Authors: Li Peiyao, Sun Shuo, Zhang Wenjie, Ouyang Wen, Li Xiaobin, Yang Kailun
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary: L-Citrulline Supplementation in Racing Horses Pre-exercise L-citrulline supplementation appears to enhance athletic performance in Yili speed-racing horses competing at high intensity, with researchers investigating whether this non-essential amino acid influences metabolic and physiological responses to 2000 m racing efforts. Supplemented horses received L-citrulline over 38 days, with blood analysis conducted at specific intervals to measure amino acid profiles, polyamines, blood gases, antioxidant markers, and nitric oxide concentrations before and after competitive racing. Key findings revealed significantly elevated plasma citrulline and arginine in the supplemented group alongside improved lactate clearance immediately post-race and faster recovery of blood gas parameters; additionally, antioxidant enzymes (superoxide dismutase and catalase) increased substantially whilst oxidative damage markers (malondialdehyde) decreased. For equine practitioners, these results suggest L-citrulline may offer tangible benefits for sport horse conditioning programmes by reducing metabolic fatigue accumulation and enhancing cellular oxidative protection—particularly relevant for high-intensity racing disciplines where lactate management and recovery speed directly impact performance and welfare. Further investigation across different horse populations and exercise intensities would strengthen recommendations for supplementation protocols in racing and competition settings.
Read the full abstract on PubMed
Practical Takeaways
- •L-citrulline supplementation may enhance racing performance and post-exercise recovery in sport horses by reducing lactate accumulation and improving blood gas normalization
- •The supplement appears to strengthen antioxidant defenses during high-intensity exercise, potentially reducing exercise-induced cellular damage in athletic horses
- •Consider L-citrulline as a performance-enhancing nutritional strategy for competition horses, though optimal dosing, timing, and long-term safety require further investigation
Key Findings
- •L-citrulline supplementation significantly increased plasma citrulline and arginine concentrations while decreasing alanine, serine, and threonine
- •L-citrulline group showed significantly reduced immediate post-race lactate levels and accelerated blood gas recovery after 2000 m racing
- •Total antioxidant capacity increased significantly and malondialdehyde decreased in the L-citrulline group, with elevated superoxide dismutase and catalase levels
- •Polyamine concentrations (putrescine and spermidine) were significantly increased in the L-citrulline supplemented horses