An Interdisciplinary Examination of Stress and Injury Occurrence in Athletes.

This paper adopts a novel, interdisciplinary approach to explore the relationship between stress-related psychosocial factors, physiological markers and occurrence of injury in athletes using a repeated measures prospective design. At four data collection time-points, across 1-year of a total 2-year data collection period, athletes completed measures of major life events, the reinforcement sensitivity theory personality questionnaire, muscle stiffness, heart rate variability and postural stability, and reported any injuries they had sustained since the last data collection. Two Bayesian networks were used to examine the relationships between variables and model the changes between data collection points in the study.

Stance limb kinetics of older male athletes endurance running performance.

The aim of this study was to examine the age-based, lower limb kinetics of running performances of endurance athletes. Six running trials were performed by 24 male athletes, who were distinguished by three age groupings (S35: 26-32 years, M50: 50-54 years, M60+: 60-68 years). Lower limb coordinate and ground reaction force data were collected using a nine camera infra-red system synchronised with a force plate.

Kinematic adaptations in sprint acceleration performances without and with the constraint of holding a field hockey stick.

The aim of this study was to investigate the technique adaptations made when performing sprint-based tasks without (free condition) and with (constrained condition) the constraints of carrying a field hockey stick. Three free and three constrained maximal sprint accelerations were performed by 18 experienced university male field hockey players (age = 20 +/- 1 years, body mass = 73.3 +/- 7.

Considerations of force plate transitions on centre of pressure calculation for maximal velocity sprint running.

The aims of this study were to evaluate the accuracy of centre of pressure (COP) data obtained during transition of load across the boundary between two force plates, and secondly to examine the effect of such COP data on joint kinetics during sprint running performances. COP data were collected from two piezoelectric force plates as a trolley wheel was rolled across the boundary between the plates. Position data for the trolley were collected using an opto-electronic motion analysis system for comparison with COP data.

Kinematic landing strategy transference in backward rotating gymnastic dismounts.

The aim of this study was to develop insight into the transference of kinematic landing strategies between back- ward rotating dismount skills. Female gymnasts performed backward rotating pike (N = 4 x 10 trials) and tuck dismounts skills (N = 4 x 10 trials) from the beam apparatus. Whole and lower body joint kinematic measures were quantified for the impact phase using an automatic motion analysis system (CODAMotion, Charnwood Dynamics Ltd.

Implications of intra-limb variability on asymmetry analyses.

The aim of this study was to investigate the effect of intra-limb variability on the calculation of asymmetry with the purpose of informing future analyses. Asymmetry has previously been quantified for discrete kinematic and kinetic variables; however, intra-limb variability has not been routinely included in these analyses. Synchronized lower-limb kinematic and kinetic data were collected from eight trained athletes (age 22 ± 5 years, mass 74.

Influence of longswing technique on the kinematics and key release parameters of the straddle Tkachev on uneven bars.

Tkachev on uneven bars is a release and re-grasp skill performed using variations of preparatory longswing techniques; the reasons why different techniques are chosen remains unclear. This study examined kinematic and key release parameters specific to three distinct techniques with the aim of understanding the relative benefits of each. During two international artistic gymnastics competitions six arch, straddle and pike longswings preceding the straddle Tkachev were recorded using twin video cameras.

Whole-body and multi-joint kinematic control strategy variability during backward rotating dismounts from beam.

The aim of this study was to develop insight into the whole-body and multi-joint kinematic control strategy variability associated with the execution of fundamental backward rotating dismounts from beam. Two-dimensional joint centre coordinate data were obtained for ten backward piked and backward tucked somersault dismount skills performed by four female gymnasts (N = 80 trials). Gymnast-specific and group variability in whole-body and multi-joint discrete kinematic measures were compared for the aerial and impact phase of backward piked and backward tucked skills.

Intralimb joint coordination patterns of the lower extremity in maximal velocity phase sprint running.

This study aimed to develop insight into the lower extremity joint coupling motions used in the maximal velocity phase of sprint running. Two-dimensional coordinate data were used to derive sagittal plane joint angle profiles of sprint running trials. Intralimb joint coupling motions were examined using a continuous relative phase (CRP) analysis.

An image-based approach to obtaining anthropometric measurements for inertia modeling.

This study aimed to develop and evaluate an image-based method of obtaining anthropometric measurements for accurate subject-specific inertia parameter determination using Yeadon's (1990) inertia model. Ninety-five anthropometric measurements were obtained directly from five athletic performers and indirectly from digitization of subject-specific whole-body still images. The direct and image-based measurements were used as input into Yeadon's (1990) inertia model.

Interactive effects of mass proportions and coupling properties on external loading in simulated forefoot impact landings.

This study aimed to gain insight into the individual and interactive effects of segmental mass proportions and coupling properties on external loading in simulated forefoot landings. An evaluated four-segment wobbling mass model replicated forefoot drop landings (height: 0.46 m) performed by two subjects.

Sensitivity of loading to the timing of joint kinematic strategies in simulated forefoot impact landings.

The impact loads experienced in landing may be influenced by the joint kinematic strategy used. This study aimed to enhance the understanding of the sensitivity of impact loading to the timing of joint kinematic strategies in simulated forefoot landings. Coordinate and force data of drop landings were used to initiate, drive, and evaluate a wobbling mass model.

Soft tissue contributions to impact forces simulated using a four-segment wobbling mass model of forefoot-heel landings.

The purpose of this investigation was to develop and evaluate a wobbling mass model of a female performing a drop landing and to examine the influence of soft tissue properties on the impact loads experienced. A planar model comprising a foot, shank, thigh and upper body segment was developed. Spring-damper systems coupled the foot to the ground and the wobbling masses to the rigid masses.

Component inertia modeling of segmental wobbling and rigid masses.

A modification to an existing mathematical model is described, which permits the determination of subject-specific inertia parameters for wobbling and rigid masses of female body segments. The model comprises segment-specific soft tissue, bone, and lung components. A total of 59 geometric solids (40 soft tissue, 17 bone, 2 lung) were used to represent the body components.