The Reliability of Electromyographic Normalization Methods for Cycling Analyses

Abstract

Electromyography (EMG) is normalized in relation to a reference maximum voluntary contraction (MVC) value. Different normalization techniques are available but the most reliable method for cycling movements is unknown. This study investigated the reliability of different normalization techniques for cycling analyses. Twenty-five male cyclists (age 24.13 ± 2.79 years, body height 176.22 ± 4.87 cm and body mass 67.23 ± 4.19 kg, BMI = 21.70 ± 2.60 kg·m-1) performed different normalization procedures on two occasions, within the same testing session. The rectus femoris, biceps femoris, gastrocnemius and tibialis anterior muscles were examined. Participants performed isometric normalizations (IMVC) using an isokinetic dynamometer. Five minutes of submaximal cycling (180 W) were also undertaken, allowing the mean (DMA) and peak (PDA) activation from each muscle to serve as reference values. Finally, a 10 s cycling sprint (MxDA) trial was undertaken and the highest activation from each muscle was used as the reference value. Differences between reference EMG amplitude, as a function of normalization technique and time, were examined using repeated measures ANOVAs. The test-retest reliability of each technique was also examined using linear regression, intraclass correlations and Cronbach’s alpha. The results showed that EMG amplitude differed significantly between normalization techniques for all muscles, with the IMVC and MxDA methods demonstrating the highest amplitudes. The highest levels of reliability were observed for the PDA technique for all muscles; therefore, our results support the utilization of this method for cycling analyses.

Effects of Age, Power Output, and Cadence on Energy Expenditure and Lower Limb Antagonist Muscle Coactivation During Cycling

“…We also considered using maximal voluntary isometric contractions for EMG normalization, but this method has been criticized for not being suitable for EMG normalization during cycling (Hug & Dorel, 2009). Furthermore, recent studies showed that normalizing EMG amplitudes using peak EMG values from a submaximal condition during cycling demonstrated higher reliability and sensitivity in EMG outcomes for lower extremity muscles compared to normalization using a maximal isometric voluntary contraction (Albertus-Kajee, Tucker, Derman, & Lambert, 2010;Sinclair et al, 2015). The onsets and offsets of normalized EMG activity of each muscle during cycling trials were determined using a Teager-Kaiser energy operator (TKEO), which reduces background noise and enhances signal-to-noise ratio (Solnik, Rider, Steinweg, DeVita, & Hortobagyi, 2010).…”

The Driver’s Steering Feel Assessment Using EEG and EMG signals

“…The normalization method calculates the amplitude ratio of the measured surface EMG signals to those at the MVC. All drivers were trained to perform the MVC before the tests (Sinclair et al, 2015).…”

Efeito da Doença de Parkinson na força de mordida, atividade eletromiográfica e espessura dos músculos masseter, temporal e esternocleidomastoideo

“…A normalização eletromiográfica da função muscular pelo apertamento dental em contração voluntária máxima foi um fator importante necessário para determinar a correta interpretação dos dados de comparação entre diferentes indivíduos, músculos e dias de coletas o qual minimizou as diferenças existentes, mesmo pareando sujeito a sujeito por idade, gênero, peso e altura (Botelho et al, 2011;Rabita et al, 2000;Sinclair et al, 2015;Schwartz et al, 2017 Garg, 2016;Fraiwan et al, 2016;Yakabi et al, 2017).…”