Heavy-intensity priming exercise extends the V̇o2max 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 (PO_peak) and a longer maximal oxygen uptake (V̇o_2max) 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 V̇o₂ plateau duration (V̇o_{2plateau-time}). The mean response time (MRT) was computed during the RI control condition. The delta (Δ) V̇o₂ slope (S; mL·min^-1·W^-1) and V̇o₂-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. V̇o_{2plateau-time} (P = 0.001; d = 1.27) and PO_peak (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 ΔV̇o_{2plateau-time} was correlated with a larger ΔMRT between conditions (r = -0.79; P = 0.002). This study demonstrated that heavy-intensity priming exercise lengthened the V̇o_{2plateau-time} and increased PO_peak. The overall faster RI-V̇o₂ responses seem to be responsible for the longer V̇o_{2plateau-time}. Specifically, a shorter MRT, but not changes in RI-V̇o₂-slopes, was associated with a longer V̇o_{2plateau-time} following priming exercise.NEW & NOTEWORTHY It remains unclear whether priming exercise extends the maximal oxygen uptake (V̇o_2max) plateau and increases peak-power output (PO_peak) during ramp-incremental (RI) tests. This study demonstrates that a priming exercise, precisely prescribed within the heavy-intensity domain, extends the plateau at V̇o_2max and leads to a greater PO_peak. Specifically, the extended V̇o_2max plateau was associated with accelerated RI-V̇o₂ responses.