A single bout of submaximal aerobic functional capacity test acutely increased brachial artery endothelial function (FMD% increased from 4.53% to 6.83%, p=0.0005) in individuals with long COVID compared to baseline, though post-test FMD remained lower than healthy controls (6.83% vs 10.07%, p=0.0021).
Observational (n=47)
No
Does a single bout of submaximal aerobic functional capacity test (6MST) acutely improve brachial artery endothelial function in adults with long COVID?
A single bout of submaximal aerobic exercise via the 6-minute step test acutely improves endothelial function in patients with long COVID, though it does not normalize to healthy control levels.
Effect estimate: Cohen's d 1.038 for increase in COVID group pre- to post-6MST; Cohen's d 1.356 for difference between groups post-6MST
Absolute Event Rate: 6.83% vs 10.07%
p-value: p=0.0005 for within COVID group increase; 0.0021 for between groups post 6MST difference
Persistent symptoms and vascular impairment are common among individuals recovering from COVID-19, yet little is known about acute interventions capable of improving endothelial function in this group. Submaximal functional tests, such as the six-minute step test (6MST), provoke marked cardiovascular activation and may provide a brief stimulus for vascular adaptation. This study examined whether performing a single 6MST session could trigger an immediate enhancement in brachial artery endothelial function in adults with long COVID. Forty-seven participants, symptomatic long COVID individuals and healthy controls, underwent evaluations of respiratory function, fatigue, dyspnoea, habitual physical activity, and functional capacity. Cardiorespiratory responses during the 6MST were measured with a portable metabolic system, and flow-mediated dilation (FMD) of the brachial artery was assessed before exercise and 10–15 min afterward. At baseline, the long COVID group demonstrated greater adiposity, a higher burden of comorbidities, reduced functional capacity, lower peak V̇O2, and attenuated FMD relative to controls. A single bout of submaximal test acutely improves brachial artery endothelial function in individuals with persistent symptoms following COVID-19. These participants also displayed reduced functional capacity and peak VO2, greater diastolic blood pressure response, and increased lower limb fatigue during the test. Although VO2 peak showed a modest association with the FMD% response in univariate analysis, this relationship did not persist after adjustment for confounders, indicating that the acute vascular improvement was not independently determined by cardiorespiratory fitness.
Santos-de-Araújo et al. (Wed,) conducted a observational in Long COVID (n=47). Single bout of submaximal aerobic functional capacity test (six-minute step test, 6MST) vs. Healthy controls (no persistent symptoms, no recent COVID-19) was evaluated on Change in brachial artery flow-mediated dilation (FMD %) from pre- to post-6MST (Cohen's d 1.038 for increase in COVID group pre- to post-6MST; Cohen's d 1.356 for difference between groups post-6MST, p=0.0005 for within COVID group increase; 0.0021 for between groups post 6MST difference). A single bout of submaximal aerobic functional capacity test acutely increased brachial artery endothelial function (FMD% increased from 4.53% to 6.83%, p=0.0005) in individuals with long COVID compared to baseline, though post-test FMD remained lower than healthy controls (6.83% vs 10.07%, p=0.0021).