The Muscle Mag
The researchers from Spain enlisted 16 professional cyclists participating in the Vuelta a España, a 3,290.7 km Grand Tour cycling stage race that occurred in Spain, Andorra, and France from Aug. 24 to Sept. 15, 2019.
After evaluating dietary intake and fecal samples over the three-week race, the study concluded that changes in gut microbiota composition, influenced by carbohydrate (CHO) consumption, were negatively associated with performance.
“The composition and timing of supplementation during a Grand Tour, specifically carbohydrates, could be planned to adjust gut microbiota composition for better performance,” stated the researchers in the journal Nutrients.
“Future strategies to enhance the performance of elite athletes could involve promoting specific targeted bacterial taxa growth using à la carte prebiotics instead of the traditional ineffective probiotic supplementation, which typically fails to sustain stable populations in the gut ecosystem.”
Athletes’ gut health
Grand tours consist of consecutive and continuous days of intense competition, entailing extreme physiological and metabolic demands and responses, factors of exercise that have been recognized as influences that can alter the diversity and abundance of certain bacterial groups.
Research indicates that gut microbiota composition and metabolic activity significantly impact physical performance, with a growing interest in the potential of sports supplements to improve performance by adjusting gut microbiota composition and metabolic activity.
Depletion of energy is a common limiting factor during exercise, frequently addressed through carb loading, where athletes increase their glycogen stores before endurance events by upping CHO intake from both food and supplements. However, evidence suggests that simple CHO intake could negatively affect gut microbiota and consequently sports performance.
The effects of various supplements (probiotics, prebiotics, proteins, antioxidants, branched-chain amino acids, caffeine, etc.) on gut microbiota are well known, but the researchers highlighted the necessity for more information on how exercise, especially in high-level athletes during competition, impacts gut microbiota composition, making supplementation “inexact and possibly ineffective.”
Supplementing during races
Throughout the race, fecal samples were taken at four time points: before the first stage (A); after 9 stages (B); after 15 stages (C); and on the final stage (D). Faecal microbiota populations and SCFA content were studied using 16S rRNA sequencing and gas chromatography, correspondingly, with dietary intake recorded via a validated food frequency questionnaire.
The consumption of high-CHO sports supplements significantly increased during competition (CHO drinks: 442 ± 677%; gels: 533 ± 47%; energy bars: 288 ± 214%; sport snacks: 167 ± 145%).
The athletes also took probiotic supplements daily during the competition, including combinations of the species Bifidobacterium lactis, Bifodobacterium bifidum, Lactobacillus paracasei, and Lactobacillus acidophilus.
Data analysis was conducted to explore the dynamics of microbiota and SCFAs and their correlation with performance.
The findings revealed that Bifidobacteriaceae, Coriobacteriaceae, Erysipelotrichaceae, and Sutterellaceae presence was connected to strong final performance.
Cyclists with a lower frequency of consumption of CHO-rich supplements (CHO drinks, gels, and sports snacks combined) exhibited a tendency towards higher relative abundance of the family Bifidobacteriaceae.
While the consumption of high-CHO sports supplements substantially increased in all participants during competition, cyclists with a lower increase in their CHO consumption showed a propensity towards a higher abundance of Bifidobacteriaceae, which correlated with a lower accumulated time at the end of La Vuelta and hence, better performance.
Furthermore, the researchers found that they did not detect any of the strains included in the probiotic supplements or in the probiotic foods used.
“Though the cyclists were utilizing probiotic supplements containing bifidobacteria during competition, the relationship between bifidobacteria abundance and performance seems to be influenced by diet in a manner that is seemingly more crucial to performance than the use of probiotic supplements,” they concluded.
“Further research into the composition of the intestinal microbiota and the byproducts of its metabolic activity will aid in understanding its potential regulatory role in response to exercise and in optimizing and personalizing supplement use.”
Industry perspectives
“The outcome of the study is a significant discovery as it illustrates a direct association between shifts in the microbiome and athletes’ performance,” remarked Nathan Gray, co-founder of microbiome supplement startup Advanced Biotics.
Continuing to delve into the complex relationship between diet, the microbiome, and physical performance will make it easier to provide athletes with customized solutions that bolster their gut health and, subsequently, their athletic accomplishments, he noted.
“The connection between the microbiome and physical performance is intriguing and just beginning to be explored. This study marks one of the initial steps into this captivating unknown and could ultimately offer athletes another aspect to optimize,” added Nathan Price, chief scientific officer at Thorne HealthTech, the wellness company specializing in personalized solutions.
Journal: Nutrients
doi: 10.3390/nu16050661
“Dynamics of Gut Microbiota and Short-Chain Fatty Acids during a Cycling Grand Tour Are Related to Exercise Performance and Modulated by Dietary Intake.”
Authors: Manuela Fernandez-Sanjurjo et al.
