Optimizing normalization methods of the external oblique: A cross-sectional study
Article type: Research Article
Authors: Devorski, Luka; b | Skibski, Andrewa; b | Fukuda, David H.b; c | Stout, Jeffrey R.a; b | Ingersoll, Christopher D.b | Mangum, L. Colbya; b; *
Affiliations: [a] Rehabilitation, Athletic Assessment & Dynamic Imaging (READY) Laboratory, Institute of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, USA | [b] College of Health Professions and Sciences, University of Central Florida, Orlando, FL, USA | [c] Physiology of Work & Exercise Response (POWER) Laboratory, Institute of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, USA
Correspondence: [*] Corresponding author: L. Colby Mangum, Institute of Exercise Physiology and Rehabilitation Science, University of Central Florida, 4364 Scorpius St, Health Sciences Bldg II Room 235, Orlando, FL 32816-2205, USA. E-mail: lauren.mangum@ucf.edu.
Abstract: BACKGROUND: Adequate normalization methodology to establish maximum voluntary isometric contraction (MVIC) is needed to compare %MVIC values for core exercise completed until discontinuation. Clinicians can use %MVIC classifications to guide their preventative and rehabilitative exercise interventions. OBJECTIVE: The aim of this study was to compare %MVIC of the external oblique (EO) between normalization techniques of side-lying lateral trunk flexion and Roman chair lateral trunk flexion. METHODS: Twenty-two participants completed two MVIC techniques followed by one repetition of the prone bridge plank (PBP), torso elevated side plank (TESP), foot elevated side plank (FESP), dead bug and bird dog. The average %MVIC during the first 5-seconds, last 5-seconds and overall duration of exercise were included for analysis. ANOVA was used to compare normalized %MVIC from each of the 5 exercises between MVIC techniques. Alpha set a priori p= 0.05. RESULTS: The side-lying table technique yielded no %MVIC values above 100%, while the Roman chair technique produced 7 values above 100%. The largest mean difference between techniques was during the last 5-seconds of the torso elevated side plank (57.87 ± 38.51%MVIC, p< 0.001). CONCLUSION: The side-lying table technique likely provides the optimal methodology of %MVIC determination.
Keywords: Core stability, isometric contraction, surface electromyography
DOI: 10.3233/BMR-220368
Journal: Journal of Back and Musculoskeletal Rehabilitation, vol. 36, no. 5, pp. 1179-1184, 2023
External oblique muscle activation during exercise can be normalized to a maximum contraction.
What is it about?
Normalization methods including side-lying lateral trunk flexion have been previously used to establish the external oblique's maximum isometric contraction. The roman chair lateral trunk flexion has been proposed as an alternative normalization method. This paper compares the two normalization methods and their use during core exercise.
Why is it important?
Our findings show the side-lying trunk flexion method produced no values above 100% MVIC while the roman chair method produced 7 values above 100% MVIC. The last 5 seconds of the torso elevated side plank resulted in a 57% higher average %MVIC with roman chair normalization compared to the side-lying method. The side-lying table technique likely provides the optimal methodology of external oblique %MVIC determination.