A linear regression between maximum voluntary contraction and motor unit activity of respiratory muscles during forceful and normal respiration of male athletes using surface electromyography

Abstract

The primary objective of this study is to establish a relationship between maximum voluntary contraction (MVC) and motor unit activity (RMS) during forced and normal respiration.Fifty-nine male athletes between the ages of 15-20 years participated.During forceful and regular respiration surface electromyography (sEMG) was performed on participants' external intercostal, diaphragm, and latissimus dorsi muscles.The raw sEMG recordings were filtered to compute MVC and RMS.Pearson's correlation test revealed a substantial positive association between MVC and RMS for all muscles (p<0.05).A simple linear regression model was used to establish the best feasible equation based on correlation.MVC shows interconnection with RMS during both respiration in both groups, indicating variations in motor unit activity during respiration may contribute to a muscle's maximum ability to generate force.In these situations, 'y=b+mx' can be used to quantitatively express the link between MVC and RMS.