Core
Core musculature
Short definition
Trunk stabilizers: rectus, obliques, transversus, erectors, diaphragm.
Full definition
The «core» is the group of trunk and pelvic stabilizers that brace the spine and transmit force between the lower and upper body: rectus and obliques, transversus abdominis, multifidus, erector spinae, diaphragm. Gross mass ≈ 4–6 % (at 20–25 % body fat, rough estimate). A strong core underlies squats, deadlifts, and any bar hold: it preserves posture, transmits load and protects the lumbar spine.
Examples
Crunks and plank — basic core work.