|Getting ready for an all-out sprint? A bitter mouth rinse W/ quinine will provide instant power boost of 4% in ‘ur 30s cycle sprint more than a sweet mouth rinse could do .|
Against that background and in view of the similar brain activation patterns scientists have observed in response to bitter and sweet taste perception, it appears only logical for Sharon Gam et al. to speculate in a 2014 paper, which is still worth its own SuppVersity article (!), that rinsing w/ quinine, a distinctly bitter substance, could produce the same or at least similar power increments as sweet substances.Of the latter, previous research has shown that they will elevate both peak power (+22.1 ± 19.5 W; ES, 0.81; p = 0.0667) and mean power (+39.1 ± 26.9 W; ES, 1.08; p = 0.0205 | Beaven, et al. 2013), during all out sprints. The goal of the researchers from the University of Western Australia was thus to elucidate, "whether combining mouth rinsing with the ingestion of a bitter-tasting solution composed of quinine acutely improves mean and peak power during a 30-s maximal cycling sprint effort" (Gam. 2016) would yield similar benefits.
To be able to tell how similar sweet and bitter taste effects on sprinting performance actually are, they scientists compared the effects of 0.36 mL/kg body mass of a 2-mM quinine HCl solution (QUI; Sigma-Aldrich), not just to plain water and a no rinse control (CON), but also to a 0.05% w/v aspartame solution (ASP; Sigma-Aldrich), all of which were used immediately before the 30s all-out sprint on an Exertech EX-10 front access cycle ergometer.
|Figure 1: My graphical "illustration" of the study design (based on facts from Gam. 2014).|
|Bitter perception (Mennella. 2013).|
|Figure 2: Relative changes in mean & peak power (%) + effects sizes for quinine vs. CON, WAT or ASP (Gam. 2014).|
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