Within- and between-day reliability and repeatability of neuromuscular function assessment in females and males

Author(s)

Dutra, Yago Medeiros ; Lopes, Joao Pedro Fialho ; Murias, Juan M. ; Zagatto, Alessandro Moura

• Document type: Journal article
• Source: Journal of Applied Physiology; v. 135, n. 6, p. 12-pg., 2023-12-02.

Abstract

The study evaluated the reliability and repeatability of the force and surface electromyography activity (EMG) outcomes obtained through voluntary and electrically evoked contractions of knee extensors in females (n = 18) and males (n = 20) and compared these data between sexes. Maximal isometric voluntary contractions (iMVCs) of knee extensors associated with electrical stimulation of the femoral nerve were performed over 4 days (48-h interval), with the first day involving familiarization procedures, the second involving three trials (1-h interval), and the third and fourth involving just one trial. The intraclass correlation coefficient (ICC), coefficient of variation (CV), and repeatability of outcomes from within- and between-day trials were determined for each sex. Females presented lower maximal voluntary force during iMVC (iMVC(Force)) and associated vastus lateralis EMG activity (root mean square, RMSVL), force evoked by potentiated doublet high-frequency (Db(100Force)) and single stimuli (Q(tw)), and M-wave amplitude than males (P <= 0.01, partial eta squared >= 0.94). Voluntary activation (VA) and RMSVL/M-wave amplitude did not differ between sexes. iMVC(Force), VA, Db(100Force), Q(tw), and M-wave amplitude were the most reliable outcomes in within-day trials, with similar results between sexes (ICC > 0.62; CV < 6.4%; repeatability: 12.2%-22.6%). When investigating between-day trials, the iMVC(Force), VA, Db(100Force), and Q(tw) were the most reliable (ICC > 0.66; CV < 7.5%; repeatability: 13.2%-33.45%) with similar results between sexes. In conclusion, females presented lower iMVC(Force) and evoked response than males. Although reliability and repeatability statistics vary between trials, data (e.g., from EMG or force signal), and sexes, most of the outcomes obtained through this technique are reliable in females and males. (AU)

• FAPESP's process: 21/08479-0 - Time course of neuromuscular recovery after running training session: influence of intensity, hot water immersion and cold water immersion
• Grantee: Yago Medeiros Dutra
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 22/01173-5 - Time course of neuromuscular fatigue after exercise in the heat: are heart rate variability and blood markers sensitive?
• Grantee: João Pedro Fialho Lopes
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 21/14156-9 - Influence of exercise protocol and metabolic instability on oxygen uptake slow component and oxygen uptake functional gain during constant-work rate effort within the heavy and severe intensity domains in cycling
• Grantee: Alessandro Moura Zagatto
• Support Opportunities: Scholarships abroad - Research