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Reference Appendix

Muscle Reference Guide & Proportions

A complete quick-reference guide to the key muscle groups and proportional landmarks in the system. Bookmark this page — it is the resource you will return to most often as your drawing deepens.

TORSO MUSCLES

  • Pectoralis Major — Fan-shaped chest muscle. Two pecs form the "4" trident shape.
  • Serratus Anterior — Finger-like slips along outer ribs below armpit. The "shark bite" texture.
  • Rectus Abdominis — The six-pack. Three rows of two blocks, ribs to pubic bone.
  • External Obliques — Side abs. Create the V-line from hip to pelvis — the athletic waist.
  • Trapezius — Large kite-shaped back muscle from skull to mid-spine. Neck/shoulder power.
  • Latissimus Dorsi — The "lats." Wing muscles creating the V-taper viewed from behind.
  • Erector Spinae — Two columns flanking the spine. Create the central back groove.

ARM & SHOULDER

  • Deltoid — Triangular shoulder cap. Three heads. Creates shoulder width.
  • Biceps Brachii — Two-headed front upper arm. The classic "flex" muscle.
  • Triceps Brachii — Three-headed rear upper arm. Larger than the bicep.
  • Brachioradialis — Dominant outer forearm. Creates the forearm's widest point.

LEG MUSCLES

  • Quadriceps — Four muscles of front thigh. Largest muscle group in the human body.
  • Hamstrings — Three rear thigh muscles. Visible from behind or in profile.
  • Gluteus Maximus — Primary buttock muscle. Large and visually dominant from rear.
  • Gastrocnemius — The visible calf muscle. Double-head creates its characteristic shape.
  • Tibialis Anterior — Front of shin. Creates the subtle bump beside the shin bone.

KEY PROPORTIONS

  • Shoulder width — ~2–2.5 head widths (heroic: up to 3×)
  • Figure height — ~7.5 heads tall (heroic: 8–9 heads)
  • Eye position — Exact vertical midpoint of the head
  • Elbow position — Level with the bottom of the rib cage
  • Wrist position — Level with the crotch when arm hangs naturally
  • Knee position — At the halfway point of the leg
  • Nose position — Halfway between eye line and chin
  • Ear height — From eye line to base-of-nose zone
Classical torso — front
Classical torso — front
Back view — major muscles
Back view — major muscles
Labeled anatomy diagram
Labeled anatomy diagram
Skull — three views
Skull — three views