Creatine kinase behavior after eccentric muscle damage and its relationship with muscle viscoelastic properties in ischemic preconditioning: a randomized placebo-controlled clinical trial

• Grant number: 22/11958-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2023
• End date: January 31, 2024
• Field of knowledge: Biological Sciences - Physiology - Physiology of Effort
• Principal Investigator: Franciele Marques Vanderlei
• Grantee: Vinícius Pagani
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

Introduction: resistance training, among the strategies used to prevent injuries, stands out mainly with regard to the maintenance and improvement of strength and muscle mass. In this scenario, eccentric exercise (EE) is characterized by stretching the muscle fibers, which, during contraction, promotes greater tension, generating an increase in strength. Despite this, it is known that this type of exercise, due to the overload exerted on the musculotendinous units, causes a deformation of these structures, generating changes in the viscoelastic properties of the muscle (tone, rigidity and elasticity) and an increase in creatine kinase (CK) levels, which may result in injuries. Thus, ischemic preconditioning (IPC) can be used as a strategy to reduce muscle damage caused by EE, reducing the deleterious effects of ischemia-reperfusion, and can be used to accelerate the post-exercise recovery process. However, there is no data to evaluate the behavior of the concentration of biomarkers such as CK and its influence on muscle viscoelastic properties in response to different pressures of occlusion of IPC. Objective: to evaluate, in muscle damage induced by EE, the behavior of CK after IPC at different occlusion pressures and correlate them with muscle viscoelastic properties (muscle tone, stiffness and elasticity). Methods: a randomized placebo-controlled clinical trial will be carried out with 80 men aged between 18 and 35 years who will be randomly divided into four groups: IPC using total occlusion pressure (TOP), IPC with 40% more than TOP, placebo (10 mmHg) and control. The IPC and placebo protocol will consist of four cycles of ischemia and reperfusion of five minutes each, while the control will remain at rest in the supine position. All groups will perform an EE protocol, initial evaluations, evaluations immediately after the end of EE, 24, 48, 72 and 96 hours after exercise, being evaluated the CK through the collection of capillary blood from the digital pulp and later analyzed in the Reflotron Plus System and the viscoelastic properties of muscle tension, stiffness and elasticity through myotonometry. For statistical analysis, the descriptive statistical method, analysis of variance for repeated measures model and linear regression will be used. The significance level will be p<0.05.