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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 o 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 V̇ o 2 plateau duration (V̇ o 2plateau-time). The mean response time (MRT) was computed during the RI control condition. The delta (Δ) V̇ o 2 slope (S; mL·min−1·W−1) and V̇ o 2-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 o 2plateau-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 ΔV̇ o 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 V̇ o 2plateau-time and increased POpeak. The overall faster RI-V̇ o 2 responses seem to be responsible for the longer V̇ o 2plateau-time. Specifically, a shorter MRT, but not changes in RI-V̇ o 2-slopes, was associated with a longer V̇ o 2plateau-time following priming exercise. NEW & NOTEWORTHY: It remains unclear whether priming exercise extends the maximal oxygen uptake (V̇ o 2max) 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 o 2max and leads to a greater POpeak. Specifically, the extended V̇ o 2max plateau was associated with accelerated RI-V̇ o 2 responses. [ABSTRACT FROM AUTHOR]

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 V̇o 2 plateau duration (V̇o 2plateau-time ). The mean response time (MRT) was computed during the RI control condition. The delta (Δ) V̇o 2 slope (S; mL·min -1 ·W -1 ) and V̇o 2 -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-V̇o 2 responses seem to be responsible for the longer V̇o 2plateau-time . Specifically, a shorter MRT, but not changes in RI-V̇o 2 -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-V̇o 2 responses.

This study aimed to investigate the effects of chronic β-alanine (βA) plus acute sodium bicarbonate (SB) co-supplementation on neuromuscular fatigue during high-intensity intermittent efforts in swimming. Eleven regional and national competitive-level young swimmers performed a neuromuscular fatigue assessment before and immediately after two 20 × 25-m front crawl maximal efforts every 90 s, performed at pre- and post-4-week co-supplementation. Neuromuscular fatigue was evaluated by percutaneous electrical stimuli through the twitch interpolation technique on the triceps brachii and quadriceps femoris . Performance was defined by the mean time of the 20 efforts and blood samples to lactate concentrations were collected every four efforts. Participants supplemented 3.2-6.4 g·day -1 of chronic βA or placebo (PL) during four weeks, and acute 0.3 g·kg -1 of SB or PL 60 min before the second assessment (allowing βA+SB and PL+PL groups). No statistical changes were found in neuromuscular fatigue of triceps brachii . In the quadriceps femoris , a main effect of time was found in potentiated twitch delta values in pooled groups, showing a statistical increase of 19.01% after four weeks (Δ = 13.05 [0.35-25.75] N; p = 0.044), without time × group interactions. No statistical difference was found in the swimming performance. Blood lactate increased by 25.06% only in the βA+SB group (Δ = 6.40 [4.62-8.18] mM; p Bonf < 0.001) after the supplementation period. In conclusion, 4-week βA and SB co-supplementation were not able to reduce neuromuscular fatigue levels and improve performance in highintensity intermittent efforts, but statistically increased blood lactate levels.