Please cite this article as: Mason DL, Preece SJ, Bramah CA, Herrington LC, Reproducibility of kinematic measures of the thoracic spine, lumbar spine and pelvis during fast running, Gait and Posture (2014), http://dx

20Previous research into running has demonstrated consistent patterns in pelvic, lumbar and 21 thoracic motions between different human runners. However, to date, there has been limited 22 attempt to explain why observed coordination patterns emerge and how they may relate to 23 centre of mass (CoM) motion. In this study, kinematic data were collected from the thorax, 24 lumbar spine, pelvis and lower limbs during over ground running in n=28 participants. These

The gait cycle is frequently divided into two distinct phases, stance and swing, which can be accurately determined from ground reaction force data. In the absence of such data, kinematic algorithms can be used to estimate footstrike and toe-off. The performance of previously published algorithms is not consistent between studies. Furthermore, previous algorithms have not been tested at higher running speeds nor used to estimate ground contact times. Therefore the purpose of this study was to both develop a new, custom-designed, event detection algorithm and compare its performance with four previously tested algorithms at higher running speeds. Kinematic and force data were collected on twenty runners during overground running at 5.6m/s. The five algorithms were then implemented and estimated times for footstrike, toe-off and contact time were compared to ground reaction force data. There were large differences in the performance of each algorithm. The custom-designed algorithm provided the most accurate estimation of footstrike (True Error 1.2 ± 17.1 ms) and contact time (True Error 3.5 ± 18.2 ms). Compared to the other tested algorithms, the custom-designed algorithm provided an accurate estimation of footstrike and toe-off across different footstrike patterns. The custom-designed algorithm provides a simple but effective method to accurately estimate footstrike, toe-off and contact time from kinematic data.

Most proposed physiotherapy techniques for rehabilitation of hamstring injuries have not been assessed using randomised trials. Those that have only have single studies with a limited range of participants and outcomes. There is limited evidence to suggest that time to recovery for elite athletes can be reduced with an increased daily frequency of hamstring stretching exercises. There is preliminary evidence from another small study of mixed ability athletes to suggest that exercise to correct movement dysfunction could reduce time to return to full activity and the risk of re-injury. Further studies are required to check these findings. Until further evidence is available, current practice and widely published rehabilitation protocols cannot either be supported or refuted.

The biomechanical profile of high-level endurance runners may represent a useful model that could be used for developing training programmes designed to improve running style. This study therefore sought to compare the biomechanical characteristics of high-performance and recreational runners. Kinematic and kinetic measurements were taken during overground running from a cohort of 14 highperformance (8 male) and 14 recreational (8 male) runners, at four speeds ranging from 3.3 to 5.6 ms-1. Two-way ANOVA analysis was then used to explore group and speed effects and principal component analysis to explore the interdependence of the tested variables. The data showed the high-performance runners to have a gait style characterised by an increased vertical velocity of the centre of mass and a flight time that was 11% longer than the recreational group. The high-performance group were also observed to adopt a forefoot strike pattern, to contact the ground with their foot closer to their body and to have a larger ankle moment. Importantly, although observed group differences were mostly independent of speed, the tested variables showed a high degree of interdependence suggesting an underlying unitary phenomenon. This is the first study to compare high-performance and recreational runners across a full range of kinematic and kinetic variables. The results suggest that high-performance runners maintain stride length with a prolonged aerial phase, rather than by landing with a more extended knee. These findings motivate future intervention studies that should investigate whether recreational runners could benefit from instruction to decrease shank inclination at foot contact.