Rowing exercise increases cardiorespiratory fitness and brachial artery diameter but not traditional cardiometabolic risk factors in spinal cord-injured humans

Purpose This study assessed the effects of upper body rowing exercise on cardiorespiratory fitness, traditional cardiometabolic
risk factors, and vascular health in individuals with spinal cord injury (SCI).
Methods Seventeen male and female adults with chronic (> 1 yr) motor-complete and incomplete SCI (level of injury:
C4-L3) were randomized to control (CON, n = 9) or exercise (UBROW, n = 8). Participants in UBROW performed 12-week,
3 weekly sessions of 30-min upper body ergometer rowing exercise, complying with current exercise guidelines for SCI.
Cardiorespiratory fitness ( ̇ VO2peak), traditional risk factors (lipid profile, glycemic control) as well as inflammatory and
vascular endothelium-derived biomarkers (derived from fasting blood samples) were measured before and after 6 (6W)
and 12 weeks (12W). Brachial artery resting diameter and flow-mediated dilation (FMD) were determined by ultrasound as
exploratory outcomes.
Results UBROW increased ̇ VO2peak from baseline (15.1 ± 5.1 mL/kg/min; mean ± SD) to 6W (16.5 ± 5.3; P < 0.01) and
12W (17.5 ± 6.1; P < 0.01). UBROW increased resting brachial artery diameter from baseline (4.80 ± 0.72 mm) to 12W
(5.08 ± 0.91; P < 0.01), with no changes at 6W (4.96 ± 0.91), and no changes in CON. There were no significant time-bygroup
interactions in traditional cardiometabolic blood biomarkers, or in unadjusted or baseline diameter corrected FMD.
Explorative analyses revealed inverse correlations between changes (Δ12W-baseline) in endothelin-1 and changes in resting
diameter (r = − 0.56) and FMD% (r = − 0.60), both P < 0.05.
Conclusion These results demonstrate that 12 weeks of upper body rowing complying with current exercise guidelines for
SCI improves cardiorespiratory fitness and increases resting brachial artery diameter. In contrast, the exercise intervention
had no or only modest effects on traditional cardiometabolic risk factors. The study was registered at Clinicaltrials.gov
(N-20190053, May 15, 2020).