Efficacy of an isometric pre-conditioning protocol on preventing the manifestation of exercise induced muscle damage following two different eccentric exercise protocols

• Grant number: 17/14632-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2018
• End date: December 31, 2018
• Field of knowledge: Health Sciences - Physical Education
• Principal Investigator: Benedito Sérgio Denadai
• Grantee: Renan Vieira Barreto
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil

Abstract

Introduction: Exercise-induced muscle damage (EIMD) occurs following unaccustomed eccentric-biased exercise. Manipulation of certain eccentric exercise variables such as load, angular velocity and range of motion modulates the magnitude of EIMD response. Pre-conditioning with maximal isometric contractions 2-4 days prior to damaging bouts has been shown to attenuate some EIMD symptoms. However, it is not currently known if the protective effect conferred by isometric pre-conditioning (IPC) is the same against different magnitudes of stress applied to the muscle. Objective: To investigate if the same PCI protocol would attenuate EIMD induced by two different maximal eccentric exercise protocols (MaxECC) in similar fashion. Methods: Healthy, untrained, males will be allocated to four different groups (n=10): CON-S, ISO-S, CON-F, ISO-F. All groups will perform MaxECC protocols with the elbow flexors at either slow (CON-S, ISO-S) or fast (CON-F, ISO-F) angular speeds and EIMD symptoms (isokinetic peak torque, muscle soreness, muscle thickness, and ultrasound echo-intensity of the elbow flexors) will be assessed before, immediately after and 1-4 days following the MaxECC. Two experimental groups (ISO-S, ISO-F) will perform a IPC protocol (10 maximal isometric contractions with 45-second rest intervals) two days prior the MaxECC. Changes over time and between groups in all EIMD symptoms will be analyzed via two-way factorial ANOVA (normal distribution) and Friedman and Kruskal-Wallis (non-parametric distribution). Indexes of protection will be calculated considering the data obtained from both MaxECC angular speeds and compared with the Mann-Whitney test. Statistical significance will be set as p < 0.05. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BARRETO, RENAN VIEIRA; RABELLO DE LIMA, LEONARDO COELHO; GRECO, CAMILA COELHO; DENADAI, BENEDITO SERGIO. Protective Effect Conferred by Isometric Preconditioning Against Slow- and Fast-Velocity Eccentric Exercise-Induced Muscle Damage. FRONTIERS IN PHYSIOLOGY, v. 10, OCT 1 2019. (17/14632-0)