ECSS Paris 2023: OP-MH45
INTRODUCTION: The use of fast (brisk) walking (FW) has been gaining attention for promotion of health. FW leads to greater energy expenditure with smaller ground reaction force compared to running at same velocity (Makino et al. 2022a, 2022b). On the other hand, the impact of long-term FW training on vascular endothelial function has not been clarified. In previous study, long-term endurance training at low-intensity or middle-intensity caused comparable improvements of FMD (Marinei, 2020), but the use of FW may present further effects. Therefore, the purpose of the present study was to determine the effects of 10 weeks of FW on vascular endothelial function in middle-aged adults. METHODS: Thirty-five participates in middle-aged adults (54.4 ± 11.6 years; FW group: n = 23, Control group: n = 12) were recruited. Participants in the FW group performed fast walking (20-30 min / day, 4 days / week) for 10 weeks, whereas Control group did not perform FW with maintaining regular lifestyle. Before and after 10 weeks of intervention, body composition, vascular endothelial function (assessed by brachial artery flow-mediated vasodilation [FMD]) and blood pressure were evaluated. RESULTS: Average walking velocity in the FW group was 6.8 ± 0.7 km/h, and the average duration was 24.3 ± 3.3 min. After the 10 weeks of intervention, FMD did not change significantly in either FW group (Pre: 5.0 ± 1.7%, Post: 5.6 ± 2.2%) or Control group (Pre: 6.1± 2.5%, Post: 4.8 ± 2.8%, P > 0.05). However, blood pressure was decreased significantly after the intervention in both groups (systolic blood pressure; P = 0.0004, diastolic blood pressure; P = 0.001). CONCLUSION: The walking velocity and duration were thought to be sufficient for improving FMD. However, baseline levels of FMD in the present participants were included in normal range, which may affect the lack of adaptation. It is possible that augmented sympathetic nervous activation during FW caused negative impact for improvement of FMD. In conclusion, 10 weeks of fast walking did not improve vascular endothelial function in middle-aged adults.
Read CV Saaya TaniguchiECSS Paris 2023: OP-MH45
INTRODUCTION: Although zone 1 aerobic training forms the foundation of endurance performance and cardiovascular health promotion, its acute microvascular effects remain poorly understood. Optical coherence tomography angiography (OCT-A) is a non-invasive imaging tool that visualises retinal capillary networks and OCT-A may provide insights into systemic microvascular adaptations during physical activity. However, it remains unclear whether physical stress alters retinal capillary structures and to what extent the eye could be used to monitor whole-body vascular responses. The aim of this study was to determine whether standardized one-hour aerobic threshold running induces detectable structural changes in the retinal and choroidal microvasculature, and to evaluate the potential of OCT-A as a translational imaging biomarker linking ocular and systemic microvascular physiology (n=104 eyes). METHODS: Fifty-two moderately trained recreational runners from (age: 32± 10 years, Yo-Yo test: 933±415 m; VO₂ max: 44.2±3.5 ml/kg/min) completed a one-hour running training session in Zone 1, monitored using Garmin Vivosmart. Lactate analyses were performed before and after the run to evaluate the metabolic state. The superficial capillary plexus (SCP) and choroid were examined immediately before and after training using a Canon Xephilio S1 wide-angle swept-source OCT A (23 × 20 mm²). To extract the flow parameters from the image, Angio Tool software was applied, followed by quantitative analyses using paired t-tests in GraphPad Prism. RESULTS: Individualized Zone 1 running produced moderate aerobic stress, as confirmed by lactate levels (pre: 1.83 mmol/L ± 1.66 vs. post: 2.24 mmol/L ± 2.01; P = 0.22) and heart rate maintenance within the aerobic training zone (average HR: 140 ± 10, minimum HR: 122 ± 14, maximum HR: 157 ± 10). Widefield OCT-A revealed no significant structural capillary remodelling post-exercise. Metrics of the superficial capillary plexus remained stable (all p > 0.11). Corresponding choroidal parameters showed equivalent stability (all p > 0.37). Excellent measurement reproducibility confirmed the robustness of the methodology (pre-post correlations: r = 0.50–0.75; all p < 0.0001). CONCLUSION: Individualized Zone 1 running preserved retinal and choroidal capillary architecture despite verified physiological training stress, demonstrating robust microvascular autoregulation during foundational endurance training. Widefield OCT-A revealed no detectable structural capillary remodeling, establishing the retina as stable reference for exercise microvascular studies. This translational approach validates OCT-A as non-invasive imaging tool to monitor training-induced microvascular adaptations. Future investigations may identify Zone 1 thresholds beyond which retinal capillary remodeling occurs.
Read CV Boris SchmitzECSS Paris 2023: OP-MH45
INTRODUCTION: Children with Duchenne and Becker muscular dystrophies (DMD/BMD) are characterized by progressive muscle weakness, yet concerns about exercise-induced muscle damage often limit engagement in physical activity. Plasma microRNAs (miRNAs) offer a sensitive tool for detecting muscle injury and effort adaptive responses, but data regarding miRNAs response following light aerobic training in dystrophinopathies is limited. The aim of this study was to evaluate pre- and post-training miRNA responses of 12-week light aerobic program in children with dystrophinopathies. METHODS: Thirty children (DMD n=10, BMD n=10, controls n=10) completed a 12-week remote light-aerobic training program. Plasma miRNAs were collected before and after the training period, sequenced on an Illumina NextSeq 500, and analyzed using a standardized pipeline for trimming, UMI-based deduplication, alignment to miRBase v22, and differential expression testing in DESeq2 (padj < 0.1). Functional assessments included the 6MWT, NSAA, hand-held dynamometry, and serum CPK. Between-group comparisons used ANOVA or Kruskal–Wallis tests, and pre-post changes were assessed and analyzed using paired t-tests or Wilcoxon tests (p ≤ 0.05). RESULTS: At baseline, DMD and BMD showed distinct miRNA signatures compared with controls, primarily involving myomiRs, myogenesis, mitochondrial biogenesis, and inflammatory pathways. After training none of the miRNAs associated with muscle degeneration were elevated in these children. After 12 weeks, 26 miRNAs showed significant changes in children with BMD consistent with positive exercise adaptation, including markers of muscle regeneration (e.g., miR-16-2-3p, hsa-miR-451a, hsa-miR-363-3p, has-miR-1, hsa-hsa-miR-143-3p, hsa-miR-27b-3p, hsa-miR-379-5p, hsa-miR-199a-3p and hsa-miR-99b-5p), mitochondrial biogenesis (miR-28-3p, miR-146a-5p), and anti-inflammatory signaling (has-miR-4580, hsa-miR-223-5p, hsa-miR-134-5p, hsa-miR-139-5p, hsa-miR-409-3p, hsa-miR-340-3p, has-miR-432-5p, has-miR-1277-5p, and has-miR-12136). In children with DMD, hsa-miR-133a-5p, hsa-miR-206, hsa-miR-378a-5p, miR-744-5p, and hsa-miR-4508 miRNAs demonstrated similar non-significant trends. Functionally, physical activity adherence was high across groups during the study period, with DMD completing shorter and slower sessions but demonstrating comparable cardiovascular responses. Functional capacity remained stable over 12 weeks (6MWT, NSAA, quadriceps; all p>0.05), while hamstring strength improved in both DMD (p=0.045) and BMD (p=0.02). CPK levels and exertional CPK ratios remained unchanged, reinforcing training safety. CONCLUSION: These findings suggest that short term light aerobic training is feasible, safe, and elicits beneficial molecular adaptations in children with dystrophinopathies.
Read CV Itai GoldfarbECSS Paris 2023: OP-MH45