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Study Design Controlled laboratory study. Objective To evaluate the ability of 3 methods to assess static foot posture to predict rearfoot and midfoot kinematics during gait. Background Static foot posture is commonly used clinically to infer dynamic function. Limitations of static clinical assessments may be overcome through advances in technologies, including commercially available depth cameras. Methods The Foot Posture Index (FPI) of 31 males (average age, 22.5 years) was assessed using visual observation, a 3-D motion-analysis system, and a depth camera. Pearson correlations were used to evaluate relationships between FPI items and rearfoot and midfoot kinematics during walking. The ability of the static variables to predict dynamic function was assessed using multiple linear regression. Results Most FPI items (85%) were not correlated with foot kinematics, regardless of assessment method. There were 6 fair to moderate correlations between visual FPI items and total rearfoot (r = -0.36 to -0.39, P<.05) and midfoot (r = 0.37 to 0.61, P<.05) motion, 2 fair correlations between 3-D motion-analysis FPI items and total midfoot (r = -0.43, P = .02) and peak rearfoot (r = -0.40, P = .03) motion, and 2 fair correlations between the depth-camera FPI items and average rearfoot (r = -0.38 to 0.44, P<.05) motion. Visual assessment of the FPI provided the best prediction model, explaining 37% of the variance in total midfoot inversion/eversion. Conclusion Static measures of foot posture are weakly correlated with rearfoot or midfoot kinematics, and have limited dynamic prediction ability. Our findings suggest that the FPI may not be an accurate representation of rearfoot or midfoot movement during walking, regardless of the measurement technique employed. [ABSTRACT FROM AUTHOR]

The article presents a study conducted to evaluate the kinematics for performance of faster sprint acceleration among nonstriking experienced batsmen while playing quick single match. Several factors that were calculated by using analysis of variance method includes motion analysis, effect sizes and Pearson's correlations.

The punt kick is a fundamental skill used in several team sports; however, there has been a lack of research on how fatigue affects its technique. The purpose of this study was to determine the effects of short-term fatigue on punt-kicking performance. Eight elite and sub-elite Australian Football players performed maximal drop punt kicks on their preferred leg prior to, during and after a match-specific fatigue protocol. Optotrak Certus collected kinematic data from kick foot toe-off until ball contact. Repeated-measures analysis of variance showed a significant increase in 20 m sprint times after each short-term protocol, indicating fatigue. Foot speed did not significantly change with fatigue; however, increases in the range of motion at the pelvis and kicking thigh, along with increases in kicking thigh angular velocity, occurred. For the support leg, maximum knee flexion angular velocity increased while there was greater flexion found at the knee and hip, and greater range of motion at the knee. Players are able to make kinematic adaptations in order to maintain foot speed while punting for maximal distance after short-term efforts. [ABSTRACT FROM AUTHOR]

Patellar tendinopathy is the most common knee injury incurred in volleyball, with its prevalence in elite athletes more than three times that of their sub-elite counterparts. The purpose of this study was to determine whether patellar tendinopathy risk factors differed between elite and sub-elite male volleyball players. Nine elite and nine sub-elite male volleyball players performed a lateral stop-jump block movement. Maximum vertical jump, training history, muscle extensibility and strength, three-dimensional landing kinematics (250 Hz), along with lower limb neuromuscular activation patterns (1500 Hz), and patellar tendon loading were collected during each trial. Multivariate analyses of variance ( P < 0.05) assessed for between-group differences in risk factors or patellar tendon loading. Significant interaction effects were further evaluated using post-hoc univariate analysis of variance tests. Landing kinematics, neuromuscular activation patterns, patellar tendon loading, and most of the previously identified risk factors did not differ between the elite and sub-elite players. However, elite players participated in a higher training volume and had less quadriceps extensibility than sub-elite players. Therefore, high training volume is likely the primary contributor to the injury discrepancy between elite and sub-elite volleyball players. Interventions designed to reduce landing frequency and improve quadriceps extensibility are recommended to reduce patellar tendinopathy prevalence in volleyball players. [ABSTRACT FROM AUTHOR]

The aim of this study was to simultaneously assess the changes in physiology, and kinematic and spatiotemporal features of gait, during prolonged load carriage in individuals without load carriage experience. Eleven males, representative of new military recruits, walked for 120 min at 5.5 km h− 1, 0% grade, on a motorised treadmill while carrying a 22 kg load. The load ( ≤ 30% body mass) was distributed over a weighted vest, combat webbing and replica model firearm, to reflect a patrol order load. Oxygen consumption and heart rate increased throughout the trial; however, apart from a minor increase in step length, there were no changes in the kinematic or spatiotemporal parameters, despite an increase in perceived exertion and discomfort. These data suggest that individuals with no experience in load carriage are able to maintain normal gait during 2 h of fixed speed walking, while carrying a patrol order load ≤ 30% body mass. Practitioner Summary:It is presumed that lower limb injury is associated with prolonged load carriage, especially in new military recruits. Our results suggest that prolonged carriage of a 22 kg load does not cause any functionally relevant gross biomechanical changes despite an increase in the physiological demands and perceived intensity of the task. [ABSTRACT FROM AUTHOR]

Enhancing the understanding of coordination and variability in the tennis serve may be of interest to coaches as they work with players to improve performance. The current study examined coordinated joint rotations and variability in the lower limbs, trunk, serving arm and ball location in the elite female tennis serve. Pre-pubescent, pubescent and adult players performed maximal effort flat serves while a 22-camera 500 Hz motion analysis system captured three-dimensional body kinematics. Coordinated joint rotations in the lower limbs and trunk appeared most consistent at the time players left the ground, suggesting that they coordinate the proximal elements of the kinematic chain to ensure that they leave the ground at a consistent time, in a consistent posture. Variability in the two degrees of freedom at the elbow became significantly greater closer to impact in adults, possibly illustrating the mechanical adjustments (compensation) these players employed to manage the changing impact location from serve to serve. Despite the variable ball toss, the temporal composition of the serve was highly consistent and supports previous assertions that players use the location of the ball to regulate their movement. Future work should consider these associations in other populations, while coaches may use the current findings to improve female serve performance. [ABSTRACT FROM AUTHOR]

Handballing in Australian football (AF) is the most efficient passing method, yet little research exists examining technical factors associated with accuracy. This study had three aims: (a) To explore the kinematic differences between accurate and inaccurate handballers, (b) to compare within-individual successful (hit target) and unsuccessful (missed target) handballs and (c) to assess handballing when both accuracy and speed of ball-travel were combined using a novel approach utilising canonical correlation analysis. Three-dimensional data were collected on 18 elite AF players who performed handballs towards a target. More accurate handballers exhibited a significantly straighter hand-path, slower elbow angular velocity and smaller elbow range of motion (ROM) compared to the inaccurate group. Successful handballs displayed significantly larger trunk ROM, maximum trunk rotation velocity and step-angle and smaller elbow ROM in comparison to the unsuccessful handballs. The canonical model explained 73% of variance shared between the variable sets, with a significant relationship found between hand-path, elbow ROM and maximum elbow angular velocity (predictors) and hand-speed and accuracy (dependant variables). Interestingly, not all parameters were the same across each of the analyses, with technical differences between inaccurate and accurate handballers different from those between successful and unsuccessful handballs in the within-individual analysis. [ABSTRACT FROM PUBLISHER]

This study examined the perceived effort, success rates and kinematics for three push strategies in a simulated lateral patient transfer (horizontal slide). Thirteen healthy subjects (four males) completed three repetition pushing loads of 6, 10 and 14 kg in random order; with a spontaneous push strategy, then with a straight-back bent-knees (squat) strategy and the preparatory pelvic movement (‘rockback’) strategy in random order. Perceived effort and kinematic parameters measured at the onset of movement and at maximum push excursion were compared between strategies and between loads with repeated measures ANOVA. The spontaneous and ‘rockback’ strategies achieved the pushing task with less perceived effort across all loads than the squat push (P < 0.001). Only 3/13 participants were successful on all attempts at pushing the 14 kg load using a squat strategy, which contrasted with 12/13 participants when the spontaneous strategy or the ‘rockback’ strategy was used. Forward movement of the pelvis and forward trunk inclination may be positively associated with lower perceived effort in the push task. Practitioner Summary:In a manual-handling task that simulated a lateral patient transfer (horizontal slide), perceived effort and success rates of three push strategies were compared. A straight-back bent-knees push (squat) strategy demonstrated greater perceived effort and lower success rates than a spontaneous push strategy, or a push strategy with preparatory ‘rockback’ pelvic movement. [ABSTRACT FROM AUTHOR]

In Australian football (AF), handballing proficiently with both the preferred and non-preferred arm is important at elite levels; yet, little information is available for handballing on the non-preferred arm. This study compared preferred and non-preferred arm handballing techniques. Optotrak Certus (100 Hz) collected three-dimensional data for 19 elite AF players performing handballs with the preferred and non-preferred arms. Position data, range of motion (ROM), and linear and angular velocities were collected and compared between preferred and non-preferred arms using dependentt-tests. The preferred arm exhibited significantly greater forearm and humerus ROM and angular velocity and significantly greater shoulder angular velocity at ball contact compared to the non-preferred arm. In addition, the preferred arm produced a significantly greater range of lateral bend and maximum lower-trunk speed, maximum strike-side hip speed and hand speed at ball contact than the non-preferred arm. The non-preferred arm exhibited a significantly greater shoulder angle and lower- and upper-trunk orientation angle, but significantly lower support-elbow angle, trunk ROM, and trunk rotation velocity compared to the preferred arm. Reduced ROM and angular velocities found in non-preferred arm handballs indicates a reduction in the degrees of freedom and a less developed skill. Findings have implication for development of handballing on the non-preferred arm. [ABSTRACT FROM AUTHOR]

BACKGROUND: The safe maximal lift for a person is often determined during a functional capacity evaluation. This determination is based upon observation of unsafe lifting techniques, however there is limited information on specific kinematic changes that assist a therapist's clinical reasoning and determination of the safe maximal lift. OBJECTIVE: To evaluate any change in kinematics between safe minimum and safe maximum floor-to-bench lifts during the WorkHab Functional Capacity Evaluation. METHOD: Twenty-eight healthy participants (age range 18-22 years) were digitally recorded completing the evaluation. Lumbar spine, hip, knee and ankle joint angles were measured using Dartfish Pro-suite software at the beginning (0/3), one third (1/3), two thirds (2/3) and end (3/3) of the lift in descending and ascending phases. Paired t-tests were used to compare joint angles at each point of minimum and safe maximum lifts. RESULTS: Significant changes in joint angles occurred lifting safe maximum weight compared to minimum weight. The lumbar spine was in greater flexion [4.9, 95% CI 2.1:7.7, p=0.001]; the knee joint was in less flexion descending [-4.5, 95% CI -8.1: -0.8, p=0.004 (3/3)] and ascending [-9.7, 95% CI -18.3: -1.16, p=0.027 (0/3)] and hip flexion increased at all points of the ascending phase (p&les; 0.021). The ankle joint was in less dorsiflexion while descending [8.0, 95% CI 3.4:12.7, p=0.001(2/3); 6.7, 95% CI 4.4:9.0, p&les;0.001(3/3)] and ascending [8.9, 95% CI 6.24:11.6, p=0.001(0/3); 3.6, 95% CI 1.5:5.7, p&les;0.001(3/3)]. CONCLUSIONS: This study provides insight into kinematic changes and support observations made by the WorkHab assessor in determining a safe maximal lift during floor-to-bench lifts. [ABSTRACT FROM AUTHOR]

The handball pass is influential in Australian football, and achieving higher ball speeds in flight is an advantage in increasing distance and reducing the chance of interceptions. The purpose of this study was to provide descriptive kinematic data and identify key technical aspects of maximal handball performance. Three-dimensional full body kinematic data from 19 professional Australian football players performing handball pass for maximal speed were collected, and the hand speed at ball contact was used to determine performance. Sixty-four kinematic parameters initially obtained were reduced to 15, and then grouped into like components through a two-stage supervised principal components analysis procedure. These components were then entered into a multiple regression analysis, which indicated that greater hand speed was associated with greater shoulder angular velocity and separation angle between the shoulders and pelvis at ball contact, as well as an earlier time of maximum upper-trunk rotation velocity. These data suggested that in order to increase the speed of the handball pass in Australian football, strategies like increased shoulder angular velocity, increased separation angle at ball contact, and earlier achievement of upper-trunk rotation speed might be beneficial. [ABSTRACT FROM PUBLISHER]

Office workers perform tasks using different information and communication technologies (ICT) involving various postures. Adequate variation in postures and muscle activity is generally believed to protect against musculoskeletal complaints, but insufficient information exists regarding the effect on postural variation of using different ICT. Thus, this study among office workers aimed to determine and compare postures and postural variation associated with using distinct types of ICT. Upper arm, head and trunk postures of 24 office workers were measured with the Physiometer® over a whole day in their natural work and away-from-work environments. Postural variation was quantified using two indices: APDF(90-10)and EVA(sd). Various ICT had different postural means and variation. Paper-based tasks had more non-neutral, yet also more variable postures. Electronics-based tasks had more neutral postures, with less postural variability. Tasks simultaneously using paper- and electronics-based ICT had least neutral and least variable postures. Tasks without ICT usually had the most posture variability. Interspersing tasks involving different ICT could increase overall exposure variation among office workers and may thus contribute to musculoskeletal risk reduction. Practitioner Summary:This study in office workers assessed posture variation, which is believed to protect against musculoskeletal complaints. Electronics-based tasks had more neutral upper body postures but less posture variation than other tasks. Combining tasks based on different technologies could increase postural variation in and outside the job for office workers. [ABSTRACT FROM AUTHOR]

Eccentric contractions that provide spring energy can also cause muscle damage. The aim of this study was to explore leg and vertical stiffness following muscle damage induced by an eccentric exercise protocol. Twenty active males completed 60 minutes of backward-walking on a treadmill at 0.67 m/s and a gradient of − 8.5° to induce muscle damage. Tests were performed immediately before; immediately post; and 24, 48, and 168 hours post eccentric exercise. Tests included running at 3.35 m/s and hopping at 2.2 Hz using single- and double-legged actions. Leg and vertical stiffness were measured from kinetic and kinematic data, and electromyography (EMG) of five muscles of the preferred limb were recorded during hopping. Increases in pain scores (over 37%) occurred post-exercise and 24 and 48 hours later (p < 0.001). A 7% decrease in maximal voluntary contraction occurred immediately post-exercise (p = 0.019). Changes in knee kinematics during single-legged hopping were observed 168 hours post (p < 0.05). No significant changes were observed in EMG, creatine kinase activity, leg, or vertical stiffness. Results indicate that knee mechanics may be altered to maintain consistent levels of leg and vertical stiffness when eccentric exercise-induced muscle damage is present in the lower legs. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to investigate the effect stride length has on ankle biomechanics of the leading leg with reference to the potential risk of injury in cricket fast bowlers. Ankle joint kinematic and kinetic data were collected from 51 male fast bowlers during the stance phase of the final delivery stride. The bowling cohort comprised national under-19, first class and international-level athletes. Bowlers were placed into either Short, Average or Long groups based on final stride length, allowing statistical differences to be measured. A multivariate analysis of variance with a Bonferroni post-hoc correction (α = 0.05) revealed significant differences between peak plantarflexion angles (Short-LongP = 0.005, Average and LongP = 0.04) and negative joint work (Average-LongP = 0.026). This study highlighted that during fast bowling the ankle joint of the leading leg experiences high forces under wide ranges of movement. As stride length increases, greater amounts of negative work and plantarflexion are experienced. These increases place greater loads on the ankle joint and move the foot into positions that make it more susceptible to injuries such as posterior impingement syndrome. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to determine whether using a direct kinematic (DK) or inverse kinematic (IK) modeling approach could influence the estimation of knee joint kinematics, kinetics, and ACL injury risk classification during unanticipated side cutting. Methods: The three-dimensional motion and force data of 34 amateur Australian rules footballers conducting unanticipated side-cutting maneuvers were collected. The model used during the DK modeling approach was an eight-segment lower body model with the hip, knee, and ankle free to move in six degrees of freedom. During the IK modeling approach, the same eight-segment model was used; however, translational constraints were imposed on the hip, knee, and ankle joints. The similarity between kinematic and kinetic waveforms was evaluated using the root mean square difference (RMSD) and the one-dimensional statistical parametric mapping (SPM1D). The classification of an athlete’s ACL injury risk was determined by correlating their peak knee moments with a predefined injury risk threshold. Results: The greatest RMSD occurred in the frontal plane joint angles (RMSD = 10.86°) and moments (RMSD = 0.67 ±0.18 Nm-kg-1), which were also shown to be significantly different throughout the stance phase in the SPM1D analysis. Both DK and IK modeling approaches classified the same athletes as being at risk of ACL injury. Conclusions: The choice of a DK or an IK modeling approach affected frontal plane estimates of knee joint angles and peak knee moments during the weight acceptance phase of unanticipated side cutting. However, both modeling approaches were similar in their classification of an athlete’s ACL injury risk. [ABSTRACT FROM AUTHOR]

The article presents a study on speed performance improvement in field sports through the use of sprint training (ST) and plyometrics training (PT). Topics include step kinematics, stance kinetics, and sprint time. Vertical force (VF), horizontal force (HF), and resultant force (RF) are also discussed.

The article reports on research which was conducted to investigate kinematic and kinetic improvements associated with action observation facilitated learning of the power clean technique in Australian football players. Researchers evaluated 15 players. They found that action observation combined with verbal coaching resulted in faster technique improvements and in improved playing performance.

Cricket fielding often involves maximal acceleration to retrieve the ball. There has been no analysis of acceleration specific to cricketers, or for players who field primarily in the infield (closer to the pitch) or outfield (closer to the boundary). This study analyzed the first two steps of a 10-m sprint in experienced cricketers. Eighteen males (age = 24.06 ± 4.87 years; height = 1.81 ± 0.06 m; mass = 79.67 ± 10.37 kg) were defined as primarily infielders (n = 10) or outfielders (n = 8). Timing lights recorded 0-5 and 0-10 m time. Motion capture measured first and second step kinematics, including: step length; step frequency; contact time; shoulder motion; lead and rear arm elbow angle; drive leg hip and knee extension, and ankle plantar flexion; swing leg hip and knee flexion, and ankle dorsi flexion. A one-way analysis of variance (p < 0.05) determined betweengroup differences. Data was pooled for a Pearson's correlation analysis (p < 0.05) to analyze kinematic relationships. There were no differences in sprint times, and few variables differentiated infielders and outfielders. Left shoulder range of motion related to second step length (r = 0.471). First step hip flexion correlated with both step lengths (r = 0.570-0.598), and frequencies (r = -0.504--0.606). First step knee flexion related to both step lengths (r = 0.528-0.682), and first step frequency (r = - 0.669). First step ankle plantar flexion correlated with second step length (r = -0.692) and frequency (r = 0.726). Greater joint motion ranges related to longer steps. Cricketers display similar sprint kinematics regardless of fielding position, likely because players may field in the infield or outfield depending on match situation. Due to relationships with shoulder and leg motion, and the importance and trainability of step length, cricketers should target this variable to enhance acceleration. [ABSTRACT FROM AUTHOR]

Purpose: This study compared regional lumbar (upper and lower), pelvis, trunk, and lower limb kinematics between elite male adolescent players with and without a history of low back pain (LBP) during the kick and flat serves as well as regional lumbar mobility and serving kinematics relative to the end of range. Methods: Seven players with a history of LBP and confirmed L4/L5 injury and 13 controls matched for age, height, mass, and performance underwent a three-dimensional motion analysis during serving trials and lumbar mobility assessments. Regional lumbar, pelvis, trunk, and lower limb kinematics were compared between pain/no pain and kick/flat serves using a series of 2 x 2 mixed- model ANOVA, with independent samples Wests used to compare regional lumbar mobility between pain/no pain. Results: The pain group had significantly reduced lower lumbar mobility in every plane of motion than the no pain group. The pain group demonstrated less right lower lumbar and pelvis/shoulder rotation, greater right pelvic tilt, earlier peak right knee extension velocity during the drive phase of the tennis serves, and greater lower lumbar and pelvis left rotation, upper lumbar left lateral flexion, and anterior pelvis tilt during the forward-swing phase. All players approached their lumbar end of range during the serve. Conclusions: The results of this investigation suggest that a multidimensional LBP management and prevention strategy is required, including the assessment of regional spinal mobility, the lower limb and upper limb and spinal kinematics, and the integrated work between clinicians and coaches to adapt adverse technique [ABSTRACT FROM AUTHOR]

Understanding the magnitude of forces and lower body kinematics that occur during a change of direction (COD) task can provide information about the biomechanical demands required to improve performance. To compare the magnitude of force, impulse, lower body kinematics and post-COD stride velocity produced between athletes of different strength levels during a COD task, 12 stronger (8 males, 4 females) and 12 weaker (4 males, 8 females) recreational team sport athletes were recruited. Strength levels were determined by relative peak isometric force of the dominant and non-dominant leg. All athletes performed 10 pre-planned 45° changes of direction (5 left, 5 right) while three-dimensional motion and ground reaction force (GRF) data were collected. Differences in all variables for the dominant leg were examined using a one-way analysis of variance (ANOVA) with a level of significance set atp≤0.05. The stronger group displayed significantly faster post-COD stride velocity and greater vertical and horizontal braking forces, vertical propulsive force, vertical braking impulse, horizontal propulsive impulse, angle of peak braking force application, hip abduction and knee flexion angle compared to the weaker group. The results suggest that individuals with greater relative lower body strength produced higher magnitude plant foot kinetics and modified lower body positioning while producing faster COD performances. Future investigations should determine if strength training to enable athletes to increase plant foot kinetics while maintaining or adopting a lower body position results in a concomitant increases in post-COD stride velocity. [ABSTRACT FROM AUTHOR]

Two distinctly separate training facilities (dry-land and aquatic) are routinely used in springboard diving and pose an interesting problem for learning, given the inherent differences in landing (head first vs. feet first) imposed by the different task constraints. Although divers may practise the same preparation phase, take-off and initial aerial rotation in both environments, there is no evidence to suggest that the tasks completed in the dry-land training environment are representative of those performed in the aquatic competition environment. The aim of this study was to compare the kinematics of the preparation phase of reverse dives routinely practised in each environment. Despite their high skill level, it was predicted that individual analyses of elite springboard divers would reveal differences in the joint coordination and board-work between take-offs. The two-dimensional kinematic characteristics were recorded during normal training sessions and used for intra-individual analysis. Kinematic characteristics of the preparatory take-off phase revealed differences in board-work (step lengths, jump height, board depression angles) for all participants at key events. However, the presence of scaled global topological characteristics suggested that all participants adopted similar joint coordination patterns in both environments. These findings suggest that the task constraints of wet and dry training environments are not similar, and highlight the need for coaches to consider representative learning designs in high performance diving programmes. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare kinematics and muscle activity between chin-ups and lat-pull down exercises and between muscle groups during the two exercises. Normalized electromyography (EMG) of biceps brachii (BB), triceps brachii (TB), pectoralis major (PM), latissimus dorsi (LD), rectus abdominus (RA), and erector spinae (ES) and kinematics of back, shoulder, and seventh cervical vertebrae (C7) was analysed during chin-ups and lat-pull down exercises. Normalized EMG of BB and ES and kinematics of shoulder and C7 for chin-ups were greater than lat-pull down exercises during the concentric phase (p < 0.05). For the eccentric phase, RA during lat-pull down exercises was greater than chin-ups and the kinematics of C7 during chin-ups was greater than lat-pull down exercises (p < 0.05). For chin-ups, BB, LD, and ES were greater than PM during the concentric phase, whereas BB and LD were greater than TB, and LD was greater than RA during the eccentric phase (p < 0.05). For lat-pull down exercise, BB and LD were greater than PM, TB, and ES during the concentric phase, whereas LD was greater than PM, TB, and BB during the eccentric phase (p < 0.05). Subsequently, chin-ups appears to be a more functional exercise. [ABSTRACT FROM PUBLISHER]

Purpose: This study aimed to quantify and compare lumbar region kinetics in kick and flat serves performed by elite, adolescent male players with and without a history of low back pain (LBP). Lumbar region kinematics, as well as racquet velocity and the position of the ball at impact, was described to facilitate kinetic data interpretation. Methods: Twenty Tennis Australia adolescent male players participated; 7 had a history of disabling LBP and confirmed L4/L5 injury and 13 were age-, height-, mass-, and performance-matched controls. The VICON motion analysis system was used to record racquet, upper and lower limb, trunk, and lumbar movement during three "flat" and three "kick" serves. A customized mathematical model calculated lumbar region kinetics/kinematics, racquet velocity, and ball position at impact, and these are reported as if all players were right-handed. A series of 2 x 2 mixed-model ANOVA were used to compare between pain/no pain and kick/flat serves. Results: There was no significant difference in racquet velocity or ball position at impact between pain groups or serve types. The players with LBP reported significantly greater (mean difference = 1.5 N-kg~') peak left lateral force than the control group. The flat serve was associated with significantly greater flexion moments (mean difference = 2.7 Nkg~ ') than the kick serve. Conclusions: The lumbar region undergoes substantial loading during both the kick and the flat tennis serves, including lateral flexion forces approximately eight times those experienced during running. Given that these left lateral flexion forces are significantly greater in players with a history of disabling LBP and occur simultaneous with peak vertical force and extension and right lateral rotations, this may be an important LBP mechanism in this population. [ABSTRACT FROM AUTHOR]

The Demon Fault is a north-striking, dextral strike-slip fault that displaces Carboniferous to Middle Triassic rock units in eastern Australia. We present results from aeromagnetic gridded data, satellite images, digital elevation models, and field observations, which provide constraints on the geometry and kinematics of the Demon Fault. The fault can be subdivided into four steeply dipping segments (DF1 to DF4) with oblique reverse-dextral kinematics. Earlier NW-striking faults, which affected Early and Middle Triassic magmatic rocks, are displaced by the Demon Fault, implying that activity along the Demon Fault has occurred during the latest Middle Triassic or later. The amount of dextral offset along the different parts of the Demon Fault is decreased towards the south. This suggests that either different segments have experienced different histories of reactivation, or that deformation toward the south has partitioned into minor splays, which operated as reverse faults and resulted in a lesser dextral displacement. We propose that the Demon Fault and other sub-parallel faults operated in conjunction with the development of basins in eastern Australia from Late Triassic to Early Cretaceous. The pattern of minor faults and their kinematics indicate that recent activity along the Demon Fault has occurred during dextral transpression, which we attribute to mid-Cretaceous contractional deformation, or possibly even Cenozoic deformation associated with collisional processes at the northern boundary of the Australian plate. [ABSTRACT FROM AUTHOR]

The development of a powerful and accurate serve is a priority for most tennis players. Various drills are proposed to enhance characteristics of the serve such as ball speed and spin, yet research has failed to address their efficacy. The aim of this study was therefore to compare the kinematics of a flat serve with that of a service drill, where the player serves from the knees in an endeavour to promote specific changes in trunk, arm, racket, and ball motion. A 22-camera 250 Hz VICON MX motion analysis system captured the trunk, arm, racket, and ball kinematics of eight high-performance junior players hitting flat serves and knee serves. Pairedt-tests assessed within-group kinematic differences between the two serve conditions. Changes in ball toss, trunk, arm, and racket kinematics were a manifestation of the constraints presented by the knee serve. These changes effected an increased angle of attack of the racket but without greater frontal plane trunk rotation, which represented primary objectives of the knee serve. In sum, partial support was offered to the use of the knee serve as an intervention that promotes immediate, specific changes in trunk and racket kinematics in the service actions of elite junior players. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to describe three-dimensional ball kinematics including spin axis and spin rate for the flat, slice, and kick serves executed by elite male tennis players. Trajectories of three retro-reflective markers attached to the surface of the ball were measured using a Vicon MX motion analysis system. The local coordinate system of the ball enabled the ball's angular velocity vector to be determined. Mean ( ± SD) spin rates recorded were 127.4 ( ± 56.3), 232.1 ( ± 34.8), and 336.5 ( ± 51.5) rad/s for the flat, slice, and kick serves, respectively. The resultant horizontal velocities of the ball were 52.0 ( ± 2.9), 46.4 ( ± 3.4), and 40.8 ( ± 2.8) m/s, respectively, and a clear tradeoff existed between the development of ball spin rate and horizontal ball velocity, with resultant horizontal velocities of 52.0 ( ± 2.9), 46.4 ( ± 3.4), and 40.8 ( ± 2.8) m/s, respectively, being recorded. The spin axis and ball velocity vector were close to perpendicular regardless of serve type. Mean angles between the spin axis and the horizontal plane (elevation angles) were 65.6° ( ± 10.2°), 68.4° ( ± 6.9°), and 54.5° ( ± 8.4°) for the flat, slice, and kick serves, respectively. [ABSTRACT FROM PUBLISHER]

Consistency and invariance in movements are traditionally viewed as essential features of skill acquisition and elite sports performance. This emphasis on the stabilization of action has resulted in important processes of adaptation in movement coordination during performance being overlooked in investigations of elite sport performance. Here we investigate whether differences exist between the movement kinematics displayed by five, elite springboard divers (age 17 ± 2.4 years) in the preparation phases of baulked and completed take-offs. The two-dimensional kinematic characteristics of the reverse somersault take-off phases (approach and hurdle) were recorded during normal training sessions and used for intra-individual analysis. All participants displayed observable differences in movement patterns at key events during the approach phase; however, the presence of similar global topological characteristics suggested that, overall, participants did not perform distinctly different movement patterns during completed and baulked dives. These findings provide a powerful rationale for coaches to consider assessing functional variability or adaptability of motor behaviour as a key criterion of successful performance in sports such as diving. [ABSTRACT FROM AUTHOR]

The article reports on research which was conducted to investigate the potential association with anthropometry and upper-body pulling strength with sprint kinematics of competitive surfers. Researchers evaluated 10 competitive male surfers. They found that there was a strong association between relative upper-body pulling strength and sprint paddling ability in surfers and concluded that coaches working with competitive surfers should implement strength training with the surfers.

This paper examines the upper-limb movement kinematics of young children (3-7 years) with high-functioning autism using a point-to-point movement paradigm. Consistent with prior findings in older children, a difference in movement preparation was found in the autism group (n = 11) relative to typically developing children. In contrast to typically developing children, the presence of a visual distractor in the movement task did not appear to impact on early movement planning or execution in children with autism, suggesting that this group were not considering all available environmental cues to modulate movement. The findings from this study are consistent with the possibility that autism is associated with a difficulty using visual information to prime alternative movements in a responsive way to environmental demands. [ABSTRACT FROM AUTHOR]

The article reports on research which was conducted to examine the anthropometric, vertical jump, and strength quality changes over two years in a group of national team volleyball players. Researchers evaluated 14 players. After evaluating the players for two years researchers concluded that elite male volleyball players can improve leanness and power, which contribute to improvements in vertical jump.

Anterior cruciate ligament (ACL) injury rates have increased by ∼50% over the last 10 years. These figures suggest that ACL focused research has not been effective in reducing injury rates among community level athletes. Training protocols designed to reduce ACL injury rates have been both effective (n = 3) and ineffective (n = 7). Although a rationale for the use of exercise to reduce ACL injuries is established, the mechanisms by which they act are relatively unknown. This article provides an injury prevention framework specific to noncontact ACL injuries and the design of prophylactic training protocols. It is also apparent that feedback within this framework is needed to determine how biomechanically relevant risk factors like peak joint loading and muscular support are influenced following training. It is by identifying these links that more effective ACL injury prevention training programs can be developed, and, in turn, lead to reduced ACL injury rates in the future. [ABSTRACT FROM PUBLISHER]

The article reports on research conducted to investigate the effect different speed training protocols had on sprint acceleration in field sport athletes. Researchers evaluated free sprint training, weight training, plyometric training and resisted sprint training in 35 athletes. They found when they were correctly administered, each training protocol was effective in improving acceleration and that to improve acceleration field sport athletes should develop horizontal and reactive power.

Abstract: This study investigated the potential of micro-sensors for use in the identification of the main movement patterns used in cross-country skiing. Data were collected from four elite international and four Australian athletes in Europe and in Australia using a MinimaxXTM unit containing accelerometer, gyroscope and GPS sensors. Athletes performed four skating techniques and three classical techniques on snow at moderate velocity. Data from a single micro-sensor unit positioned in the centre of the upper back was sufficient to visually identify cyclical movement patterns for each technique. The general patterns for each technique were identified clearly across all athletes while at the same time distinctive characteristics for individual athletes were observed. Differences in speed, snow condition and gradient of terrain were not controlled in this study and these factors could have an effect on the data patterns. Development of algorithms to process the micro-sensor data into kinematic measurements would provide coaches and scientists with a valuable performance analysis tool. Further research is needed to develop such algorithms and to determine whether the patterns are consistent across a range of different speeds, snow conditions and terrain, and for skiers of differing ability. [ABSTRACT FROM AUTHOR]

This study investigated the developmental variability of lip and tongue movement in 48 children and adults. Motion of the tongue-tip, tongue-body and lower lip was recorded using electromagnetic articulography during productions of sentences containing /t/, /s/, /l/, /k/ and /p/. Four groups of speakers participated in the study: (1) aged 6-7 years; (2) 8-11 years; (3) 12-17 years; and (4) adults. The variation in distance, duration, speed, acceleration and deceleration of the articulators during single open-close speech movements was analysed, and the stability of multiple movement sequences was examined using the spatiotemporal index. The experimental findings revealed a gradual developmental progression from 6 years to adulthood. At adolescence, speakers continued to exhibit significantly more variable speech motor output compared to adult speakers. The observed developmental pattern suggests that attenuated, but important, changes in the speech motor system occurs from mid-childhood, through adolescence, to adulthood. [ABSTRACT FROM AUTHOR]

The author discusses the need for monitoring of kinematic and dynamic adaptations in resisted movement training on sprinting and jumping performance. He states that added resistance which is not excessive can be provided by athletic conditioning. The author notes that training adaptations can be optimized by greater stimulus to muscle strength.

Kicking with the non-preferred leg is important in Australian Football and becoming important in the rugby codes. The aim of this study was to examine differences between preferred and non-preferred leg kicking in the drop punt kick. Seventeen elite Australian Football players performed kicks with the preferred and non-preferred leg. Optotrak Certus collected kinematic data of the kick leg and pelvis (200 Hz) from kick leg toe-off until ball contact. Foot speed, knee and shank angular velocity at ball contact, and pelvis range of motion were significantly larger for the preferred leg (P < 0.05). In contrast, hip and thigh angular velocity at ball contact and hip range of motion were significantly larger for the non-preferred leg. This indicates different movement patterns, with preferred-leg kicks making greater use of the pelvis, knee, and shank while non-preferred leg kicks rely relatively more on the hip and thigh (P < 0.05). Reasons for this difference might be due to locking degrees of freedom or sub-optimal sequencing in the non-preferred leg. The thigh–knee continuum identified by Ball (2008) was also evident in this study. Findings have implications for training non-preferred leg kicking for performance and injury prevention. [ABSTRACT FROM PUBLISHER]

Differences in interceptive skill between highly skilled and lesser skilled cricket batsmen were examined using a batting task that required participants to strike front-foot drive strokes from a machine-projected ball to a specified target. Task difficulty was manipulated by varying the width of the bat (normal, half, and third width) and target accuracy, and quality of bat–ball contact was monitored along with temporal and sequential elements of the hitting action. Analyses revealed that the highly skilled batsmen were distinguishable from less skilled counterparts by their higher accuracy under the normal and half-width bat conditions, significantly earlier initiation and completion of the front-foot stride, greater synchronization of the completion of the front-foot stride with the commencement of the downswing of the bat, and consistent timing of downswing relative to ball bounce and impact. In keeping with studies of other hitting sports, temporal and spatial coupling of the downswing to ball bounce to help minimize temporo-spatial error at the point of interception appeared critical to skilled performance. Implications for the understanding of interception and for coaching practice are briefly discussed. [ABSTRACT FROM PUBLISHER]

The serve, as the most important stroke in tennis, has attracted considerable biomechanical interest. Of its component parts, the swing has received disproportionate research attention and consequently, little is known regarding toss kinematics. Indeed, the age-old question of whether players serve to different parts of the court from the same toss remains unanswered. Six right-handed professionally ranked players hit first serves (FSs) and second serves (SSs) to three 2 × 1 m target areas reflecting the landing locations of T, body and wide serves, respectively, on the deuce court. A 22 camera, 250 Hz VICON MX motion analysis system captured racket, ball, foot, and hand kinematics. Repeated measures ANOVAs assessed within-player differences in foot, racket, and ball kinematics within the FS and SS as a function of landing location. The positions of the front foot, ball zenith, and ball impact were significantly different in the FS, while kinematics across all SS were consistent. Front foot position was closer to the centre mark in the T FS and players impacted the ball further left in the wide FS compared to the T FS. This study discusses the findings in the context of the development of the serve as well as potential implications for the return. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to investigate the relationship between the cable force and linear hammer speed in the hammer throw and to identify how the magnitude and direction of the cable force affects the fluctuations in linear hammer speed. Five male (height: 1.88 ± 0.06 m; body mass: 106.23 ± 4.83 kg) and five female (height: 1.69 ± 0.05 m; body mass: 101.60 ± 20.92 kg) throwers participated and were required to perform 10 throws each. The hammer's linear velocity and the cable force and its tangential component were calculated via hammer head positional data. As expected, a strong correlation was observed between decreases in the linear hammer speed and decreases in the cable force (normalised for hammer weight). A strong correlation was also found to exist between the angle by which the cable force lags the radius of rotation at its maximum (when tangential force is at its most negative) and the size of the decreases in hammer speed. These findings indicate that the most effective way to minimise the effect of the negative tangential force is to reduce the size of the lag angle. [ABSTRACT FROM AUTHOR]

The article presents a study on the impact of running speed on the kinetics of lower limb joints. It discusses the importance of evaluating the biomechanical function of lower limb muscles at different running speeds in improving performance and preventing injury in athletes and describes the methodology of the study in which kinematic reaction was analyzed on eight subjects during steady-state running. It concludes that maximum increase in biomechanical load was found on the lower limb muscle groups when running speed increased.

Extensive exposures of deep crustal rocks in the south-central Arunta Region record a complex tectonic history from Proterozoic terrane assembly to Paleozoic exhumation. Western Mt Chapple was previously inferred to include evidence of much of this history. Detailed mapping and structural and metamorphic analysis, however, demonstrate three structurally distinct, high-grade deformational events, but no indication of the youngest, lowermost amphibolite to greenschist facies, Alice Springs exhumational overprint. Evidence of the oldest deformation is confined to local exposures of NE-striking gneissosity; neither metamorphic grade nor kinematics are constrained. The second event produced a steeply dipping, WNW-striking, NNE-dipping foliation, steeply E-plunging mineral lineation, and kinematic indicators recording dextral transpression in present-day geographic coordinates. Mineral assemblages preserved in blocks between D3 shear zones record D2 metamorphic conditions of 691-746 ± 50°C and 550-900 MPa. Northwest-striking D3 shear zones are characterised by an exceptionally well developed, NW-striking, steeply NE-dipping foliation and steeply SE-plunging mineral lineation with kinematic indicators that demonstrate sinistral-reverse, triclinic shear. Shear zone mineral assemblages record metamorphism at 702 ± 50°C. These data demonstrate a history of high-temperature deformation, including significant strike-parallel movement, which predates the Alice Springs orogeny. [ABSTRACT FROM AUTHOR]

Running is the most important discipline for Olympic triathlon success. However, cycling impairs running muscle recruitment and performance in some highly trained triathletes; though it is not known if this occurs in elite international triathletes. The purpose of this study was to investigate the effect of cycling in two different protocols on running economy and neuromuscular control in elite international triathletes. Muscle recruitment and sagittal plane joint angles of the left lower extremity and running economy were compared between control (no preceding cycle) and transition (preceded by cycling) runs for two different cycle protocols (20-minute low-intensity and 50-minute high-intensity cycles) in seven elite international triathletes. Muscle recruitment and joint angles were not different between control and transition runs for either cycle protocols. Running economy was also not different between control and transition runs for the low-intensity (62.4 ± 4.5 vs. 62.1 ± 4.0 ml/min/kg, p>0.05) and high-intensity (63.4 ± 3.5 vs. 63.3 ± 4.3 ml/min/kg, p>0.05) cycle protocols. The results of this study demonstrate that both low- and high-intensity cycles do not adversely influence neuromuscular control and running economy in elite international triathletes. [ABSTRACT FROM AUTHOR]

Abstract: During the Early Cretaceous Australia''s eastward passage over sinking subducted slabs induced widespread dynamic subsidence and formation of a large epeiric sea in the eastern interior. Despite evidence for convergence between Australia and the paleo-Pacific, the subduction zone location has been poorly constrained. Using coupled plate tectonic–mantle convection models, we test two end-member scenarios, one with subduction directly east of Australia''s reconstructed continental margin, and a second with subduction translated ~1000km east, implying the existence of a back-arc basin. Our models incorporate a rheological model for the mantle and lithosphere, plate motions since 140Ma and evolving plate boundaries. While mantle rheology affects the magnitude of surface vertical motions, timing of uplift and subsidence depends on plate boundary geometries and kinematics. Computations with a proximal subduction zone result in accelerated basin subsidence occurring 20Myr too early compared with tectonic subsidence calculated from well data. This timing offset is reconciled when subduction is shifted eastward. Comparisons between seismic tomography and model temperature cross-sections, and an absence of subduction zone volcanism in eastern Australia in the Early Cretaceous provide support for the back-arc basin scenario. [Copyright &y& Elsevier]

Previous studies have shown that cycling can directly influence neuromuscular control during subsequent running in some highly trained triathletes, despite these triathletes' years of practice of the cycle-run transition. The aim of this study was to determine whether cycling has the same direct influence on neuromuscular control during running in moderately trained triathletes. Fifteen moderately trained triathletes participated. Kinematics of the pelvis and lower limbs and recruitment of 11 leg and thigh muscles were compared between a control run (no prior exercise) and a 30 min run that was preceded by a 15 min cycle (transition run). Muscle recruitment was different between control and transition runs in only one of 15 triathletes (<7%). Changes in joint position (mean difference of 3°) were evident in five triathletes, which persisted beyond 5 min of running in one triathlete. Our findings suggest that some moderately trained triathletes have difficulty reproducing their pre-cycling movement patterns for running initially after cycling, but cycling appears to have little influence on running muscle recruitment in moderately trained triathletes. [ABSTRACT FROM AUTHOR]

Whole body kinematics of the tennis serve have been reported extensively in the literature, yet comparatively less information exists regarding the kinematic characteristics of the swing and toss. In attempting to develop consistency in placement of the toss and racket trajectory, coaches will often decompose the serve and practice it in separate parts. A 22-camera VICON MX motion analysis system, operating at 250 Hz, captured racket, ball and hand kinematics of the serves of five elite junior players under three conditions. The conditions were flat first serves (FS) directed to a 1 × 1 m target bordering the 'T' of the deuce service box, a ball toss (BT) in isolation and a free swing (SW) in isolation. Players were instructed to perform BT and SW as in the FS. Paired t-tests assessed within-group differences in hand, racket and ball kinematics between the discrete skill and the two decomposed conditions. Vertical displacement of the ball at its zenith increased significantly during BT compared with the FS and temporal associations between racket and ball motion during the FS (r = 0.861) were affected during task decomposition. This study questions the pervasive use of task decomposition in the development of the tennis serve. [ABSTRACT FROM AUTHOR]

Serpentinites along the boundaries of the Hastings Block, southern New England Orogen, eastern Australia, contain S, C and C' structures that provide information on the kinematic history of faults bounding the block. The serpentinite bodies at Yarras on the western boundary of the Hastings Block within the Ralfes Creek, Taylors Creek and Old Highway-Yarras Mountain Trail Faults display dominantly sinistral strike-slip or oblique-slip movement. Serpentinite bodies between these faults record dextral strike-slip and oblique-slip movement histories as well as sinistral strike-slip or oblique-slip and rare normal, dip-slip movement. The Mt George Serpentinite consists of a northeast-oriented section folded and displaced by movement on a west-northwest section of the Peel-Manning Fault System. Serpentinite structures suggest the west-northwest section initially underwent dextral strike-slip, which reoriented the northeast-oriented section, and subsequently sinistral strike-slip movement. Preliminary studies of serpentinites elsewhere around the periphery of the Hastings Block indicate localised effects due to readjustment of the block during its interaction with the Nambucca Block on its northern margin. The structures observed in the serpentinites are thought to have occurred during and after the Hunter-Bowen Orogeny and prior to stitching of the accretionary-subduction and forearc by the 228 Ma Werrikimbe Caldera. [ABSTRACT FROM AUTHOR]

Abstract: Foliation Intersection/Inflection Axes within porphyroblasts (FIAs) allow the chronological and kinematic linking of deformation episodes with associated metamorphism. Measurement of FIAs in the Mesoproterozoic Eastern Fold Belt (EFB) of the Mount Isa Inlier, NE Australia, has revealed phases of deformation and metamorphism that could not previously be distinguished from one another. Both the ‘asymmetry switch’ and ‘FitPitch’ FIA measurement techniques have been applied to key localities of polymetamorphosed and multiply deformed EFB, and they yielded the same result. These independent techniques have revealed (1) E–W trending structures that formed during N–S bulk shortening (D1) and associated metamorphism (M1) formed during a period of orogenesis (O1) and N–S oriented structures that formed during E–W bulk shortening (D2) and associated metamorphism (M2) during a period of orogenesis (O2), and (2) the crustal scale tectonic processes associated with polymetamorphism. Middle to upper amphibolite facies metamorphic conditions occurred during O1 with crustal thickening followed by near-isothermal decompression leading to low-pressure/high-temperature (LP/HT) conditions with the emplacement of Williams and Naraku Batholiths around 1550 Ma. This was followed by a second period of middle-to upper-amphibolite facies metamorphism, O2. This history not only correlates better across the EFB, but also with the tectono-metamorphic model recently proposed for the Mesoproterozoic Georgetown Inlier of the north Australian Craton. [Copyright &y& Elsevier]

Kicking for distance in Australian Rules football is an important skill. Here, I examine technical aspects that contribute to achieving maximal kick distance. Twenty-eight elite players kicked for distance while being videoed at 500 Hz. Two-dimensional digitized data of nine body landmarks and the football were used to calculate kinematic parameters from kicking foot toe-off to the instant before ball contact. Longer kick distances were associated with greater foot speeds and shank angular velocities at ball contact, larger last step lengths, and greater distances from the ground when ball contact occurred. Foot speed, shank angular velocity, and ball position relative to the support foot at ball contact were included in the best regression predicting distance. A continuum of technique was evident among the kickers. At one end, kickers displayed relatively larger knee angular velocities and smaller thigh angular velocities at ball contact. At the other end, kickers produced relatively larger thigh angular velocities and smaller knee angular velocities at ball contact. To increase kicking distance, increasing foot speed and shank angular velocity at ball contact, increasing the last step length, and optimizing ball position relative to the ground and support foot are recommended. [ABSTRACT FROM AUTHOR]

Summary: A majority of sports science research is undertaken in universities and dedicated research centres, such as institutes of sport. Reviews of literature analysing and categorising research have been carried out, but categories identified have been limited to research design and data gathering techniques. Hence there is a need to include categories such as discipline, subjects and targeted sport. A study was conducted using document analysis method to gather data that described and categorised performance-based sports science research projects in Australian universities and institutes of sport. An instrument was designed that could be used by researchers to analyse and profile research in the area of sports science. The instrument contained six categories: targeted sport, primary study area, participant type, research setting, methodology and data gathering techniques. Research documents analysed consisted of 725 original unpublished research reports/theses. Results showed that over two-thirds of research projects were targeted to specific sports and, of this group, nearly half involved four sports: cycling, rowing, athletics and swimming. Overall, physiology was the most researched scientific discipline. The most frequently used research method was experimental design, and the most frequently used data gathering technique was physiological (performance) measures. Two-thirds of research was conducted in laboratory settings, and nearly half of the research was conducted with elite or sub-elite athletes as participants/subjects. The findings of this study provide an overall synopsis of performance-based sports science research conducted in Australia over the last 20 years, and should be of considerable importance in the ongoing development of sports science research policy in Australia. [Copyright &y& Elsevier]

Summary: Descriptive data on game movement demands of contemporary players in the Australian National Soccer League (NSL, now the A League) are lacking. The purpose of this study was to profile movement demands of NSL games and specifically analyse distance covered, time in various speed categories (e.g., walking, jogging, striding, etc.), number of sprint speed efforts and overall mean player speed. Video tapes of 45 players from the 2002 to 2003 NSL season were analysed for whole- and half-game movement patterns and game statistics using Trak Performance software. Bivariate and ANOVA statistics were used for between game halves and positional comparisons. Results showed no changes to the frequency and speed of high intensity demands in both halves of the game. However, a 14% slower overall speed in the second half of the game when compared with the first half was attributed to fewer observations of the low intensity movements (9.0% less walking and 12.4% less jogging) and more stationary periods. Engagement in game events such as kicking and passing was also 11.2% less frequent in the second versus first half of games. Position-specific results of higher movement speeds of midfield players (7.2kmh−1), compared with defenders (6.1kmh−1), agree with previous results from international professional leagues. The results provide position-specific directions for future conditioning drills and benchmark fitness requirements in high level soccer players. The results also highlight the challenge to ensure consistency of second-half performances for elite level soccer players in Australia. [Copyright &y& Elsevier]