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  1. 16 Journal of Human Kinetics

  2. 6 Human Movement

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  1. 6 Sinclair J.

  2. 5 Taylor P. J.

  3. 4 Hobbs S. J.

  4. 3 Tillaar R. v. d.

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1
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Methods of Determining Hip Joint Centre: Their Influence on the 3-D Kinematics of the Hip and Knee During the Fencing Lunge

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Sinclair J., Bottoms L.
Human Movement
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2013
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vol. 14
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issue 3
229-237
EN
Purpose. The lunge is a fundamental offensive fencing technique, common to all contemporary fencing styles. Therefore, when using 3-D kinematic analysis to quantify lower extremity rotations during the fencing lunge, it is important for researchers to correctly interpret this movement. Locating the centre of the hip is required to accurately quantify hip and knee joint rotations, with three non-invasive techniques using anatomical, functional and projection methods currently available for the estimation of hip joint centre. This study investigated the influence of these three techniques on hip and knee joint kinematics during the fencing lunge. Methods. Three-dimensional kinematics of the lunge were collected from 13 experienced epee fencers using an eight-camera motion capture system. The 3-D kinematics of the lunge were quantified using the three hip joint centre estimation techniques. Repeated measures ANOVAs were used to compare the discrete 3-D kinematic parameters, and intra-class correlations were employed to identify similarity across the 3-D kinematic waveforms from the three techniques. Results. The results indicate that whilst the kinematic waveforms were similar (R2 ≥0.96); significant differences in discrete parameters were also evident at both the hip and knee joint in the coronal and transverse planes. Conclusions. It appears based on these observations that different hip joint centre locations can significantly influence the resultant kinematic parameters and cannot be used interchangeably.
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Influence of Different Hip Joint Centre Locations on Hip and Knee Joint Kinetics and Kinematics During the Squat

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Sinclair J., Atkins S., Vincent H.
Journal of Human Kinetics
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2014
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vol. 44
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issue 1
5-17
EN
Identification of the hip joint centre (HJC) is important in the biomechanical examination of human movement. However, there is yet to be any published information regarding the influence of different HJC locations on hip and knee joint kinetics during functional tasks. This study aimed to examine the influence of four different HJC techniques on 3- D hip and knee joint kinetics/kinematics during the squat. Hip and knee joint kinetics/kinematics of the squat were obtained from fifteen male participants using an eight camera motion capture system. The 3-D kinetics/kinematics of the squat were quantified using four hip joint centre estimation techniques. Repeated measures ANOVAs were used to compare the discrete parameters as a function of each HJC location. The results show that significant differences in joint angles and moment parameters were evident at both the hip and knee joint in the coronal and transverse planes. These observations indicate that when calculating non-sagittal joint kinetics/kinematics during the squat, researchers should carefully consider their HJC method as it may significantly affect the interpretation of their data.
3
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Breast Support Garments are Ineffective at Reducing Breast Motion During an Aqua Aerobics Jumping Exercise

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Mills C., Ayres B., Scurr J.
Journal of Human Kinetics
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2015
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vol. 46
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issue 1
49-58
EN
The buoyant forces of water during aquatic exercise may provide a form of ‘natural’ breast support and help to minimise breast motion and alleviate exercise induced breast pain. Six larger-breasted females performed standing vertical land and water-based jumps, whilst wearing three breast support conditions. Underwater video cameras recorded the motion of the trunk and right breast. Trunk and relative breast kinematics were calculated as well as exercised induced breast pain scores. Key results showed that the swimsuit and sports bra were able to significantly reduce the superioinferior breast range of motion by 0.04 and 0.05 m, respectively, and peak velocity by 0.23 and 0.33 m/s, respectively, during land-based jumping when compared to the bare-breasted condition, but were ineffective at reducing breast kinematics during water-based jumping. Furthermore, the magnitude of the swimsuit superioinferior breast range of motion during water-based jumping was significantly greater than land-based jumping (0.13 m and 0.06 m), yet there were no significant differences in exercise induced breast pain, thus contradicting previously published relationships between these parameters on land. Furthermore, the addition of an external breast support garment was able to reduce breast kinematics on land but not in water, suggesting the swimsuit and sports bras were ineffective and improvements in swimwear breast support garments may help to reduce excessive breast motion during aqua aerobic jumping exercises.
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The Existence of a Sticking Region in Free Weight Squats

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Tillaar R. v. d., Andersen V., Saeterbakken A. H.
Journal of Human Kinetics
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2014
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vol. 42
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issue 1
63-71
EN
The aim of this study was to investigate the existence of the sticking region in two legged free weight squats. Fifteen resistance-training males (age 24 ± 4 years, body mass 82 ± 11 kg, body height 179 ± 6 cm) with 6 ± 3 years of resistance-training experience performed 6-RM in free weight squats. The last repetition was analyzed for the existence of a sticking region. Only in 10 out of 15 participants a sticking region was observed. The observed sticking region was much shorter than in the bench press. Furthermore, rectus femoris decreased the EMG activity in contrast to increased EMG activity in biceps femoris around the sticking and surrounding region. No significant change in EMG activity was found for the lateral and medial vastus muscles. It is suggested that a combination of these muscle activity changes could be one of the causes of the existence of the sticking region in free weight squats
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Kinematic Adaptations of Forward and Backward Walking on Land and in Water

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Cadenas-Sanchez C., Arellano R., Vanrenterghem J., López-Contreras G.
Journal of Human Kinetics
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2015
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vol. 49
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issue 1
15-24
EN
The aim of this study was to compare sagittal plane lower limb kinematics during walking on land and submerged to the hip in water. Eight healthy adults (age 22.1 ± 1.1 years, body height 174.8 ± 7.1 cm, body mass 63.4 ± 6.2 kg) were asked to cover a distance of 10 m at comfortable speed with controlled step frequency, walking forward or backward. Sagittal plane lower limb kinematics were obtained from three dimensional video analysis to compare spatiotemporal gait parameters and joint angles at selected events using two-way repeated measures ANOVA. Key findings were a reduced walking speed, stride length, step length and a support phase in water, and step length asymmetry was higher compared to the land condition (p<0.05). At initial contact, knees and hips were more flexed during walking forward in water, whilst, ankles were more dorsiflexed during walking backward in water. At final stance, knees and ankles were more flexed during forward walking, whilst the hip was more flexed during backward walking. These results show how walking in water differs from walking on land, and provide valuable insights into the development and prescription of rehabilitation and training programs.
6
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Digital Filtering of Three-Dimensional Lower Extremity Kinematics: an Assessment

100%
Sinclair J., Taylor P. J., Hobbs S. J.
Journal of Human Kinetics
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2013
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vol. 39
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issue 1
25-36
EN
Errors in kinematic data are referred to as noise and are an undesirable portion of any waveform. Noise is typically removed using a low-pass filter which removes the high frequency components of the signal. The selection of an optimal frequency cut-off is very important when processing kinematic information and a number of techniques exists for the determination of an optimal frequency cut-off. Despite the importance of cut-off frequency to the efficacy of kinematic analyses there is currently a paucity of research examining the influence of different cut-off frequencies on the resultant 3-D kinematic waveforms and discrete parameters. Twenty participants ran at 4.0 m•s-1 as lower extremity kinematics in the sagittal, coronal and transverse planes were measured using an eight camera motion analysis system. The data were filtered at a range of cut-off frequencies and the discrete kinematic parameters were examined using repeated measures ANOVA’s. The similarity between the raw and filtered waveforms were examined using intra-class correlations. The results show that the cut-off frequency has a significant influence on the discrete kinematic measure across displacement and derivative information in all three planes of rotation. Furthermore, it was also revealed that as the cut-off frequency decreased the attenuation of the kinematic waveforms became more pronounced, particularly in the coronal and transverse planes at the second derivative. In conclusion, this investigation provides new information regarding the influence of digital filtering on lower extremity kinematics and re-emphasizes the importance of selecting the correct cut-off frequency.
7
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Sex Differences in Tibiocalcaneal Kinematics

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Sinclair J., Taylor P. J.
Human Movement
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2014
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vol. 15
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issue 2
105-109
EN
Purpose. Female runners typically suffer more from chronic running injuries than age-matched males, although the exact biome-chanical mechanisms behind the increased susceptibility of female runners are unknown. This study aimed to compare sex differences in tibiocalcaneal kinematics during the stance phase of running. Methods. Twenty male and twenty female participants ran at 4.0 m · s–1. Tibiocalcaneal kinematics were measured using an eight-camera motion analysis system and compared using independent samples t tests. Results. Peak eversion and tibial internal rotation angles were shown to be significantly greater in female runners. Conclusions. based on these observations, it was determined that female runners may be at increased risk from chronic injury development in relation to excessive tibiocalcaneal motions in the coronal and transverse planes.
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Biomechanical Differences Associated with Two Different Load Carriage Systems and their Relationship to Economy

100%
Lloyd R., Cooke C.
Human Movement
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2011
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vol. 12
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issue 1
65-74
EN
Purpose. To explore relationships between load carriage economy and the kinematics and kinetics of load carriage using both a backpack (BP) and a double pack (DP). Basic procedures. Nine participants walked on a treadmill at gradients of between 27% downhill and 20% uphill, and over a force plate on level ground, at a speed of 3 km.h-1. Expired air was collected throughout the treadmill experiment and all experiments were filmed for subsequent biomechanical analysis. The relative economy of load carriage was expressed in terms of the Extra Load Index (ELI). Main findings. There was a tendency for the double pack system to be associated with better economy than the BP. The double pack system provoked significantly less forward lean than the backpack and the horizontal displacement of the CoM was also smaller for the double pack system and both of these factors were strongly related to economy. There was, however, a greater range of motion of the trunk in the DP condition and this was also associated with improved economy. Conclusions. The results suggest that the DP was associated with smaller perturbations in gait than the BP and that this represents an advantage in terms of economy. In particular freedom of movement of the trunk in the sagittal plane may be an important consideration in the efficiency of load carriage systems.
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Kinematic regulation of time and frequency domain components of accelerations measured at the tibia during heel-toe running

100%
Sinclair J., Taylor P. J., Hobbs S. J.
Human Movement
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2014
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vol. 15
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issue 1
51-55
EN
Purpose. The transmission of tibial accelerations through the musculoskeletal system may contribute to the aetiology of injuries. Therefore, determining the mechanisms that regulate impact accelerations may have potential clinical significance. This study aimed to determine the influence of lower extremity kinematics on the regulation of both time and frequency domain characteristics of tibial accelerations during running. Methods. Forty participants ran at 4.0 m · s-1 ± 5%. Three-dimensional joint kinematics from the hip, knee and ankle were measured using an eight-camera motion analysis system operating at 250 Hz. Regression analyses treating time and frequency domain tibial acceleration parameters as criterion variables were used to identify lower extremity parameters associated with the passive regulation of impact accelerations. Results. The overall regression model yielded an adj. R2 = 0.13, p 0.01. Knee flexion velocity at footstrike was identified as a significant regulator of tibial accelerations in the time domain. No kinematic variables were identified as significantly related to the frequency domain properties of the signal. Conclusions. The findings of the current investigation suggest that sagittal plane knee flexion velocity at footstrike can regulate the magnitude of impact loading linked to the development of chronic injuries.
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Kinematics Tactics in Swimming Races on the Example of the Beijing 2008 Olympic Games and the Rome 2009 World Championships

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Lipińska P.
Baltic Journal of Health and Physical Activity
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2011
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vol. 3
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issue 4
225-236
EN
Background: Tactics in endurance disciplines is often considered by a analysis of distribution of velocity at a distance. Long-distance swimming (800m, 1500m) is a discipline perfectly located in the above definition. Thus the purpose of the paper is to deepen knowledge on sport tactics based on the distribution of velocity by athletes training swimming at the highest level.Material/Methods: The research material comprised finalists of the swimming race on the 800 meters at the Olympic Games in Beijing (2008) and the World Championships in Rome (2009). Data on the average speed for the entire distance and average speed for the 50-meter segments were analyzed. The average speed for the "halves" (350m and 400m) and "quarters" (150m, 200m, 200m, 200m) was calculated, and the specific "velocity differences index" was also identified (VDI). To illustrate the results better, a linear and non-linear regression equation was used.Results: The results show that the top athletes both of the Beijing Olympics and the World Championships in Rome maintain consistency of the pace; deviations from the average velocity are low, and increasing speed happens at the finish. The analysis of non-linear regression equation confirms this observation. The second "half" of the distance is covered by the best swimmer at higher speeds compared to the first part of the distance; the analysis of "quarters" indicates that the middle one is the slowest. The values of VDI for "halves" have the lowest values in both races for the best swimmers.Conclusions: The analysis of results justifies the conclusion that primarily it is the constant pace of the race that gives a chance to obtain a high result. The ultimate way in which the race is to be executed depends on athlete's individual predispositions; however, maintaining a constant high speed without speeding up at the finish proved to be an effective tactic in the case of one of the top athletes in both races.
11
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Content available

Kinematic analysis of the kick start from OSB12

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Matúš I., Kandráč R.
Physical Activity Review
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2020
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vol. 2
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issue 8
86-96
EN
Introduction: Start performance in swimming plays a major role in determining the final standings, especially in sprint races. The purpose of the study was to determine kinematic parameters underlying the kick start from OSB12 in terms of the kick plate position and shoulder positioning at the start. Material and methods: The sample included 8 non-randomly recruited performance-level swimmers whose average age, body height, and body weight was 17.4 ± 1.8 years, 182.2 ± 3.4 cm and 81.00 ± 3.9 kg, respectively. To measure the kinematic parameters, we used the SwimPro camera system. The parameter rs measured included angular parameters and kinematic parameters for each of the start phases: block phase, flight phase, and water phase. We processed the collected biomechanical data using the Statistica 12.0 software. To determine significant differences between the kick plate positions in three types of start, we applied the Mann-Whitney U test. Results: We found significant differences (p<0.05) in the selected kinematic parameters in all phases, which depended on the OSB12 kick plate position and basic starting position (front-, neutral-, and rear-weighted). The greatest differences in the parameters measured were found between the front-weighted start and rearweighted start. We may conclude that performance-level swimmers should adjust the rear kick plate to positions 3 and 4 and assume the following starting position: front knee angle between 131° and 133°, rear knee angle around 80°, and trunk angle between 40° and 41°. This starting position affects the flight phase, namely takeoff angle (40⁰-41⁰), head position at takeoff (1.33-1.38 m), flight time and distance (0.346-0.368 s; 2.74-2.79 m), entry angle (38⁰). The starting position also affects the glide phase, namely the glide time and distance (0.532-0.536 s; 2.22-2.26 m) and maximum depth (-0.91-0.92 m). Conclusions: The results of the study show that swimmers produced shorter times to 5 meters and higher velocity at 5 meters compared with other starting positions and OSB12 kick plate positions.
12
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Inter-Examiner, Within-Session and Between-Session Repeatability of Kinematic Gait Parameters Among Adult Subjects

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Leszczewska J., Czaprowski D., Pawłowska P., Oponowicz A.
Human Movement
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2012
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vol. 13
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issue 4
337-343
EN
Purpose. This research aimed to assess the repeatability of results obtained when analysing gait by means of a system designed for objective gait analysis in a single laboratory setting by a single examiner within-session and between-sessions. Methods. For the purpose of this research, the BTS Smart-D movement analysis system, produced by Capture Motion System of Italy, was used. Four healthy adults were examined. The subjects took part in three gait analysis testing sessions, with each session separated by a two-day break. During each session, two sets of measurements were taken for each subject. Statistical analysis was performed with StatSoft’s Statistica 7.1 software. Results. Within each session, all examined temporal and spatial parameters were found to be repeatable. Only in hip and knee joint rotation was repeatability not confirmed within session. Between the sessions, repeatability was confirmed in pelvic rotation, abduction/adduction of the knee joint and for all foot kinematic parameters. Conclusions. Conducting gait analysis by one researcher does not guarantee obtaining repeatable results for all measured kinematic parameters, either within one session or between sessions; caution ought to be exercised when interpreting results. Among the studied parameters, hip and knee joint rotation provided the most difficulty in obtaining repeatable results. For this reason, diagnostic and therapeutic decisions based on such data require the utmost consideration.
13
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Biomechanical Performance Factors for Development of Minimum Disability Requirements in Para-taekwondo – Part 1

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O’Sullivan D., Fife G. P.
Central European Journal of Sport Sciences and Medicine
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2015
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vol. 11
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issue 3
63-69
EN
Objective: To assess taekwondo sparring performance variables, such as joint ranges of motion, reaction times, and kicking foot speeds, to serve as a framework for developing sport-specific classification in Para-taekwondo competition. Methods: After a standard taekwondo warm up, athletes executed five popular scoring techniques, back kick, cut kick, fast kick, turning kick, and tornado kick five times each (25 total). Kinematic and kinetic variables were recorded by a motion capture system of seven infrared cameras and two force plates. Maximum joint range of motion, foot velocities, and reaction time were calculated. Results: Collapsed over kick, maximum hip abduction motion, maximum hip flexion, maximum knee flexion, peak foot velocity, reaction time for male athletes were 47.8 ±10.4°, 46.3 ±7.6°, 105.3 ±14.0°, 11.5 ±2.4 m/s, and 0.46 ±0.06 s respectively. maximum hip abduction motion, maximum hip flexion, maximum knee flexion, peak foot velocity, reaction time for female athletes were 49.1 ±6.8°, 43.9 ±11.0°, 94.2 ±13.7°, 10.9 ±2.2 m/s, and 0.48 ±0.11 s respectively. Conclusions: The results of this study provide a foundational framework for future studies designed to compare and assess Para-taekwondo athletes with various physical and neurological impairments. From this, future studies may move towards developing practical on-site sport specific testing methods which may ultimately assist in making taekwondo-specific classification for Para-taekwondo competitions.
14
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The influence of lower extremity coronal plane movements on the passive regulation of instantaneous loading mechanics during running

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Sinclair J. K., Taylor P. J., Hobbs S. J.
|
EN
Background: The repetitive transmission of impact forces may contribute to the aetiology of overuse injuries. Therefore determining the mechanisms that regulate impact loading has potential clinical significance.This study aimed to determine the influence of lower extremity coronal plane kinematics on the regulation of impact loading during running. Material/Methods: Thirty-six participants ran at 4.0 m.s-1striking the centre of a piezoelectric force platform with their dominant limb. Coronal plane angular kinematics about the hip, knee and ankle joints were measured using an eight-camera motion analysis system operating at 250 Hz. Regression analyses with instantaneous loading rate magnitude as a criterion were used to identify the coronal plane parameters associated with impact loading. Results: The overall regression model yielded Adj R2 = 0.37, p ≤ 0.01. Two biomechanical parameters were obtained as significant predictors of the instantaneous loading rate. Peak ankle eversion Adj R2 = 0.22, p ≤ 0.01 and peak eversion angular velocity of the ankle Adj R2 = 0.15, p ≤ 0.01 were found to be significant predictors of instantaneous loading rate. Conclusions: The findings of the current investigation therefore suggest that passive joint motions in the coronal plane can regulate the magnitude of impact loading, linked to the development of chronic injuries.
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The Test-Retest Reliability of Anatomical Co-Ordinate Axes Definition for the Quantification of Lower Extremity Kinematics During Running

88%
Sinclair J., Taylor P. J., Greenhalgh A., Edmundson C. J., Brooks D., Hobbs S. J.
Journal of Human Kinetics
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2012
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vol. 35
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issue 1
15-25
EN
Three-dimensional (3-D) kinematic analyses are used widely in both sport and clinical examinations. However, this procedure depends on reliable palpation of anatomical landmarks and mal-positioning of markers between sessions may result in improperly defined segment co-ordinate system axes which will produce in-consistent joint rotations. This had led some to question the efficacy of this technique. The aim of the current investigation was to assess the reliability of the anatomical frame definition when quantifying 3-D kinematics of the lower extremities during running. Ten participants completed five successful running trials at 4.0 m·s-1 ± 5%. 3-D angular joint kinematics parameters from the hip, knee and ankle were collected using an eight camera motion analysis system. Two static calibration trials were captured. The first (test) was conducted prior to the running trials following which anatomical landmarks were removed. The second was obtained following completion of the running trials where anatomical landmarks were re-positioned (retest). Paired samples t-tests were used to compare 3-D kinematic parameters quantified using the two static trials, and intraclass correlations were employed to examine the similarities between the sagittal, coronal and transverse plane waveforms. The results indicate that no significant (p>0.05) differences were found between test and retest 3-D kinematic parameters and strong (R2≥0.87) correlations were observed between test and retest waveforms. Based on the results obtained from this investigation, it appears that the anatomical co-ordinate axes of the lower extremities can be defined reliably thus confirming the efficacy of studies using this technique.
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The Effects of Resisted Sprint Training on Speed Performance in Women

88%
Makaruk B., Sozański H., Makaruk H., Sacewicz T.
Human Movement
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2013
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vol. 14
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issue 2
116-122
EN
Purpose. The main aim of the study was to examine the effects of resisted and standard sprint training on the kinematics of sprintrunning acceleration in women. Methods. Thirty-six untrained but physically active female college students were randomly assigned to one of three groups: a running resisted training group (RTG, n = 12), a standard training group (STG, n = 12), and a control group (CON, n = 12). All participants in the experimental groups trained three times a week for four weeks, followed by a 1-week training break, after which they trained again for four weeks. Pre-training, post-training and detraining (three weeks after completing the training programs) measures of mean running velocity, stride length, stride frequency, knee angle at toe off and footstrike, ground contact time, and flight time were analyzed by a 20 m sprint test. Results. The RTG improved mean running velocity and increased stride length and knee angle at toe off. Simultaneously, the RTG featured decreased stride frequency and increased ground contact time. The STG demonstrated an increase in mean running velocity due to higher stride frequency and a decrease in ground contact time. All of the measured parameters did not significantly decrease after the three-week detraining period. The control group featured no changes. Conclusions. Both resisted and standard sprint training improves speed in sprint-running acceleration in women by improving different sprint kinematic parameters.
17
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Analysis of Speed Performance In Soccer by a Playing Position and a Sports Level Using a Laser System

88%
Ferro A., Villacieros J., Floría P., Graupera J. L.
Journal of Human Kinetics
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2014
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vol. 44
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issue 1
143-153
EN
The purpose of this study was to determine the kinematic variables that identify the quality of velocity in soccer players at different competitive levels and playing positions. This study had two independent variables: 1) a competitive level (competitive and non-competitive players); and 2) a playing position, with four levels (central defenders, wide defenders/midfielders, central midfielders and forwards). Forty-two soccer players took part in a 30 m sprint-test, which was measured using a laser sensor-type 1 (LDM301-Jenoptik) at 2000 Hz. Absolute and relative times, average velocities and absolute and relative maximum velocities over 10 m sections were analyzed at 200 Hz with BioLaserSport®. There were no significant differences in average velocity between competitive and non-competitive players; however, the former reached a greater maximum velocity in the 10-20 m section. Average velocity in the 0-10 m section identified specificity among playing positions in competitive players. The forwards were the fastest followed by the central midfielders, the wide defenders/midfielders and the central defenders. No differences were found among the non-competitive players. Average velocity over the 0-10 meter section may be an important indicator when assigning a playing position for competitive players. These results support the use of more accurate systems, such as a laser system, to identify soccer players’ speed qualities (including maximum velocity) during short sprints.
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Effect of Fatigue Upon Performance and Electromyographic Activity in 6-RM Bench Press

88%
Tillaar R. v. d., Saeterbakken A.
Journal of Human Kinetics
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2014
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vol. 40
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issue 1
57-65
EN
The aim of this study was to examine the effect of fatigue during one set of 6-RM bench pressing upon the muscle patterning and performance. Fourteen resistance-trained males (age 22.5±2.0 years, stature 1.82±0.07 m, body mass 82.0±7.8 kg) conducted a 6-RM bench press protocol. Barbell kinematics and EMG activity of pectoralis major, deltoid anterior, biceps brachii, triceps brachii, rectus abdominis, oblique external and erector spinae were measured in each repetition during the 6-RM bench press. Total lifting time increased and the velocity in the ascending movement decreased (p≤0.001). However, the kinematics in the descending phase deferred: the time decreased and velocity increased during the 6-RM (p≤0.001). Generally, muscles increased their EMG amplitude during the six repetitions in the ascending movement, while only three of the seven measured muscles showed an increase over the six repetitions in the descending part in 6-RM bench pressing. It was concluded that the bench pressing performance decreased (lower barbell velocities and longer lifting times) with increasing fatigue in the 6-RM execution. Furthermore EMG increased in the prime movers and the trunk stabilizers (abdominal and spine), while the antagonist muscle (biceps) activity was not affected by fatigue during the lifting phase in a single set of 6-RM bench pressing
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Effect of Three Technical Arms Swings on The Elevation of the Center of Mass During a Standing Back Somersault

88%
Mkaouer B., Jemni M., Amara S., Chaabène H., Padulo J., Tabka Z.
Journal of Human Kinetics
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2014
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vol. 40
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issue 1
37-48
EN
Arms swing during standing back somersaults relates to three different “gymnastics schools”, each is considered “optimal” by its adepts. In the three cases, technical performance, elevation and safety differ. Therefore, the aim of this study was to compare the mechanical variables of three different arms swing techniques in the performance of a standing back tucked somersault. Five high-level male gymnasts (age: 23.17±1.61 yrs; body height: 1.65±0.05 m; body mass: 56.80±7.66 kg) randomly performed standing somersaults under three conditions, each following a different arms’ swing technical angle (270°, 180° and 90°). A force plate synchronized with a three dimensional movement analysis system was used to collect kinetic and kinematic data. Significant differences were observed between somersaults’ performance. The back somersault performed with 270° arms swing showed the best vertical displacement (up to 13.73%), while the back somersaults performed with 180° arms swing showed a decrease in power (up to 22.20%). The back somersault with 90° arms swing showed the highest force (up to 19.46%). Considering that the higher elevation of the centre of mass during the flight phase would allow best performance and lower the risk of falls, this study demonstrated that optimal arms’ swing technique prior to back tucked somersault was 270°.
20
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Exploratory Investigation of Impact Loads During the Forward Handspring Vault

88%
Penitente G., Sands W. A.
Journal of Human Kinetics
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2015
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vol. 46
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issue 1
59-68
EN
The purpose of this study was to examine kinematic and kinetic differences in low and high intensity hand support impact loads during a forward handspring vault. A high-speed video camera (500 Hz) and two portable force platforms (500 Hz) were installed on the surface of the vault table. Two-dimensional analyses were conducted on 24 forward handspring vaults performed by 12 senior level, junior Olympic program female gymnasts (16.9 ±1.4 yr; body height 1.60 ±0.1 m; body mass 56.7 ±7.8 kg). Load intensities at impact with the vault table were classified as low (peak force < 0.8 × body weight) and high (peak force > 0.8 × body weight). These vaults were compared via crucial kinetic and kinematic variables using independent t-tests and Pearson correlations. Statistically significant (p < 0.001) differences were observed in peak force (t(24) = 4.75, ES = 3.37) and time to peak force (t(24) = 2.07, ES = 1.56). Statistically significant relationships between the loading rate and time to peak force were observed for high intensity loads. Peak force, time to peak force, and a shoulder angle at impact were identified as primary variables potentially involved in the determination of large repetitive loading rates on the forward handspring vault.
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