Gut Microbiota Composition Is Related to Cardiorespiratory Fitness in Healthy Young Adults

Bacteria residing in the human gastrointestinal (GI) tract has a symbiotic relationship with its host. Animal models have demonstrated a relationship between exercise and gut microbiota composition. This was the first study to explore the relationship between cardiorespiratory fitness (maximal oxygen consumption, VO2max) and relative gut microbiota composition [Firmicutes to Bacteroidetes ratio (F/B)] in healthy young adults in a free-living environment. Twenty males and 18 females (25.7±2.2 y), who did not take antibiotics in the last 6 months, volunteered for this study. VO2max was measured using a symptom-limited graded treadmill test. Relative microbiota composition was determined by analyzing DNA extracted from stool samples using Quantitative Polymerase Chain Reaction (qPCR) that specifically measured the quantity of a target gene (16s RNA) found in Firmicutes and Bacteroidetes. Relationships between F/B and potentially related dietary, anthropometric, and fitness variables were assessed using corre...