Heavy-intensity priming exercise extends the V̇ O2max plateau and increases peak-power output during ramp-incremental exercise

This study investigated whether a heavy-intensity priming exercise precisely prescribed within the heavy-intensity domain would lead to a greater peak-power output (POpeak) and a longer maximal oxygen uptake (V̇ O2max) plateau. Twelve recreationally active adults participated in this study. Two visits were required: 1) a step-ramp-step test [ramp-incremental (RI) control], and 2) an RI test preceded by a priming exercise within the heavy-intensity domain (RI primed). A piecewise equation was used to quantify the V̇ O2 plateau duration (V̇ O2plateau-time). The mean response time (MRT) was computed during the RI control condition. The delta (D) V̇ O2 slope (S; mL·min-1·W-1) and V̇ O2-Y intercept (Y; mL·min-1) within the moderate-intensity domain between conditions (RI primed minus RI control) were also assessed using a novel graphical analysis. V̇ O2plateau-time (P = 0.001; d = 1.27) and POpeak (P = 0.003; d = 1.08) were all greater in the RI primed. MRT (P < 0.001; d = 2.45) was shorter in the RI primed compared with the RI control. A larger DV̇ O2plateau-time was correlated with a larger DMRT between conditions (r = –0.79; P = 0.002). This study demonstrated that heavy-intensity priming exercise lengthened the V̇ O2plateau-time and increased POpeak. The overall faster RI-V̇ O2 responses seem to be responsible for the longer V̇ O2plateau-time. Specifically, a shorter MRT, but not changes in RI-V̇ O2slopes, was associated with a longer V̇ O2plateau-time following priming exercise. NEW & NOTEWORTHY It remains unclear whether priming exercise extends the maximal oxygen uptake (V̇ O2max) plateau and increases peak-power output (POpeak) during ramp-incremental (RI) tests. This study demonstrates that a priming exercise, precisely prescribed within the heavy-intensity domain, extends the plateau at V̇ O2max and leads to a greater POpeak. Specifically, the extended V̇ O2max plateau was associated with accelerated RI-V̇ O2 responses.