Immune-modulating effects of regular aerobic exercise in gastrointestinal disorders: Inflammatory markers and heart rate variability

This study investigates the effects of a 12-week moderate-intensity aerobic exercise intervention on autonomic function, inflammatory markers, and symptom severity in those with gastrointestinal (GI) disorders, specifically inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), compared to apparently health controls (AHC). Heart rate variability (HRV) parameters, specifically low frequency, significant increased within the GI and AHC cohort post-intervention; additional increased parasympathetic parameters were observed in AHC. No significant reductions occurred in the inflammatory markers of CRP, TNF, or IL-17; although, a greater reduction in TNF concentration among AHC group resulted in a significant between-group difference post-intervention. Significant correlations indicated a negative correlation between TNF and parasympathetic HRV measures post-intervention. Twelve-weeks moderate-intensity aerobic exercise is effective to modulate autonomic function, particularly the autonomic balance, and provide a slight reduction in inflammatory cytokines among patients with GI disorders. The blunted vagal tone and dysregulated immunological-inflammatory profiles are speculated to hinder the physiological changes in IBD and IBS; although further research is required to support or refute this concept. This study supports use of exercise as a complementary intervention to maintain health, well-being, and physical fitness, without disease exacerbation or adverse effects of medication.