Dynamic viscoelastic behavior of lower extremity tendons during simulated running.
The aim of this project was to see whether the tendon would show creep during long-term dynamic loading (here referred to as dynamic creep). Pig tendons were loaded by a material-testing machine with a human Achilles tendon force profile (1.37 Hz, 3% strain, 1,600 cycles), which was obtained in an earlier in vivo experiment during running. All the pig tendons showed some dynamic creep during cyclic loading (between 0.23 +/- 0.15 and 0.42 +/- 0.21%, means +/- SD). The pig tendon data were used as an input of a model to predict dynamic creep in the human Achilles tendon during running of a marathon and to evaluate whether there might consequently be an influence on group Ia afferent-mediated length and velocity feedback from muscle spindles. The predicted dynamic creep in the Achilles tendon was considered to be too small to have a significant influence on the length and velocity feedback from soleus during running. In spite of the characteristic nonlinear viscoelastic behavior of tendons, our results demonstrate that these properties have a minor effect on the ability of tendons to act as predictable, stable, and elastic force transmitters during long-term cyclic loading.
De Zee
M
M
Center for Sensory-Motor Interaction, Aalborg University, 9220 Aalborg, Denmark. mdz@miba.auc.dk
Bojsen-Moller
F
F
Voigt
M
M
D000125:Achilles Tendon / Q000502:physiology*; D000818:Animals; D004548:Elasticity; D005246:Feedback; D005552:Forelimb / Q000502:physiology*; D006801:Humans; D023421:Models, Animal; D009043:Motor Activity / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology; D012420:Running / Q000502:physiology*; D013314:Stress, Mechanical; D013552:Swine; D013710:Tendons / Q000502:physiology*; D014783:Viscosity