====== Muscles Most Used by Guitarists ======

Fingerpicking, strumming, and fretting require coordinated use of **extrinsic** (forearm) and **intrinsic** (hand) muscles. Below is a breakdown by function and location:

===== 🎸 1. Extrinsic Muscles (Forearm) =====

==== 🔹 Flexors (anterior compartment) ====
  * **[[Flexor digitorum superficialis]]** – Flexes middle phalanges (PIP joints) of fingers.
  * **[[Flexor digitorum profundus]]** – Flexes distal phalanges (DIP joints); enables full finger flexion.
  * **[[Flexor pollicis longus]]** – Flexes thumb.
  * **[[Flexor carpi radialis]] / [[Flexor carpi ulnaris]]** – Flex wrist (radial and ulnar deviation respectively).

==== 🔹 Extensors (posterior compartment) ====
  * **Extensor digitorum** – Extends fingers.
  * **Extensor indicis / digiti minimi** – Extend index and little fingers individually.
  * **Extensor pollicis longus / brevis** – Extend the thumb.
  * **Abductor pollicis longus** – Abducts the thumb (moves it away from the hand).

===== 🖐️ 2. Intrinsic Muscles (Hand) =====

==== 🔸 Thenar muscles (thumb control) ====
  * **Abductor pollicis brevis**
  * **Flexor pollicis brevis**
  * **Opponens pollicis**
  * **Adductor pollicis**
  -> Used heavily in picking, opposing thumb to fingers, and fast thumb articulation.

==== 🔸 Hypothenar muscles (little finger control) ====
  * **Abductor digiti minimi**
  * **Flexor digiti minimi brevis**
  * **Opponens digiti minimi**
  -> Assist in grip and hand positioning on the fretboard.

==== 🔸 Lumbricals and Interossei ====
  * **Lumbricals** – Flex MCP joints and extend IP joints; fine motor control.
  * **Dorsal interossei** – Abduct fingers (spread).
  * **Palmar interossei** – Adduct fingers (bring together).
  -> Critical for chord formation, finger independence, and precise articulation.

===== 🧠 Other Relevant Muscles =====
  * **Wrist stabilizers** – e.g. *extensor carpi radialis longus/brevis*
  * **Forearm rotators** – *pronator teres*, *supinator* (rotate hand position)
  * **Elbow flexors** – *biceps brachii*, *brachioradialis* (support posture and positioning)

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**Note:** Repetitive stress in these muscles is common in guitarists and may lead to conditions like tendinitis or carpal tunnel syndrome. Proper technique and stretching are essential.