Effects of low level laser therapy in peripheral muscle fatigue in elderly women submitted to a program of quadriceps femoris strength training

• Grant number: 12/12472-1
• Support Opportunities: Regular Research Grants
• Duration: May 01, 2013 - October 31, 2015
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Helga Tatiana Tucci
• Grantee: Helga Tatiana Tucci
• Host Institution: Pró-Reitoria de Pós-Graduação e Pesquisa. Universidade Federal de São Paulo (UNIFESP). São Paulo , SP, Brazil
• Associated researchers: Ana Claudia Muniz Renno ; Carlos Eduardo Pinfildi ; Mariana Chaves Aveiro ; Renata Luri Toma

Abstract

Among many changes associated with aging that lead to the decline of muscle function can be cited the sarcopenia. Within this context, the muscle strength may be important in the prevention and in recovering of some of these muscle disorders. However, muscle performance during a physical training can be reduced by early muscle fatigue. The laser, by its biomodulation effects, may be a resource for reducing muscle fatigue and increasing the effectiveness of training. The objective of this study is to analyze the influence of low level laser therapy (LLLT) in the quadriceps femoris performance of elderly women before and after a strength training program and in the load values used in this training. For this, 45 elderly women will be randomly divided into 3 groups: strength training (n = 26) associated with sham laser irradiation, group strength training associated with the active laser irradiation (n = 26) and control group (n = 26) did not submitted to training and laser therapy. The analysis of peripheral muscle fatigue will be performed by surface electromyography, inflammatory markers and blood lactate concentration. Quadriceps femoris strength training will last eight weeks and it will be performed in a leg extension chair following the recommendations of the American College of Sports Medicine. The LLLT will be held immediately after each training session over rectus femoris, vastus lateralis and vastus medialis muscles of the dominant leg. Before first, after last training session and 24 hours after, electromyographic activity and blood samples collection will be made after quadriceps femoris fatigue protocol. The fatigue protocol consists of performing a isometric submaximal contraction, performed until muscle exhaustion, with 80% of total force obtained during a muscular isometric contraction. Eletromyographic raw signal will be used to derive the median frequency (FMed), mathematical calculation used to analyze electromyographic fatigue. Normalized FMed, blood lactate concentration, and inflammatory markers will be compared inter and intra-groups, as well as progression of load values during training will be compared between groups. The normality in terms of sample distribution will be investigated for choosing appropriate statistical tests. (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)

TUCCI, HELGA TATIANA; FIGUEIREDO, DANIELLE S.; CARVALHO, RAQUEL DE PAULA; SOUZA, ANA C. F.; VASSAO, PATRICIA G.; RENNO, ANA C. M.; CIOL, MARCIA A.. Quadriceps femoris performance after resistance training with and without photobiomodulation in elderly women: a randomized clinical trial. Lasers in Medical Science, v. 34, n. 8, p. 1583-1594, OCT 2019. (12/12472-1)