The VO2 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 (VO2) response during submaximal ramp exercise. Eight cyclists (VO2 peak=67.8+/-3.7 ml min(-1)kg(-1)) and eight physically active students (PA students) (VO2 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. Vo(2) 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+/-32s, 76+/-15s and 50+/-6s for ramp 10, ramp 25 and ramp 40, respectively) compared to the cyclists (61+/-9s and 40+/-11s for ramp 25 and ramp 40, respectively). Ramp 40 showed less steep Delta VO2/Delta W than ramp 25 in both groups (p<0.01) and Delta VO2/Delta W 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, Delta VO2/Delta W 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 Delta VO2/Delta W (p=0.35).