1.3 PNF (proprioceptive Neuromuscular Facilitation)

Question 1

Role of muscle spindles in PNF

Answer 1

• sensitive proprioceptors that lie between skeletal muscle fibres.
• called stretch receptors = provide info to the CNS about how fast and how far a muscle is being stretched
• the CNS sends impulse back to the muscle telling it to contract, triggers the stretch reflex
• this reflex action causes the muscle to contract to prevent over-stretching and reduces injury

Question 2

Role of Golgi tendon organs in PNF

Answer 2

• found between muscle fibres and tendon
• defect level of tension in a muscle
• when the muscle is contracted isometrically in PNF, they sense the increase muscle tension
  … send inhibitory signals to the brain which allows the antagonist muscle to relax and lengthen
• known as autogenic inhibition

Question 3

PNF in practise

Answer 3

A) perform a passive stretch with help of partner, extends the leg until tension is felt. Stretch is detected by the muscle spindles. If the muscle is being stretched too far, then a stretch reflex shoulder occur

B) isometrically contracts the muscle for 10s by pushing against the partner who supplies enough resistance to hold the leg in stationary position.

C) the leg is lifted again, the Golgi tendon organs are responsible for the antagonist muscle relaxing. Means the leg stretch’s further, this process can be repeated until no more gains are possible