Reproducibility of muscle response measurements using tensiomyography in a range of positions

Abstract

Aim. To verify that tensiomyography (TMG) is a reliable method for the non-invasive assessment of the contractile properties of muscles, independently of sensor position. Methods. TMG was used to assess radial displacement of the anterior rectus femoris in the dominant leg of 25 individuals (age: 25.7 ± 4.7 years). The measurements were taken in three positions; one position was mid-point while the other two were at a ±2 cm distance from the latter. The following parameters were measured: maximum radial displacement of the muscle belly (Dm), contraction time (Tc), reaction time (Td), contraction sustain time (Ts) and relaxation time (Tr). Results. Analysis of reproducibility yielded the following Cronbach alpha coefficients: 0.970, 0.920, 0.897, 0.976 and 0.984 for Tc, Dm, Td, Ts and Tr, respectively. Conclusions. TMG is shown to be a tool with a high degree of reproducibility for assessing the contractile properties of muscles. To ensure maximum reliability on repeated measurements, it is necessary to adhere closely to a measurement protocol in order to avoid altering the muscle response; in this respect, the positioning of the sensor and the complete relaxation of the muscle are two factors of fundamental importance.