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Peart, Daniel J.
– Review the existing literature investigating carbohydrate mouth rinsing (CMR) as an ergogenic aid by using the effect sizes and percentage change in performance of the respective studies as outcome measures.
1. A trivial-small average overall effect size was present for the 25 studies included in the review
2. Effect sizes for the sub-groups were; >=25-min (0.25), <= 180 seconds (0.06), resistance exercise (-0.09) but the effect size is still small.
3. A sub-analysis of ~1-h cycling time trial performance resulted in an overall effect size of 0.20, and effect sizes for performance time and power output of 0.31 and 0.19 respectively
– Whilst effect sizes were small the average percentage change in performance in ~1-h trials was 2.48%, which may have implications for elite performers as this is greater than the 1.30% smallest worthwhile change recommended in past research.
Devenney S, et al.
– Identify the effects of mouth rinsing with a 6% and 16% carbohydrate solution (CHO) on time trial performance when compared to a 0% control (PLA) when in a fed state.
– 12 recreationally active males underwent three trials by which they had to complete a set workload (600 ± 65 W) in a fed state.
– Throughout each trial, participants rinsed their mouths with a 25 ml bolus of
(1) 0% PLA
(2) 6% CHO (maltodextrin) for every 12.5% of work completed.
(3) 16% CHO (maltodextrin) for every 12.5% of work completed.
– Rating of perceived exertion (RPE) and heart rate were recorded every 12.5% of total work.
(1) Performance times and power output improved significantly when using the 6% and 16% CHO versus the PLA trial
(2) When comparing the performance times of the 6% to 16% CHO, no significance was observed
(3) There was no significant difference between heart rate levels or RPE values across the three trials.
– mouth rinsing with a 6% or 16% CHO solution has a positive effect on a cycling time trial performance undertaken in a fed state.
Ian Rollo1, Vicky L. Goosey-Tolfrey
– Investigated the influence of mouth rinsing a carbohydrate solution on self-selected intermittent variable speed running performance.
(1) 11 male soccer players completed a modified version of the Loughborough Intermittent Shuttle Test (LIST) on two occasions separated by 1 week.
(2) The modified LIST allowed the self-selection of running speeds during block 6 of the protocol (75-90 min).
(3) Players rinsed and expectorated
– 25 ml of non-caloric placebo (PLA)
– or 10% maltodextrin solution (CHO) for 10 s, routinely during block 6 of the LIST.
(4) Self-selected speeds during the walk and cruise phases of the LIST were similar between trials.
(1) Jogging speed was significantly faster during the CHO (11.3 ± 0.7 km·h-1) than during the PLA trial (10.5 ± 1.3 km · h-1)
(2) 15 m sprint speeds were not different between trials (PLA: 2.69 s ± 0.18 s: CHO: 2.65 s ± 0.13 s) (F (2, 10), but significant benefits were observed for sprint distance covered
(3) The threshold for the smallest worthwhile change in sprint performance was set at 0.2 s. Inferential statistical analysis showed the chance that CHO mouth rinse was beneficial, negligible or detrimental to repeated sprint performance was 86%, 10% and 4% respectively
(1) Mouth rinsing and expectorating a 10% maltodextrin solution was associated with a significant increase in self-selected jogging speed
(2) Repeated 15 m sprint performance was 86% likely to benefit from routine mouth rinsing a CHO solution in comparison to a taste matched placebo
Gam S1, Guelfi KJ, Fournier PA.
(1) There is evidence carbohydrate (CHO) mouth rinsing can improve endurance exercise performance as well as muscle force production and sprint performance
(2) Whether the oral administration of non-CHO tastants also affects exercise performance is not known
(3) The purpose was to investigate whether mouth rinsing and ingesting a bitter-tasting solution of quinine improves maximal sprint cycling performance
– 14 competitive male cyclists performed a 30-s maximal cycling sprint immediately after
(1) rinsing their mouth for 10 s and then ingesting a 2-mM bitter quinine solution
(2) plain water
(3) a 0.05% (w/v) sweet aspartame solution
(4) no solution at all (control)
– Cycling power output was recorded during the sprint.
– Heart rate, perceived exertion, blood lactate, and blood glucose were measured preexercise, immediately postexercise, and 7 min postexercise
(1) Quinine significantly improved mean power output by 2.4%-3.9% compared with the three other conditions
(2) Peak power output in the quinine condition was higher compared with water (3.7%) and control (3.5%) but not significantly different from aspartame (1.9%)
(3) There were no significant differences in cycling performance between water, aspartame, and control conditions
(4) There were no differences in heart rate, perceived exertion, or blood variables between any of the conditions
– Mouth rinsing and ingesting a bitter-tasting solution immediately before a maximal sprint exercise can improve performance
Carter JM1, Jeukendrup AE, Jones DA.
PURPOSE AND METHOD:
– To investigate the possible role of carbohydrate (CHO) receptors in the mouth in influencing exercise performance.
(1) 7 male and 2 female endurance cyclists (VO(2max) 63.2 +/- 2.7 (mean +/- SE) mL.kg*(-1).min(-1)) completed two performance trials in which they had to accomplish a set amount of work as quickly as possible (914 +/- 40 kJ).
(2) On one occasion a 6.4% maltodextrin solution (CHO) was rinsed around the mouth for every 12.5% of the trial completed.
(3) On the other occasion, water (PLA) was rinsed.
(4) Subjects were not allowed to swallow either the CHO solution or water, and each mouthful was spat out after a 5-s rinse.
(1) Performance time was significantly improved with CHO compared with PLA (59.57 +/- 1.50 min vs 61.37 +/- 1.56 min, respectively).
(2) This improvement resulted in significantly higher average power output during CHO compared with PLA trial (259 +/- 16 W and 252 +/- 16 W, respectively)
(3) There were no differences in heart rate or rating of perceived exertion (RPE) between the two trials
(1) The results demonstrate that carbohydrate mouth rinse has a positive effect on 1-h time trial performance.
(2) The mechanism responsible for the improvement in high-intensity exercise performance with exogenous carbohydrate appears to involve an increase in central drive or motivation rather than having any metabolic cause.
(3) The nature and role of putative CHO receptors in the mouth warrants further investigation