The V˙O2 response to submaximal ramp cycle exercise: Influence of ramp slope and training status

The aim of the study was to test whether ramp slope and training status interact in the oxygen uptake (V˙O2) response during submaximal ramp exercise. Eight cyclists (V˙O2 peak = 67.8 ± 3.7 ml min−1 kg−1) and eight physically active students (PA students) (V˙O2 peak = 49.1 ± 4.3 ml min−1 kg−1) performed several ramp protocols, respectively, 25 and 40 W min−1 for the cyclists and 10, 25 and 40 W min−1 for the PA students. V˙O2 was plotted as a function of time and work rate up to the gas exchange threshold (GET). Faster ramp elicited a significantly shorter mean response time (MRT) in both groups, and MRT was significantly longer for each ramp protocol in the PA students (126 ± 32 s, 76 ± 15 s and 50 ± 6 s for ramp 10, ramp 25 and ramp 40, respectively) compared to the cyclists (61 ± 9 s and 40 ± 11 s for ramp 25 and ramp 40, respectively). Ramp 40 showed less steep ΔV˙O2/ΔW than ramp 25 in both groups (p < 0.01) and ΔV˙O2/ΔW was less steep for each ramp protocol in PA students (p < 0.01) (9.82 ± 0.30 ml min−1 W−1 and 9.33 ± 0.45 ml min−1 W−1 for ramp 25 and ramp 40, respectively) compared to cyclists (10.31 ± 0.40 ml min−1 W−1 and 10.05 ± 0.48 ml min−1 W−1 for ramp 25 and ramp 40, respectively). In the PA students, ΔV˙O2/ΔW did not differ between ramp 10 and ramp 25. Statistical analysis showed no interaction effects between ramp slope and training status for MRT (p = 0.62) and ΔV˙O2/ΔW (p = 0.35).