The mechanical properties of muscle-tendon units have been investigated most frequently using in vitro preparations. Testing of elastic properties most often utilises quasi-static protocols. Dynamic protocols have also been used, particularly in studies that seek also to determine viscous properties.
Several methods have been developed for testing the mechanical properties (usually elastic or pseudo-elastic properties) of human muscle-tendon units in vivo. Changes in length of human gastrocnemius muscle-tendon units may be estimated from changes in ankle and knee angles if moment arms are known. Fascicle lengths can be measured with ultrasound imaging or MRI. Recently methods have been developed for measuring sarcomere lengths using invasive and minimally invasive techniques. Achilles tendon force can be measured using invasive methods such as fibre optic transducers. The length-tension properties of the Achilles tendon can be estimated using non-invasive methods during isometric contractions.
This workshop focuses on a method developed by our research team for non-invasive measurement of the passive length-tension properties of human gastrocnemius muscle-tendon units , as well as length-tension properties of muscle fascicles and tendons . The method involves measuring ankle stiffness at a range of knee angles.