Author(s): HEANEY, R., BUYS, P., TEALE, J.E., CURTIN, E.L., WESTON, M.E., EGAÑA, M., GILDEA, N., Institution: TRINITY COLLEGE DUBLIN, Country: IRELAND, Abstract-ID: 2703

INTRODUCTION:
Suspension training is a contemporary form of resistance exercise that utilises body weight and adjustable straps to develop balance, control, and core strength. Its' versatility and scalability make it accessible to a wide range of fitness levels, contributing to its growing popularity in recent years. Despite this, the acute effects of suspension exercise on the cerebral vasculature remain underreported. This study investigated the effects of a single bout of suspension training on cerebrovascular reactivity (CVR), a key indicator of vascular function and cerebrovascular health, in healthy young adults, with responses assessed following hypercapnic and hypocapnic stimuli.
METHODS:
15 healthy young adults (mean age= 23.3 ± 3 years, V̇O₂max 43.9±9.2 ml/kg/min, BMI 22.3±3.9kg/m2) [ME1.1]volunteered to participate in this study and underwent two time-matched visits: a 30-minute suspension training session consisting of five different exercises performed in a circuit format, and a 30-minute control condition (seated rest). CVR was assessed at baseline, 10, and 60 min post-exercise. Transcranial Doppler Ultrasound measured middle cerebral artery blood velocity (MCAv). End-tidal Carbon Dioxide (PETCO2) was measured by a gas analyser. Hypercapnic CVR was quantified as the absolute change in MCAv per mmHg change in PETCO₂ during 4 minutes of inhaling 6% CO₂. Hypocapnic CVR was evaluated during 1 minute of voluntary hyperventilation at 25 breaths·min⁻¹, with changes in MCAv and PETCO₂ calculated from the final 10 seconds. Differences in CVR were assessed using a 2-way repeated measures ANOVA.
RESULTS:
Baseline MCAv did not differ by condition (P=0.785), time (P=0.524), or time x condition interaction (P=0.650). CVR in response to hypercapnia showed a significant main effect of time (P=0.029), but no effect of condition (P=0.686) nor a time x condition interaction (P=0.143). Pairwise comparisons revealed that CVR to hypercapnia [ME2.1]was unchanged 10 minutes post-suspension exercise compared with baseline (P=0.116), but was reduced at 60 minutes relative to 10 minutes post-exercise (P=0.015). No significant effects of time (P=0.526), condition (P=0.736), or time x condition interaction (P=0.445) were observed for CVR in response to the hypocapnic stimulus.
CONCLUSION:
These findings indicate that a single bout of suspension exercise may elicit transient alterations in hypercapnic CVR in healthy young adults, while hypocapnic CVR responses remained preserved. This differential response suggests a selective influence of acute suspension exercise on vasodilatory capacity rather than on vasoconstrictive regulation in young healthy adults.