A Comparison of Bilateral Muscular Imbalance Ratio Calculations Using Functional Tests

Bampouras, Theodoros M. and Dewhurst, Susan (2018) A Comparison of Bilateral Muscular Imbalance Ratio Calculations Using Functional Tests. Journal of Strength and Conditioning Research, 32 (8). pp. 2216-2220. ISSN 1064-8011

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Bilateral muscular imbalance can increase the risk of injury and negatively impact on sporting performance. Bilateral muscular imbalances are typically calculated as ([side 1 − side 2]/reference value) × 100, to provide a percentage value of the difference between limbs. Using different numerator (right-left or strong-weak) or reference values (left, right, strong, weak, average of the 2) could mask or inflate the true difference value. This study aimed to compare the bilateral muscular imbalance ratio calculations, using the absolute difference between limbs as the numerator and the 5 different options as reference values. Twenty-three males (21.6 ± 1.9 years, 1.80 ± 0.06 m, 80.5 ± 13.8 kg) and 11 females (20.8 ± 1.5 years, 1.62 ± 0.03 m, 68.0 ± 6.5 kg) performed the one-legged 6-m timed test and the one-legged triple-hop distance test. The 5 possible combinations were compared with a 2 (sex) × 2 (functional test) × 5 (calculation method) analysis of variance for each test. Significant differences ( p ≤ 0.05) were found between sex when the right leg was used as the reference value (men: 6.1%, women: 9.1%), and within calculation methods for men (range: 5.9–6.5%) and women (range: 8.4–9.4%), with low effect sizes (range: 0.07–0.26). These findings demonstrate that using a different reference value for calculating bilateral muscular imbalances does not result in a practically significant difference. These findings can be used to inform a more standardized calculation method which will afford conditioning coaches a more correct evaluation and monitoring of training and rehabilitation programs.

Item Type:
Journal Article
Journal or Publication Title:
Journal of Strength and Conditioning Research
Uncontrolled Keywords:
?? bilateral differenceinjuryisokinetic dynamometrylower limb asymmetryperformanceorthopedics and sports medicinephysical therapy, sports therapy and rehabilitation ??
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Deposited On:
10 Oct 2018 07:54
Last Modified:
15 Jul 2024 18:19