The Reliability of Tensiomyography for Assessment of Muscle Function: A Systematic Review

Tensiomyography (TMG) is a non-invasive tool used to assess skeletal muscle tissue, including Displacement (Dm), Contraction Time (Tc), Sustain Time (Ts), Relaxation Time (Tr), and Delay Time (Td). This tool can be used clinically to determine muscular response to exercise. PURPOSE: The purpose of this study was to investigate the reliability of TMG measurements. METHODS: Studies were identified from multiple databases and evaluated for inclusion. All studies underwent a quality assessment using the Modified Downs and Black checklist for assessing quality studies, and results were extracted from qualified articles. RESULTS: 635 studies were identified with 16 studies retained following full article reviews. 12 studies had poor quality, whereas 4 had fair quality. Within-subject reliability was reported in 11 articles, finding good to excellent reliability for all TMG measurements, except Ts and Tr, in 10 articles (CV ranges: Tc: 2.6-9.4, Ts: 5.3-21.3, Tr: 6.4-32.8, Td: 1.16-4.2, Dm: 8.0-14.8). Between-subject reliability was reported in 14 articles, finding fair to excellent reliability for all TMG measurements, except Td, in 12 articles (ICC ranges: Tc: .62-.98, Ts: .71-.95, Tr: .67-.96, Td: .47-.98, Dm: .86-.99). Inter-rater reliability was reported in 2 articles, finding good to excellent reliability for all TMG measurements (ICC ranges: Tc: .92, Ts: .96, Tr: .77, Td: .86, Dm: .96-.97). DISCUSSION: Non-invasive TMG has been found to have good to excellent absolute and inter-rater reliability for measuring the properties of skeletal muscles in multiple testing sites. Testing protocols should be taken into consideration including electrode distance, joint angle, and rest time.