Genetic Variation, Inflammatory And Muscle Injury Response In Rugby Players To Different Positions In The Field

BACKGROUND: In the rugby match the number of collisions depends on the position of the players. Muscle injury and inflammatory response is usually attributed to mechanical and metabolic injury, and recently, to genetic polymorphisms. This study aims to investigate genetic variation, muscle injury and inflammatory response induced by rugby training to the position of the athletes.METHODS: Cardiopulmonary exercise test and anthropometric parameters were performed in thirty-eight male rugby players aged between 18-32 years old and separated in forwards and backs. The muscle injury and inflammatory response were evaluated through the measurement of cytokines (IL-12, IL-10, IL-6, TNF-alpha, IL-1 beta and IL-8), C-reactive protein, heat shock protein 70, creatine kinase (CK) and lactate dehydrogenase (LDH) before and after a training session. Angiotensin converting enzyme (ACE) I/D and alpha-actinin-3 (ACTN-3) R577X, angiotensinogen Met235Thr and bradykinin receptor B2-9/+9 polymorphisms were performed.RESULTS: Forwards group showed higher values body mass index (BMI), body mass, fat percentage, lean and fat mass, ACTN-3 RX genotype frequency, anaerobic threshold speed and respiratory compensation point speed when compared to the backs. In forwards, the match induced an increase on CK and LDH activities, IL-10, IL-6 and IL-8 levels, while in the backs the training just elevated LDH and IL-8 levels.CONCLUSIONS: We concluded that forwards have pronounced muscle damage and inflammatory response than backs, highlighting the importance of the position in the field to determine a personalized training and recovery.