Influence of power and wavelength on photobiomodulation therapy for muscle performance in healthy subjects

• Grant number: 21/03183-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2021
• End date: September 30, 2022
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Rinaldo Roberto de Jesus Guirro
• Grantee: Luis Carlos Caseiro Filho
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

In the last few years, photobiomodulation has been studied as a means to increase muscle performance in athletes and healthy individuals. This is possible due to the physiological changes that photobiomodulation therapy can promote. Moreover, given a large number of existing studies on the subject, some directions for future research have been established, such as the relationship between power and time. With high power, it will achieve the same energy with shorter application times. However, irradiation may not be offered for the minimum recommended time. Therefore, this study aims to compare different powers and, consequently, different application times for muscle performance in healthy individuals. For this, 42 male participants will be recruited, between 18 and 40 years old, without recent musculoskeletal injury or cardiorespiratory compromises. The participants will participate in 3 evaluations containing functional and physiological variables and ten lower limb training sessions with previous photobiomodulation therapy applications, comparing 1.08W and 1.2W power devices, with density power of 2.25 and 60 mW/cm², respectively. The lower limbs training will be composed of stiff and squat exercises twice a week, for five weeks. In the pre- and post-intervention evaluations, the isokinetic apparatus parameters, body composition, and vertical jump functionality will be evaluated. For data analysis, normality tests will be used to verify distribution and statistical tests for intra and inter-group comparisons, considering two factors: time and group. A significance level of 5% will be adopted. (AU)