Browsing by Author "Macdermid PW"

Now showing 1 - 4 of 4
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    Evaluating the Usefulness of a PNT Solution Using DGNSS-SBAS for Canoe Slalom: Simulated and Real-World Analysis
    (MDPI (Basel, Switzerland), 2024-11-18) Macdermid PW; Irwin ME; Cochrane D; Daniel M-L
    Featured Application: dGNSS-SBAS combined with geographical mapping software and georeferenced drone imagery is a cutting-edge approach to geographically track activities pertaining to canoe slalom. The PNT solution provided <0.3 m accuracy and provided a reliable means of tracking athletes’ trajectory, which could be used to monitor or develop best practice in athlete trajectories. This study investigated the accuracy and precision of a commercially available PNT solution that uses DGNSS-SBAS technology. Time and position data were sampled at a frequency of 20Hz during both a short and long trajectory of a simulated controlled dry-land slalom, as well as during a real-world on-water slalom exercise. The primary objective was to assess the positional accuracy, availability, integrity, and service continuity of the PNT solution while evaluating its ability to differentiate between trajectories. Additionally, the simulated results were compared with an on-water real-world slalom test to validate the findings. The results of the controlled dry-land slalom test indicate that the PNT solution provided accurate measurements with an overall mean ± SD Hrms of 0.20 ± 0.02 m. The integrity measures, HDOD and PDOP, were found to be ideal to excellent, with values of 0.68 ± 0.03 and 1.36 ± 0.07, respectively. The PNT solution utilised an average of 20 ± 1 satellites from the constellation, resulting in an accuracy of <1.5% when measuring the known trajectory of 50 simulated slalom runs. The data from the real-world on-water slalom test supported these findings, providing similar or improved results. Based on these findings, a PNT solution using DGNSS-SBAS can be considered an effective means of tracking athlete trajectory in the sport of canoe slalom. Future research should be conducted to quantify its efficacy more precisely.
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    The Effects of Cushioning Properties on Parameters of Gait in Habituated Females While Walking and Running
    (MDPI (Basel, Switzerland), 2025-01-23) Macdermid PW; Walker SJ; Cochrane D; Voloshin A
    Featured Application: Understanding the interaction between running shoe properties and parameters of gait are somewhat scarce, particularly in female runners. This study demonstrates that contrasting energy absorption properties reduce kinetic variables associated with injuries in females while running, but not walking. The purpose of this study was to compare the mechanical properties of a non-cushioned minimalistic shoe and cushioned shoe during walking at 6 and running at 10 and 14 km∙h−1 in habituated female runners. Twelve habituated female runners completed two trials (cushioned shoe vs. minimalist shoe) with three within-trial speeds (6, 10, and 14 km∙h−1) in a counter-balanced design. Flexible pressure insole sensors were used to determine kinetic variables (peak vertical impact force, average loading rate, active vertical peak force, time to active peak vertical force, and impulse) and spatiotemporal variables (stride duration, cadence, ground contact time, swing time, and time to midstance). Cushioned running shoes exhibited greater energy absorption (690%), recovered energy (920%), and heat dissipation (350%). The cushioned shoes significantly reduced peak vertical impact (~12%) and average loading rate (~11%) at running speeds 10–14 km∙h−1. However, these effects were not observed during walking, nor did the cushioned shoes influence peak active force, impulse, stride duration, ground contact or swing time. Cushioned running shoes provide significant benefits in energy absorption, energy recovery, and heat dissipation, which decrease impact-related forces and loading rates in female runners without changing the spatiotemporal variables of gait.
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    The Relationship between Stroke Metrics, Work Rate and Performance in Slalom Kayakers
    (MDPI (Basel, Switzerland), 2022-01-28) Macdermid PW; Olazabal T; Keogh J; Hortobagyi T
    The purpose of this study was to assess the relationship between work rate, stroke metrics, and performance in whitewater slalom. Twelve Spanish, nationally competitive whitewater slalom kayakers took part in a simulated competition while using an instrumented kayak paddle to record stroke metrics over a simulated race, total duration and sectional splits. Performance time was highly correlated to overall power output (r2 = 0.511, p < 0.001), where kayakers demonstrated a positive pacing strategy with power output significantly decreasing over successive sectional splits (158 ± 40, 112 ± 32 and 65 ± 33 W, p < 0.001). This resulted in an increased stroke duration (p < 0.001), time to peak force (p < 0.001), a decrease in stroke peak force (p < 0.001), and rate of peak force development (p < 0.001) over elapsed time. As such, work rate is deemed an objective metric to monitor performance, prescribe training, and ascertain optimal pacing strategies in canoe slalom.
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    The Validity and Reliability of a Global Navigation Satellite System in Canoe Slalom
    (MDPI (Basel, Switzerland), 2022-01-21) Macdermid PW; Coppelmans A; Cochrane D; Keogh J
    This study investigates the usefulness of a 10 Hz GPS device for tracking scalar performance in canoe slalom through assessing the validity of automated-informed-aerial video tracking (30 fps and 10 fps) and GPS capability in relation to a known track. Additionally, a real-world (canoe-slalom). A comparison between manual-aerial video tracking (10 fps) and the 10 Hz GPS was performed. All three methods of tracking used during the dry-land test (30 fps or 10 fps video and GPS) reported significantly lower distances (−3.2, −5.1 and −8.5%, p < 0.0001) but were deemed useful based on sample rate and body positioning difference. Intra-method reliability was good (CV = 2.5−2.6%) but requires visual inspection for dataset errors. Informed-colour filtered automated tracking on-water was not possible, but manual tracking provided fewer dataset errors than dry-land automated tracking. GPS significantly (p < 0.0001) under reports distance travelled at key moments during real-world slalom with a bias ± SD of 2.26 ± 2.07 m compared to 10 fps manual-aerial video tracking. The aerial video combined with manual tracking proved most suitable for tracking canoe slalom athlete trajectory in a real-world setting but needs to be automated into an application-based package to make it useable for coaches. GPS, as presented, provides insight but does not accurately quantify movements critical in determining the performance of canoe slalom.