1) Golgi Tendon Organs – sense tension
2) Muscle Spindle Fibers – sense stretch
Proprioceptive Neuromuscular Facilitation (PNF)
1) Reciprocal Inhibition
→ Target muscle: gastrocnemius. Therapist engages isometric dorsiflexion for approximately 10 seconds, then passively stretches into plantarflexion.
• Indicated for cramping or when muscles are in spasm.
2) Contract-Relax, aka Tense-Relax
→ Target muscles: hamstrings. Therapist resists athlete's isometric hip extension for approximately 10 seconds, then passively flexes the hip on the relaxation.
• Indicated when stretch is inhibited; contracted soft tissue (hypertonic).
3) CRAC (Contract-Relax Antagonist-Contract)
→ Target muscles: hamstrings. Therapist resists athlete's hip extension for approximately 10 seconds. Athlete actively flexes the hip after the isometric contraction.
• Indicated when stretch is inhibited or muscle is hypertonic; &@2191; motor learning and strengthening of the antagonist muscle.
⌘ CRAC = CR + RI.
Contract target muscle 10-20˚. Breathe, resist (isoMETRic contraction!), relax, breathe, contract another 10-20˚ as required.