🦶 Zone 4,1 – Arch Front Inner (Medial Longitudinal Arch / Navicular Region)
This zone spans the front section of the medial longitudinal arch, just behind the 1st metatarsal and over the navicular bone. While it rarely contacts the floor directly, it’s a core stabilizer and tension controller for medial poise and rise.
🔬 Muscle Support
| Muscle |
Size |
Action |
Relevance |
| Tibialis posterior |
✅ Large |
Elevates medial arch |
Major dynamic stabilizer |
| Abductor hallucis |
✅ Moderate |
Pulls big toe medially, supports arch |
Supports torque transmission |
| Flexor hallucis longus |
✅ Large |
Runs under arch |
Passive tension controller |
| Plantar fascia (medial band) |
✅ Strong |
Connects heel to metatarsals |
Resists flattening |
| Spring ligament |
⚠️ Ligament |
Connects calcaneus to navicular |
Elastic arch support |
Summary: This zone isn’t about contact — it’s about load transfer and arch integrity under torque.
🔬 Muscle Mass Comparison
- Well-supported by large extrinsic muscles
- Arch height and rebound depend on this region
- Acts as a load spring, resisting excessive pronation and collapse during rise
⚖️ Torque Generation vs Resistance
- Torque generation? ❌ No — not used to push
- Torque resistance? ✅ Yes — excellent lateral and medial dampening
- Feedback quality? ✅ High, via strain and tension (not pressure)
📉 Collapse Risk
- Low, as long as tibialis posterior is active
- Collapse occurs if arch flattens (common in tired or untrained dancers)
- Medial strain here often signals compensating for poor poise elsewhere
🩰 Use in Dance
- Supports:
- Controlled rise mechanics
- Directional torque modulation
- Arch rebound during soft landings
- Engaged constantly during sustained balance and rotational control
🧠 Teaching Insight
“You’ll never feel 4,1 on the floor — but you’ll definitely feel it if it fails.”
Train dancers to feel the arch lifting, not just the toes pressing. That lift is coming from here.
✅ Verdict 🟢 (Green)
- Torque Handling: ✅ Strong
- Muscle Support: ✅ Deep, extrinsic
- Feedback Quality: ✅ Strain-based
- Stability: 🟢 Reliable in motion