Body Mass Normalization for Isometric Tests of Muscle Endurance

• Published in: Journal of strength and conditioning research 2013-07, Vol.27 (7), p.2039-2045
• Main Authors: Nuzzo, James L, Mayer, John M
• Format: Article
• Language: English
• Subjects: Adult; Athletes; Body Mass Index; Correlation analysis; Exercise Test; Firefighters; Humans; Male; Muscle, Skeletal - physiology; Muscular system; Physical Endurance - physiology; Surveys and Questionnaires
• ISSN: 1064-8011; 1533-4287
• DOI: 10.1519/JSC.0b013e3182736203

ABSTRACTNuzzo, JL and Mayer, JM. Body mass normalization for isometric tests of muscle endurance. J Strength Cond Res 27(7)2039–2045, 2013—The primary purpose of this study was to derive allometric parameters for normalizing Biering-Sorensen and Plank Test scores (measures of isometric back and abdominal muscle endurance, respectively) to body mass. The secondary purpose was to determine if allometric scaling with derived allometric parameters or the theoretical allometric parameter (b = −0.33) is the more appropriate method for normalizing Biering-Sorensen and Plank Test scores to body mass. A sample of 83 male career firefighters (age = 35.7 ± 9.4 years; body mass = 89.5 ± 14.8 kg) participated in this study. Significant correlations were found between body mass and test scores (Biering-Sorensen Testr = −0.36, p = 0.001; Plank Testr = −0.55, p < 0.001). Derived allometric parameters for Biering-Sorensen and Plank Tests were b = −0.932 and −1.369, respectively. Allometric scaling with the derived allometric parameters was deemed appropriate at normalizing Biering-Sorensen and Plank Test scores because it caused the correlations between body mass and test scores to become insignificant (Biering-Sorensen Testr = 0.10, p = 0.354; Plank Testr = 0.14, p = 0.173). Allometric scaling with the theoretical allometric parameter was deemed inappropriate for normalizing Biering-Sorensen and Plank Test scores because it was not robust enough to get rid of the significant correlations between body mass and test scores (Biering-Sorensen Testr = −0.23, p = 0.034; Plank Testr = −0.43, p < 0.001). Allometric scaling with derived allometric parameters should be used to normalize Biering-Sorensen and Plank Test scores to body mass, particularly when attempting to account for changes in body mass across time intervals and differences in body mass across individuals.