PNF stretching

Question 1

What are the 3 stages of PNF stretching and which proprioceptor is involved?

Answer 1

Stage 1 - Partner extends the body limb to its limit/full range of motion
Stage 2 - Hold the stretch in this position for a few seconds, then isometrically contract the stretched muscle for 5-6 seconds
Stage 3 - Override the stretch reflex which allows a greater range of motion

Question 2

What to the muscle spindles do at stage one?

Answer 2

• Detect an increase in muscle length
• A nerve impulse is sent to engage the stretch reflex contraction of a muscle in response to overstretching
• Prevents overstretching

Question 3

What do the golgi tendons organ do at stage 2?

Answer 3

• Detect increased tension from isometric contraction in the muscle causing the muscle to relax
• This is autogenic inhibition

Question 4

How does autogenic inhibition work at stage 3?

Answer 4

• Sudden relaxation of muscle following high tension
• Negative feedback lengthening of muscle to prevent muscle tear