<i>Clostridium butyricum</i> GKB7 increase Physical Performance and Improve Biochemistry Profile on Mice with Inherently Low Aerobic Capacity

<b>Introduction:</b> This study investigates the effects of <i>Clostridium butyricum</i> GKB7 (CB), a product manufactured by Grape King Bio Ltd., on enhancing exercise performance and blood biochemistry in mice with intrinsically low aerobic exercise capacity. <b>Methods:</b> Using a low aerobic exercise capacity mouse model (n = 48), animals were divided into six groups (n = 8 per group) based on body weight balancing principles: Control group (Vehicle), Positive control group (BCAA), Low-dose CB group (CB-L; 0.01 g human equivalent dose), High-dose CB group (CB-H; 0.1 g human equivalent dose), Low-dose heat-killed CB group (HK-CB-L; 0.01 g human equivalent dose), and High-dose heat-killed CB group (HK-CB-H; 0.1 g human equivalent dose). After four weeks of continuous supplementation, aerobic endurance and balance-related tests were performed, including weight-loaded swimming to exhaustion, treadmill running to exhaustion, and rotarod running, along with oral glucose tolerance test (OGTT) assessments. The experimental protocol involved daily supplementation of CB in different dosages, followed by endurance performance assessments and biochemical analyses. <b>Results:</b> We evaluated the effects of four-week supplementation with live or heat-killed <i>Clostridium butyricum</i> GKB7 (CB; low/high dose) on performance and energy stores in mice with low innate exercise capacity. Both live and heat-killed CB improved aerobic endurance versus vehicle: weight-loaded swimming time increased 1.49-1.87-fold, and treadmill running time increased 1.16-1.22-fold (all <i>p</i><0.05 vs vehicle; BCAA: 1.09-fold vs vehicle; no significant CB-BCAA differences on treadmill). Neuromotor performance also improved: maximum and average balance times increased 1.49-2.13-fold and 1.61-2.29-fold versus vehicle (<i>p</i><0.05); heat-killed CB groups were higher than BCAA on balance (≈1.20-1.43-fold for maximum; 1.24-1.47-fold for average). CB elevated energy reserves versus vehicle, with hepatic glycogen increased 2.55-2.74-fold and skeletal muscle glycogen increased 1.18-1.24-fold (<i>p</i><0.05). Additionally, both live and heat-killed CB increased gut microbiota diversity and enriched symbiotic beneficial taxa. Alpha diversity increased in HK-CB-L vs. CB-L/CB-H and BCAA (<i>p</i><0.05); F/B ratio was lower in CB-L and CB-H vs. their heat-killed counterparts (<i>p</i><0.05). LEfSe identified taxa enriched toward dominant/symbiotic beneficial bacteria. Collectively, CB-viable or heat-killed-enhances aerobic endurance, balance performance, and glycogen storage, with heat-killed CB showing advantages over BCAA on balance. <b>Conclusions:</b> Four-week supplementation of <i>C. butyricum</i> GKB7, significantly enhanced gut microbiota diversity and symbiotic bacterial proportions in mice with naturally low exercise capacity. Moreover, supplementation significantly improved aerobic endurance, balance performance, and glycogen storage, demonstrating its potential as an ergogenic aid.