Efeitos da estimulação transcraniana por corrente contínua (ETCC) na dor muscular tardia após treino resistido: protocolo para um ensaio controlado randomizado

Abstract

Backgroud: Delayed onset muscle soreness (DOMS) is a discomfort described as fatigue, pain and allodynia in the skeletal muscles after exercise. To minimize DOMS it is suggested nondrug therapies such as massage and cryotherapy. A new approach, Transcranial Direct Current Stimulation (tDCS) applied over the primary motor cortex (M1) is the focus of this study. This technique modulates the functional connectivity of sensory networks by modifying the perception of pain. Objective: To develop a protocol of a randomized controlled trial to evaluate the effects of tDCS on DOMS in 24, 48 and 72 hours after a protocol of muscle damage induced by resistance exercise. Methods: The study describes a randomized, controlled, double-blind two-arm trial protocol following the recommendations of SPIRIT/ 2013. The study will have 6 stages: initial assessment, application of five consecutive sessions of tDCS blindly, then a protocol for induction of late onset muscle pain and evaluation of pain and function soon after application of the protocol; function with 24 and 48 and 72 hours after the DMIT induction protocol. Muscle pain, assessed by Visual Analogue Scale (VAS), will be the primary outcome of the study. The secondary outcomes evaluated will be the elbow joint amplitude for flexion and extension, muscle performance and muscle power, evaluated by the dynamometry. The effects of stimulation shall be calculated using a model of analysis of variance (ANOVA). Expected results: We suggest that the presented protocol will be valid to assess whether tDCS will decrease the DMIT and improve the functionality of the active group. This protocol could be applied in further studies with a clinical population, aiming to reduce the negative effects arising from strength exercise, such as fatigue and pain.