module 12

Question 1

biomechanics of biarticular muscles: what is the Lombard’s paradox

Answer 1

• the coactivation of RF and Ham
• cannot selectively extend hip without acting with equal force at the knee
• to occur simultaneously int he act of standing from seated, the net moment to an extensor moment at both the hip and the knee joints
• hence, RF moment needs to be greater than Ham moment at the knee joint (if both muscles generate the same tension)

Question 2

what is the role of biarticular muscles?

Question 3

what are different MTU force measurements? what are each pros and cons?

Answer 3

1. buckle transducter - invasive but a direct force sensor
2. fiber optic transductor - less invasive but an indirect measure
3. tendon holding - removeal from attachment - very invasive but direct (have control of activation, length, velocity)
   *active biart muscles may provide a route of force transmission from one joint to another