BACKGROUND/OBJECTIVES: Substance use disorders (SUDs) present a global health challenge with high relapse rates. Emerging evidence implicates gut microbiota dysbiosis in SUD pathophysiology via the gut-brain axis. This 24-week randomized controlled trial investigated whether precision exercise interventions could modulate the gut microbiota-emotion axis to improve psychological outcomes in individuals undergoing compulsory drug rehabilitation.
METHODS: Thirty male participants were randomized to a precision exercise group (n = 15; individualized aerobic + resistance training, 4-5 sessions/week) or control group (n = 15; standard rehabilitation activities). Multi-dimensional assessments included weekly fecal (16S rRNA sequencing), urine (SCFAs via GC-MS), and saliva samples (cortisol, serotonin, BDNF via ELISA), alongside psychological evaluations (SCL-90-R, POMS) and physiological measures.
RESULTS: The exercise group exhibited significant increases in gut microbial diversity (Shannon index: +18.2%, p < 0.001; Cohen's d = 2.14) and enrichment of beneficial taxa (e.g., Faecalibacterium, Bifidobacterium; LDA >3.5). Urinary SCFAs increased markedly (butyrate: 3.12-fold, p < 0.001), correlating with elevated salivary BDNF (+82%, p < 0.001) and reduced cortisol (-41.1%, p < 0.001). Psychological outcomes improved substantially: SCL-90-R Global Severity Index decreased by 43.3% (p < 0.001), and 78.6% of exercise participants achieved clinically meaningful improvement. Machine learning models predicted treatment response (AUC = 0.91) using baseline microbiome features.
CONCLUSIONS: Precision exercise restores gut microbiota homeostasis, enhances neuroactive metabolite production, and improves emotional regulation in SUD recovery. The gut microbiota-emotion axis represents a viable target for non-pharmacological interventions, with microbiome profiles enabling personalized treatment strategies.
Gut-Brain Axis