Exercise and the Gut Microbiome: From Mechanisms to Clinical Applications.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing human and animal studies without systematic meta-analysis.
PubMed 42197026 · doi:10.3390/nu18101565
What was done
Authors searched PubMed, Scopus, Web of Science, and SID from January 2000 to February 2025 for studies on exercise and the gut microbiome. From 218 identified records, 89 original studies (47 human and 42 animal) met inclusion criteria and were critically appraised in this narrative review.
What was found
The abstract reports no numerical effect sizes or pooled statistics. Moderate-intensity continuous training consistently increased alpha diversity and enriched butyrate-producing taxa (Faecalibacterium prausnitzii, Roseburia hominis) and Akkermansia muciniphila. High-intensity interval training transiently increased intestinal permeability in untrained individuals but stimulated butyrate production via lactate cross-feeding after adaptation. Effects were transient and reversed with detraining. Animal studies demonstrated causality through fecal microbiota transplantation, while human randomized trials showed modest, intensity-dependent, and highly individualized responses with no definitive evidence linking microbial shifts to athletic performance.
Why it matters
It summarizes current mechanistic and translational evidence linking physical activity to the gut microbiome and the gut-muscle axis. It clarifies that microbial shifts from exercise are transient lifestyle adaptations requiring continued training rather than permanent alterations.
Limits
The paper is a narrative review without quantitative meta-analysis, pooled effect sizes, or risk-of-bias metrics. Findings depend heavily on animal models, and cited human trials suffer from small sample sizes, lack of dietary control, short intervention durations, and significant inter-individual variability.
Cited by
- supports Exercise has been shown to increase butyrate-producing bacteria in the gut microbiome.