Physical activity is associated with a distinct gut microbial metabolic profile in healthy adults: a pilot study with implications for musculoskeletal health
Location
LSU Health NO Center for Advanced Learning and Simulation (CALS)
Document Type
Event
Start Date
20-6-2026 10:20 AM
End Date
20-6-2026 11:20 AM
Publication Date
June 2026
Description
Introduction: The gut microbiome is increasingly recognized as a modulator of musculoskeletal health, influencing bone metabolism, skeletal muscle function, and systemic inflammation through microbially produced metabolites, including short-chain fatty acids (SCFAs). Physical activity (PA) is a cornerstone of orthopedic rehabilitation and musculoskeletal health promotion, yet its relationship to microbial metabolic output remains poorly characterized. Understanding how habitual PA shapes the gut microbiome may have implications for recovery after orthopedic surgery, management of musculoskeletal conditions, and optimization of rehabilitation outcomes.
Methods: Sixty-five healthy adults (34 females, 31 males; mean age 36.8 ± 8.4 years; mean BMI 26.6 ± 5.2 kg/m²) participated in this pilot cross-sectional study. PA was assessed with the International Physical Activity Questionnaire (IPAQ). Fecal samples were analyzed by 16S rRNA sequencing to assess microbial community composition and by GC-MS for untargeted metabolomics and SCFA composition. Gut transit time was estimated using the Bristol Stool Scale. Dietary intake was assessed via 24-hour recall using the validated ASA24. Spearman correlations were used to examine associations between PA and fecal and dietary measures. Values reported are not corrected for FDR. Mediation analysis tested whether gut transit time mediated associations between PA and fecal metabolite abundance, adjusting for age, sex, BMI, and total energy intake.
Results: Higher PA was associated with higher Bristol Stool Scale scores, indicating faster gut transit ( =0.27, p = 0.022), but was not associated with macronutrient intake, fecal water content, or fecal nitrogen. Twenty-five fecal metabolites were negatively associated with PA before FDR correction, spanning pathways directly relevant to musculoskeletal function, including butanoate metabolism, amino acid biosynthesis and catabolism, nitrogen metabolism, fatty acid biosynthesis, and NAD⁺ precursor metabolism. More active individuals showed microbial enrichment of saccharolytic SCFA-producing taxa, including Coprococcus_A ( =0.29, p = 0.04), Blautia_A ( =0.30, p = 0.03), Dorea_A ( =0.33, p = 0.02), and Ruminococcus_C ( =0.37, p = 0.007), alongside depletion of proteolytic taxa, including Bacteroides_H intestinalis ( =-0.34, p = 0.02) and Phocaeicola_A ( =-0.34, p = 0.02). Despite enrichment of butyrate-producing bacteria, fecal SCFA, including butyrate ( =-0.009, p = 0.94), propionate ( =-0.07, p = 0.64), and acetate ( =-0.2, p = 0.17), were not associated with PA. Gut transit time did not mediate associations between PA and fecal metabolite abundance.
Discussion: In this pilot study, physically active individuals harbored a gut microbial community characterized by efficient saccharolytic fermentation, reduced proteolytic activity, and a metabolic profile consistent with enhanced colonocyte absorption of microbially produced SCFAs.
Significance/Clinical relevance: These findings are relevant to orthopedic practice given the established roles of butyrate in skeletal muscle mitochondrial function and insulin sensitivity, propionate in bone metabolism and osteoblast activity, and microbial amino acid metabolism in systemic inflammation, all of which influence surgical recovery, implant integration, and rehabilitation outcomes. PA level may be an important determinant of the gut microbial environment that orthopedic patients bring to surgery, warranting further investigation in clinical populations.
Recommended Citation
Byerley, Lauri PhD, "Physical activity is associated with a distinct gut microbial metabolic profile in healthy adults: a pilot study with implications for musculoskeletal health" (2026). Dept. of Orthopaedics: Robert D. D’Ambrosia Lectureship & Research Day. 2.
https://digitalscholar.lsuhsc.edu/ortho_rd/2026/student/2
Physical activity is associated with a distinct gut microbial metabolic profile in healthy adults: a pilot study with implications for musculoskeletal health
LSU Health NO Center for Advanced Learning and Simulation (CALS)
Introduction: The gut microbiome is increasingly recognized as a modulator of musculoskeletal health, influencing bone metabolism, skeletal muscle function, and systemic inflammation through microbially produced metabolites, including short-chain fatty acids (SCFAs). Physical activity (PA) is a cornerstone of orthopedic rehabilitation and musculoskeletal health promotion, yet its relationship to microbial metabolic output remains poorly characterized. Understanding how habitual PA shapes the gut microbiome may have implications for recovery after orthopedic surgery, management of musculoskeletal conditions, and optimization of rehabilitation outcomes.
Methods: Sixty-five healthy adults (34 females, 31 males; mean age 36.8 ± 8.4 years; mean BMI 26.6 ± 5.2 kg/m²) participated in this pilot cross-sectional study. PA was assessed with the International Physical Activity Questionnaire (IPAQ). Fecal samples were analyzed by 16S rRNA sequencing to assess microbial community composition and by GC-MS for untargeted metabolomics and SCFA composition. Gut transit time was estimated using the Bristol Stool Scale. Dietary intake was assessed via 24-hour recall using the validated ASA24. Spearman correlations were used to examine associations between PA and fecal and dietary measures. Values reported are not corrected for FDR. Mediation analysis tested whether gut transit time mediated associations between PA and fecal metabolite abundance, adjusting for age, sex, BMI, and total energy intake.
Results: Higher PA was associated with higher Bristol Stool Scale scores, indicating faster gut transit ( =0.27, p = 0.022), but was not associated with macronutrient intake, fecal water content, or fecal nitrogen. Twenty-five fecal metabolites were negatively associated with PA before FDR correction, spanning pathways directly relevant to musculoskeletal function, including butanoate metabolism, amino acid biosynthesis and catabolism, nitrogen metabolism, fatty acid biosynthesis, and NAD⁺ precursor metabolism. More active individuals showed microbial enrichment of saccharolytic SCFA-producing taxa, including Coprococcus_A ( =0.29, p = 0.04), Blautia_A ( =0.30, p = 0.03), Dorea_A ( =0.33, p = 0.02), and Ruminococcus_C ( =0.37, p = 0.007), alongside depletion of proteolytic taxa, including Bacteroides_H intestinalis ( =-0.34, p = 0.02) and Phocaeicola_A ( =-0.34, p = 0.02). Despite enrichment of butyrate-producing bacteria, fecal SCFA, including butyrate ( =-0.009, p = 0.94), propionate ( =-0.07, p = 0.64), and acetate ( =-0.2, p = 0.17), were not associated with PA. Gut transit time did not mediate associations between PA and fecal metabolite abundance.
Discussion: In this pilot study, physically active individuals harbored a gut microbial community characterized by efficient saccharolytic fermentation, reduced proteolytic activity, and a metabolic profile consistent with enhanced colonocyte absorption of microbially produced SCFAs.
Significance/Clinical relevance: These findings are relevant to orthopedic practice given the established roles of butyrate in skeletal muscle mitochondrial function and insulin sensitivity, propionate in bone metabolism and osteoblast activity, and microbial amino acid metabolism in systemic inflammation, all of which influence surgical recovery, implant integration, and rehabilitation outcomes. PA level may be an important determinant of the gut microbial environment that orthopedic patients bring to surgery, warranting further investigation in clinical populations.