Submaximal, Low-Dose Eccentric vs Traditional Cycling Exercise: Reduced Oxygen Uptake and Pulmonary Artery Pressure Assessed by Echocardiography in Healthy Middle-aged Adults. A Randomized Controlled, Crossover Trial

To investigate the ventilatory and circulatory differences between eccentric (ECC) and concentric (CON) cycling exercise at submaximal, low-dose intensity from onset to end-exercise in healthy middle-aged participants. Randomized controlled crossover trial. The participants underwent 1 ECC and 1 CON test according to stepwise incremental exercise protocols at identical, submaximal intensities. Breath-by-breath analyses of ventilatory gas exchange and echocardiography were used to assess cardiopulmonary function during exercise. 24 healthy middle-aged, untrained participants (14 women, 10 men, 50±14 years) were included. 1 ECC and 1 CON test at submaximal intensities. The main outcome was oxygen uptake (V'O2). The V'O2 increase was reduced by -422 mL/min (-52%, 95% confidence interval: -513 to -292, P