Non-Invasive estimation of muscle fiber type using ultra Sonography

Abstract

Introduction: The aim of this study was to estimate the muscle fiber type i.e., fast/white muscle fibers and slow/red muscle fibers) on the basis of selected muscle architectural parameters i.e., Pen-nation angle, Muscle thickness and Fascicle Length of Rectus Femoris and Vastus Lateralis using ultrasound image analysis. Materials and Methods: In this work of investigation, a total sample comprised of 30 highly trained male athletes of Lakshmibai National Institute of Physical Education Gwalior, Madhya Pradesh was considered as sample for present investigation. Purposive sampling technique was employed for selecting sample, out of which 15 were marathon runners and 15 were 100-meter sprinters. The selected subjects’ age ranged between 19 to 25 years. Muscle architectural parameters such as Pen-nation angle, Fascicle length, and Muscle thickness were measured using a B-Mode ultrasonography method (Model-WIPRO GE VOLUSON E 6). Results: The developed estimate model explains 54.6% to 72.8% of the variation in muscle fiber type. Thus, the logistic regression equation developed was: - Log p/(1-p) = 10.955 - 3.278 (VL_FL) + 1.267 (VL_PA). Conclusion: The wald statistics obtained from the logistic model revealed that decreasing the vastus lateralis pen nation angle by one unit increases the likelihood of having white muscle fiber by 2.54 times, while increasing the Vastus Lateralis Fascicle Length by one unit increases the likelihood of having white muscle fiber by 0.62 times. In order to determine muscle fiber type on the basis of muscle architectural parameters Vastus lateralis pen-nation angle and fascicle length were the most discriminating variables among selected fiber types.