THE ANKLE ERGOMETER - A NEW TOOL FOR QUANTIFYING CHANGES IN MECHANICAL-PROPERTIES OF HUMAN MUSCLE AS A RESULT OF SPACEFLIGHT

A mechanical device for studying changes in mechanical properties of h uman muscle as a result of spaceflight is presented. Its main capaciti es are to allow during a given experiment investigation of both contra ctile and visco-elastic properties Of a musculo-articular complex usin g respectively isometric contractions, isokinetic movements, quick-rel ease tests and sinusoidal perturbations. This device is a motor driven ergometer associated to an experimental protocol designed for pre- an d post-flight experiments. As microgravity preferentially affects post ural muscles, the apparatus was designed to test muscle groups crossin g the ankle joint. Three subjects were tested during the Euromir' 94 m ission. Preliminary results obtained on the european astronaut are bri efly reported. During the next two years the experiments will be perfo rmed during six missions.