dynamic Control During A Single-Leg Landing Task In Badminton, Pingping Zhu, Yanjia Xu Wang, Yanjia Xu, Zhe Hu

ISBS Proceedings Archive

Purpose: Lower limb neuromuscular strategies impact knee biomechanics, crucial for ACL injury prevention. Yet, the link between them remains unclear. In our randomized trial with 34 badminton players, we examined lower limb muscle preactivity during single-leg landings. Findings revealed that increased rectus femoris preactivation correlated with heightened knee valgus angle. Moreover, higher lateral hamstring/quadriceps co-contraction ratios predicted increased knee extension moments. These outcomes suggest potential benefits in ACL injury prevention through reduced quadriceps pre-activation and optimal lateral hamstring/quadriceps co-contraction ratios. Understanding these relationships aids in developing targeted prevention strategies for anterior cruciate knee injuries.

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Analysis Of Men's Professional Tennis Singles Match Data And Strategies - A Case Study Of 2022 And 2023 Atp Year-End Finals, Chia-Hao Li, Chen-Fu Huang, Jia-Hao Chang Jul 2024

Analysis Of Men's Professional Tennis Singles Match Data And Strategies - A Case Study Of 2022 And 2023 Atp Year-End Finals, Chia-Hao Li, Chen-Fu Huang, Jia-Hao Chang

ISBS Proceedings Archive

This study analyzed serve and serve return performance in the 2022 and 2023 ATP Year-End Tennis Championships, focusing on player rankings. The post-match data is compared between the top and bottom 4 players, examining differences in the top 4 rankings for both 2022 and 2023. Two-way ANOVA was used to examine the differences in "service and serve return " across different years and rankings, with a significance level set at α =.05. The key factors for winning in tennis include serve speed, average second serve speed, and scoring rates on both first and second serves. Top 4 ranked players achieved …

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