Strathprints logo
Strathprints Home | Open Access | Browse | Search | User area | Copyright | Help | Library Home | SUPrimo

Tensile properties of the in vivo human gastroenemius tendon

Maganaris, C.N. and Paul, J.P. (2002) Tensile properties of the in vivo human gastroenemius tendon. Journal of Biomechanics, 35 (12). pp. 1639-1646. ISSN 0021-9290

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

In the present experiment we obtained the tensile properties of the human gastrocnemius tendon, a high-stressed tendon suitable for spring-like action during locomotion. Measurements were taken in vivo in six men. The gastrocnemius tendon elongation during tendon loading−unloading induced by muscle contraction−relaxation was measured using real-time ultrasonography. Tendon forces were calculated from the moment generated during isometric plantarflexion contraction, using tendon moment arm length data obtained in vivo with the tendon travel method. Tendon stiffness data were calculated from the slope of the tendon force−elongation curve, and were then normalized to the tendon's original dimensions, obtained from morphometric analysis of sonographs, to estimate the tendon Young's modulus. Mechanical hysteresis values were obtained from area calculations by numerical integration. The elongation of the tendon increased curvilinearly with the force acting upon it, from 1.7±1 mm (0.8±0.3% strain) at 87.5±8.5 N to 11.1±3.1 mm (4.9±1% strain) at 875±85 N. The tendon Young's modulus and mechanical hysteresis were 1.16±0.15 GPa and 18±3%, respectively. These values fall within the range of values obtained from in vitro experiments and are very similar to the respective values recently obtained from in vivo measurements in the less highly stressed human tibialis anterior tendon (1.2 GPa and 19%), thus indicating that the material properties of tendon are independent of physiological loading and function. Combining the present tendon force−elongation data with previously reported Achilles tendon force data recorded during walking indicates that the gastrocnemius tendon would provide not, vert, similar6% of the total external work produced by the locomotor system. This estimate illustrates the contribution of passive elastic mechanisms on the economy and efficiency of walking. The contributions would be greater in more active exercise such as running.

Item type: Article
ID code: 6751
Keywords: ultrasonography, Young's modulus, Mechanical hysteresis, Viscoelasticity, Locomotion, Bioengineering, Human anatomy, Biomedical Engineering, Rehabilitation, Orthopedics and Sports Medicine, Biophysics
Subjects: Technology > Engineering (General). Civil engineering (General) > Bioengineering
Science > Human anatomy
Department: Faculty of Engineering > Bioengineering
Related URLs:
    Depositing user: Strathprints Administrator
    Date Deposited: 27 Aug 2008
    Last modified: 04 Sep 2014 14:59
    URI: http://strathprints.strath.ac.uk/id/eprint/6751

    Actions (login required)

    View Item