EVMM Biomechanics

Question 1

Define the Force-Motion principle

Answer 1

Force is applied over a period of time. Increasing the time allows for greater acceleration or deceleration

Question 2

Two ways that motion affects force

Answer 2

1. 1. Increase time over which the force is applied

2. Increase the range of motion in the joints

Question 3

What are two forms of muscle, what function does each perform and name a specific muscle as an example of each form

Answer 3

1. Parallel – best for increasing the range of motion – Biceps
2. Pennate – best for isometric force – Abdominals

Question 4

Rest is one type of muscle action. What are the other three? . What is the main effect of each of these three actions?

Answer 4

1. Concentric – most force at slow speed
2. Eccentric most force at faster speed
3. Isometric – stabilizing force

Question 5

Define viscoelastic.

Answer 5

Tissue exhibits a time-dependent behavior under loading, reflecting the complex interactions between collagen fibrils, the non-collagenous matrix and water

Question 6

When is it best to use stretching. pre or post-exercise and why?

Answer 6

Post-exercise – prolonged stretching decreases muscle performance

Question 7

Why is it important to walk the horse for 10-20 minutes before training?

Answer 7

Viscoelasticity – cyclic loading makes the tendons better able to withstand higher loads

Question 8

Define active insufficiency.

Answer 8

Muscles generate the most force when they are near their resting length. Lengthening or shortening the muscle decreases the force it can produce. The muscles have more strength near the resting length because that is where there is the most cross-bridging between acting and myosin filaments.

Question 9

What is Force-Time delay? How does training affect force-time delay? What mechanism is used for trained movements?

Answer 9

Time delay between the intension to move and the motor action potential. Decreases it. Feed-forward mechanisms

Question 10

Does a large range of motion increase or decrease force produced?

Answer 10

Increase

Question 11

Define the stretch-shortening cycle.

Answer 11

Counter-movement is slowed by eccentric action immediately followed by concentric action in the intended direction

Question 12

How do most high force movements start?

Answer 12

Begins with movement in the opposite direction

Question 13

How does the stretch-shortening cycle increase force? (4)

Answer 13

1. 1. Contractile potentiation
2. Reflex potentiation
3. Storage of energy
4. Increase time of applied force

Question 14

What is the relationship between stability and mobility?

Answer 14

Dynamic balance