Mouth Rinsing Cabohydrates Serially does not Improve Repeated Sprint Time

Abstract

Sensing carbohydrates via the oral cavity benefits performance outcomes during brief high intensity bouts of exercise. However, the extent to which carbohydrates need to be present in the oral cavity to influence sprint performance is less understood. The purpose of this study was to determine if serial increases in carbohydrate rinse time across sprint sets attenuates increases in sprint time compared to no serial increases in carbohydrate rinse time across sprint sets. Fifteen sprint trained participants completed three repeated anaerobic sprint tests (RAST), 3 sets of 6 x 35-m sprints, under two different carbohydrate mouth rinsing (CMR) conditions; (1) rinsing for only 5 seconds (s), and (2) rinsing for 5 s, 10 s and 15 s (serial rinse). Prior to a RAST, participants provided perceived recovery status (PRS) and perceived feeling of arousal (FAS). Upon completion of each individual sprint, participants gave a rating of perceived exertion (RPE). A lactate sample was taken upon completion of each individual sprint set and after all 3 RASTs a session rating of perceived exertion (S-RPE) was measured. There were no significant differences in peak (p = 0.18) and average sprint time (p = 0.41). There were no significant differences in perceptual measures: RPE, PRS, FAS, S-RPE or for blood lactate concentration between CMR conditions. Overall, serial rinsing resulted in changes that were most likely trivial, but showed a 50% chance in perceiving a sprint session as less difficult. Rinsing carbohydrates in a serial manner between repeated sprint sets produces trivial changes of sprint speed and perceptual measures from sprint performance.

Carbohydrate Mouth Rinse Increases High but Not Low Intensity Repetitions to Failure in Resistance-Trained Males

“…In addition, 10 s of CMR was superior to 5 s during 30 min of self-paced cycling performance [31]. In contrast, high-intensity sprinting [32] and a Yo-Yo intermittent recovery test [33] performance did not increase with serial rinsing of CHO (30 and 80 s, respectively). Previously, three studies [20,25,26] from our laboratory observed no improvement in 40% of bench press 1 RM repetition to failure performance with serial CHO rinsing (20 or 30 s).…”

Carbohydrate Mouth Rinse Decreases Time to Complete a Simulated Cycling Time Trial

“…Sinclair et al (18) reported that cycling performance was improved by doubling the duration (from 5 to 10 s) of the carbohydrate mouth rinse protocol, although their results were recently contradicted by Tomko (36) who found no dose-response effect when increasing the rinse duration from 5 to 15 s. Although more evidence is needed to ascertain the optimal rinsing time, it has been suggested that increasing rinsing duration may interfere with participants’ breathing patterns during high intensity exercise (34), as we found in our familiarization trial. Based on the information available so far, carbohydrate mouth rinsing for 5 s, each 5–10 min of exercise, allows for a significant contact between oral cavity and a carbohydrate source.…”

A Narrative Review of Current Concerns and Future Perspectives of the Carbohydrate Mouth Rinse Effects on Exercise Performance

“…Moreover, the use of an exercise protocol that elicited peripheral rather than central fatigue may also have surrendered an additional difficulty to reveal the true CHO mouth rinse effects. 78 Indeed, a recent study by Nehme et al 81 found no benefits in performance measured in the Yo-Yo Intermittent Recovery Test Level 1 with serial CHO mouth rinses. Interestingly, neither serial nor single CHO mouth rinses exhibited superior beneficial effects than placebo mouth rinses.…”

“…Perhaps, the CHO mouth rinse duration has been one of the first methodological aspects highlighted as a confounding factor in the literature. However, only a few studies 26 , 46 , 78 , 79 have attempted to verify the influence of longer mouth rinses with CHO solution on exercise performance.…”

“…Accordingly, Tomko et al 78 verified if serial CHO mouth rinses produced higher improvements in sprint performance than single, isolated rinses. Participants performed three sets of repeated anaerobic sprint tests (6 x 35 m sprints interspersed by 7 min between them) either rinsing their mouth with a single rinse for 5s before the sprint test or rinsing their mouth with multiple 5, 10, and 15s rinses (before the first, second, and third sets of the sprint test, respectively).…”