Search Results (3)

Trail running imposes highly variable biomechanical demands due to steep, irregular terrain that renders flat-road pacing models inadequate. We present a physics-based digital twin that integrates a terrain-adaptive grade-adjusted pace (GAP) model with individualised physiological calibration to predict finish time across heterogeneous trail-running races. The GAP core applies Minetti’s fifth-degree metabolic cost polynomial to map slope-dependent energy cost across the full range of uphill and downhill gradients encountered in trail racing. Segment-by-segment pace is further modulated by an altitude–VO₂max correction, a Banister TRIMP-based fatigue term, and a progressive pacing-decay factor. Course-elevation profiles are extracted from 1 Hz barometric altimeter data through a five-step normalisation pipeline. Individual parameters (sustainable VT₂ fraction α; pacing-decay slope μ) were calibrated by grid search against 13 race sessions. A sequential validation across four model-complexity stages showed R² increasing from 0.763 to 0.905. Leave-one-out cross-validation (n = 13) yielded R² = 0.864, MAE = 18.2 min, MAPE = 11.1%, and a small positive bias (+2.0 min). The framework demonstrates that integrating biomechanical terrain correction with individual physiological calibration substantially improves race-time prediction for trail running, offering a promising foundation for athlete-specific pre-race simulation. Full article

Background and Objectives: Relapsed or refractory germ cell tumors are commonly treated with HDCT/ASCT, but robust predictors of hematopoietic recovery are limited. Quantitative CT-based metrics of body composition are readily available, but their prognostic value for post-transplant engraftment remains uncertain. We investigated whether muscle and fat indices derived from routine CT scans are associated with the pace of hematologic recovery after HDCT/ASCT. Materials and Methods: This retrospective study analyzed a single-center cohort (n = 43) with relapsed/refractory GCT undergoing HDCT/ASCT. CT within 6 months pre-HDCT/ASCT was analyzed at L3 to derive the Skeletal muscle index, Psoas muscle index, Subcutaneous fat area, Visceral fat area, Total fat area, Visceral-to-subcutaneous fat area ratio. Primary endpoint: The engraftment time post-ASCT. Spearman’s ρ was used for univariable associations; multivariable linear regressions were adjusted for age, Hb, weight, and BSA to evaluate the independent effects. The significance was set at p < 0.05. Results: The median hematologic engraftment duration was 12.0 days, and the engraftment duration was positively correlated with age and negatively with hemoglobin. According to the multivariable analysis, older age and lower hemoglobin independently predicted longer engraftment; body weight and BSA were not significant. Among the morphometrics, only the VFA/SFA ratio was associated with delayed engraftment. The SMI, PMI, and TFA were not significant. As expected, after HDCT, grade 4 neutropenia and thrombocytopenia occurred in all patients. Conclusions: In relapsed/refractory GCT treated with HDCT/ASCT, older age and lower post-transplant hemoglobin independently predicted a prolonged engraftment. Beyond traditional muscle/fat areas, a higher VFA/SFA ratio—reflecting visceral adiposity—is also associated with delayed recovery, suggesting that fat distribution may influence hematopoietic regeneration. These variables may support pre-transplant risk stratification and individualized supportive care. Full article

Para swimmers categorized as S10 and S12 are of particular interest due to their disability grading being closest to that of able-bodied swimmers, making them an ideal group for investigating disparities in limb coordination patterns. This study aimed to investigate whether S10 and S12 para swimmers, whose disability grading for movement and visual ability, respectively, were the closest to that of able-bodied swimmers, would differ in terms of the biomechanics of limb coordination. This study recruited twenty para swimmers (ten with minor limb absence (S10) in the hand and ten with minor visual impairment (S12)). Using panoramic video, the phase duration, stroke length, stroke rate, index of coordination, synchronization, and inter-limb coordination were digitized and compared in the context of a front-crawl sprinting test. The results showed a significantly different duration of the recovery phase for S10 para swimmers at the affected side, where a more random coordination pattern between arm and leg at the pull and push phases was statistically seen. The variation of the inter-limb coordination gradually increased for S10 para swimmers from hand entry to the end of push, but gradually reduced for S12 para swimmers. These results suggest that the same pace was achieved by different hand–leg coordination patterns according to their physical constraints. Consequently, the unique coordination patterns of different para swimmers from this study offer an opportunity to explore the adaptive strategies and biomechanical adjustments that enable optimal performance for para swimmers. Full article