Reliability and measurement error of tensiomyography to assess mechanical muscle function: A systematic review

Abstract

Interest in studying mechanical skeletal muscle function through tensiomyography (TMG) has increased in recent years. This systematic review aimed to (a) report the reliability and measurement error of all TMG parameters [i.e., maximum radial displacement of the muscle belly (Dm), contraction time (Tc), delay time (Td), half-relaxation time (1/2 Tr), and sustained contraction time (Ts)] and (b) to provide critical reflection on how to perform accurate and appropriate measurements for informing clinicians, exercise professionals, and researchers. A comprehensive literature search was performed of the Pubmed, Scopus, Science Direct and Cochrane databases up to July 2017. Eight studies were included in this systematic review. Meta-analysis could not be carried out due to the low quality of the evidence of some studies evaluated. Overall, the review of the nine studies involving 158 participants revealed high relative reliability [intra-class correlation (ICC)] for Dm (0.91-0.99); moderate to high ICC for Ts (0.80-0.96), Tc (0.70-0.98), and 1/2 Tr (0.77-0.93); and low to high ICC for Td (0.60-0.98), independently of the evaluated muscles. Additionally, absolute reliability [coefficient of variation (CV)] was low for all TMG parameters except for 1/2 Tr (CV = >20%) while measurement error indexes were high for this parameter. In conclusion, this study indicates that three of the TMG parameters (Dm, Td and Tc) are highly reliable, whereas 1/2 Tr demonstrate insufficient reliability, and thus should not be used in future studies.