title: Changes in muscle stiffness during contraction recorded using ultrasonic waves.
mesh_terms: D000205:Actomyosin / Q000502:physiology; D000818:Animals; D066298:In Vitro Techniques; D009119:Muscle Contraction; D011892:Rana catesbeiana; D014463:Ultrasonography
chemical_list: D000205:Actomyosin