Kelly Lima1, Natália Martins1, Wagner Pereira2, Liliam Oliveira1. 1. Laboratory of Biomechanics of the Biomedical Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. 2. Laboratory of Ultrasound of the Biomedical Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Abstract
BACKGROUND: Supersonic Shear Imaging (SSI) is a technique which analyses quantitatively the tissue properties in real time. The relation between joint torque and Young's modulus (E) of the agonist muscles is important for obtaining stratification values and ranges of normality. The aim of this study was to evaluate the intra and intersessions reliability of the E values of the Achilles tendon and medial gastrocnemius muscle, bilaterally, during rest, and correlate them with the isometric plantarflexion peak torque. METHODS: Shear modulus maps were acquired bilaterally in Achilles tendon (AT) and medial gastrocnemius (MG) muscle of 24 healthy male volunteers. Two 5-second plantarflexion maximal voluntary contractions were performed with a 40-seconds interval and correlated with E values. RESULTS: a good intrasession reliability (intraclass correlation coefficient- ICC= 0.821-0.986) and a weak Pearson's correlation was found between E values and peak torque (r= 0.022 to -0.202) for both limbs (P > .05). CONCLUSION: E values cannot be predictive of the triceps surae force production in untrained men. It could be helpful, otherwise, to monitor a chronic strength adaptation after an exercise intervention or rehabilitation program. LEVEL OF EVIDENCE: IIb, individual cohort study.
BACKGROUND: Supersonic Shear Imaging (SSI) is a technique which analyses quantitatively the tissue properties in real time. The relation between joint torque and Young's modulus (E) of the agonist muscles is important for obtaining stratification values and ranges of normality. The aim of this study was to evaluate the intra and intersessions reliability of the E values of the Achilles tendon and medial gastrocnemius muscle, bilaterally, during rest, and correlate them with the isometric plantarflexion peak torque. METHODS: Shear modulus maps were acquired bilaterally in Achilles tendon (AT) and medial gastrocnemius (MG) muscle of 24 healthy male volunteers. Two 5-second plantarflexion maximal voluntary contractions were performed with a 40-seconds interval and correlated with E values. RESULTS: a good intrasession reliability (intraclass correlation coefficient- ICC= 0.821-0.986) and a weak Pearson's correlation was found between E values and peak torque (r= 0.022 to -0.202) for both limbs (P > .05). CONCLUSION: E values cannot be predictive of the triceps surae force production in untrained men. It could be helpful, otherwise, to monitor a chronic strength adaptation after an exercise intervention or rehabilitation program. LEVEL OF EVIDENCE: IIb, individual cohort study.
Authors: Stephen M Suydam; Elizabeth M Soulas; Dawn M Elliott; Karin Gravare Silbernagel; Thomas S Buchanan; Daniel H Cortes Journal: J Orthop Res Date: 2015-04-27 Impact factor: 3.494