Cardio-pulmonary responses to incremental eccentric and concentric cycling tests to task failure.

Abstract

This study compared cardio-pulmonary responses between incremental concentric and eccentric cycling tests, and examined factors affecting the maximal eccentric cycling capacity. On separate days, nine men and two women (32.6 ± 9.4years) performed an upright seated concentric (CON) and an eccentric (ECC) cycling test, which started at 75W and increased 25Wmin-1 until task failure. Gas exchange, heart rate (HR) and power output were continuously recorded during the tests. Participants also performed maximal voluntary contractions of the quadriceps (MVC), squat and countermovement jumps. Peak power output was 53% greater (P < 0.001, g = 1.77) for ECC (449 ± 115W) than CON (294 ± 61W), but peak oxygen consumption was 43% lower (P < 0.001, g = 2.18) for ECC (30.6 ± 5.6mlkgmin-1) than CON (43.9 ± 6.9mlkgmin-1). Maximal HR was not different between ECC (175 ± 20bpm) and CON (182 ± 13bpm), but the increase in HR relative to oxygen consumption was 33% greater (P = 0.01) during ECC than CON. Moderate to strong correlations (P < 0.05) were observed between ECC peak power output and CON peak power (r = 0.84), peak oxygen consumption (r = 0.54) and MVC (r = 0.53), while no significant relationships were observed between ECC peak power output and squat as well as countermovement jump heights. Unexpectedly, maximal HR was similar between CON and ECC. Although ECC power output can be predicted from CON peak power output, an incremental eccentric cycling test performed after 3-6 familiarisation sessions may be useful in programming ECC training with healthy and accustomed individuals.