Author Identifier
B. Charlesson: https://orcid.org/0009-0005-0040-4835
C. Abbiss: https://orcid.org/0000-0003-3940-5542
C. T. Christophersen: https://orcid.org/0000-0003-1591-5871
Document Type
Journal Article
Publication Title
Journal of the International Society of Sports Nutrition
Volume
22
Issue
1
Publisher
Taylor & Francis
School
School of Medical and Health Sciences
Funders
Edith Cowan University
Abstract
Background: Despite the importance of the gut microbiome on physical performance and health, little is known on the impact of training on an athlete’s gut health. Objective: This study investigates the effect of training load on markers of gut health. Methods: Whole stool (24 h) samples were collected from 23 highly trained rowers (mean ± SD; age 19.2 ± 1.1 y; weight 80.1 ± 11.4 kg; height 1.83 ± 0.09 m) following periods of high (HT) and low training load (LT). The microbiome and short-chain fatty acid concentrations were characterized from the whole stool samples. Three-day weighted food records were used to determine diet quality (ADIcore), macronutrient, and fiber intakes during HT and LT. Results: By design, training duration (147%) and intensity (130%) were greater during (HT), compared with (LT) (p < 0.001). Carbohydrate, fat, protein, and fiber intake remained stable, but ADIcore was higher in HT (55 ± 10) compared with LT (49 ± 9; t(15) = 2.78, p = 0.014; CI: 1.34 to 10.155). Stool frequency (1.11 ± 0.47 vs 0.67 ± 0.76; p = 0.007) was lower in HT compared with LT, and a greater number of participants were unable to produce a stool sample during LT (8% vs 47%). Short chain fatty acid (SCFA), propionic (120.64 ± 30.06 mm vs 91.35 ± 34.91 mm; p = 0.007), and butyric acid (104.76 ± 50.02 vs 64.23 ± 22.05 mm, p = 0.003) concentrations were lower in HT compared with LT. Alpha diversity, Shannon–Wiener diversity index (3.43 ± 0.37 vs 3.67 ± 0.34, p = 0.09) was lower in HT than LT. The abundance of the dominant Bacteroidia was greater at HT compared to LT and ratio of firmicutes to Bacteroidota (n = 16, 1.31 ± 1.19 vs 4.29 ± 3.88, t(15) = -3.44, p = 0.04, CI = -4.82 to −1.13) was lower in HT compared to LT. Conclusion: Results of this study indicate that gut microbiome, SCFA concentrations, stool frequency, and diet quality vary between periods of high and low training load in athletes. The relationship between these factors and impact of such changes in gut health is currently unclear and warrants further investigation.
DOI
10.1080/15502783.2025.2507952
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Charlesson, B., Jones, J., Abbiss, C., Peeling, P., Watts, S., & Christophersen, C. T. (2025). Training load influences gut microbiome of highly trained rowing athletes. Journal of the International Society of Sports Nutrition, 22(1), 2507952. https://doi.org/10.1080/15502783.2025.2507952