Mouth Rinsing with Maltodextrin Solutions Fails to Improve Time Trial Endurance Cycling Performance in Recreational Athletes

Abstract

The carbohydrate (CHO) concentration of a mouth rinsing solution might influence the CHO sensing receptors in the mouth, with consequent activation of brain regions involved in reward, motivation and regulation of motor activity. The purpose of the present study was to examine the effects of maltodextrin mouth rinsing with different concentrations (3%, 6% and 12%) after an overnight fast on a 20 km cycling time trial performance. Nine recreationally active, healthy males (age: 24 ± 2 years; V˙O2max: 47 ± 5 mL·kg−1·min−1) participated in this study. A double-blind, placebo-controlled randomized study was conducted. Participants mouth-rinsed every 2.5 km for 5 s. Maltodextrin mouth rinse with concentrations of 3%, 6% or 12% did not change time to complete the time trial and power output compared to placebo (p > 0.05). Time trial completion times were 40.2 ± 4.0, 40.1 ± 3.9, 40.1 ± 4.4, and 39.3 ± 4.2 min and power output 205 ± 22, 206 ± 25, 210 ± 24, and 205 ± 23 W for placebo, 3%, 6%, and 12% maltodextrin conditions, respectively. Heart rate, lactate, glucose, and rating of perceived exertion did not differ between trials (p > 0.05). In conclusion, mouth rinsing with different maltodextrin concentrations after an overnight fast did not affect the physiological responses and performance during a 20 km cycling time trial in recreationally active males.

Carbohydrate Mouth Rinse Fails to Improve Four-Kilometer Cycling Time Trial Performance

“…In this perspective, cyclists of different competitive levels make use of nutritional supplements to improve performance, and anecdotal data suggest that recreational cyclists are among the group of individuals that have frequently used this strategy to improve performance on both training and competition settings. To the best of our knowledge, however, only a few studies have focused on the potential benefits of CHO mouth rinse during typical cycling time trials [ 3 , 9 ]. Accordingly, most of the studies have focused on 1-h time trials [ 2 , 6 , 10 ] instead of distance-based ones such as 4 km, 20 km and 40 km, which would properly resemble competition scenarios.…”

“…In this regard, a recent study verified that CHO mouth rinse did not improve 40-km cycling time trial performance under hyperthermia [ 11 ], while others reported otherwise in 20-km cycling time trials performed in normothermia [ 3 , 9 ]. However, there is paucity of data on the effects of CHO mouth rinse on shorter-lasting trials such as 4 km (TT 4km ).…”

“…However, there is paucity of data on the effects of CHO mouth rinse on shorter-lasting trials such as 4 km (TT 4km ). Although most cycling literature has focused on long- (i.e., 40 km and 20 km) [ 3 , 9 , 11 , 12 ] as well as short-lasting time trials (TT 4km ) [ 13 , 14 ] when investigating manipulations to potentiate cycling performance, evidence for the potential benefit of the CHO mouth rinse in short-lasting cycling time trial performance has yet to be provided. For example, a previous study reported that CHO mouth rinse attenuated global fatigue in an endurance cycling trial, despite the unchanged performance.…”

Repeated-sprints exercise in daylight fasting: carbohydrate mouth rinsing does not affect sprint and reaction time performance

“…Within fasted participants simple strategies such as mouth rinsing (MR) with either Carbohydrate (CHO) or water have shown efficacy to acquiesce some of the fasting induced endurance [ 4 ] and high-intensity [ 5 ] exercise performance decrements. Performance improvements through CHO-MR is dependent on several debated factors, including the fasted or fed state of participants [ 6 ], a dose response to the duration of MR (5 or 10 s [ 7 ]), concentration of the CHO rinse, the rinsing frequency [ 8 ] and the exercise mode [ 9 ]. Positive effects are principally attributed to orally-mediated activation of brain regions associated with motivation [ 10 , 11 ] and attentional processing [ 12 ].…”

Carbohydrate Mouth Rinsing Enhances High Intensity Time Trial Performance Following Prolonged Cycling

“…Interestingly, most data has indicated that the performance value of CHO MR is less prominent [ 12 , 13 ], and in many cases non-existent, when exercise is performed in a post-prandial/carbohydrate-fed state [ 12 , 14 , 15 , 16 , 17 ]. However, CHO MR has repeatedly been shown to elicit higher power output and faster race times in events lasting between 30 and 75 min when performed in a post-absorptive/fasted state [ 10 , 11 , 12 , 18 , 19 , 20 ], with three exceptions [ 16 , 21 , 22 ]. Though only examined on a few occasions, CHO MR does not typically benefit high-intensity/sprint performance [ 20 , 23 , 24 ].…”