Anatomy Guide › Back
Latissimus Dorsi
The latissimus dorsi — Latin for 'broadest of the back' — earns its name honestly: it is the widest muscle in the human body. Each lat originates from an enormous territory including the lower half of the spine, the back of the pelvis, the lower ribs, and the tip of the shoulder blade, then sweeps upward and outward to twist into a compact tendon on the upper humerus. Seen from behind, well-developed lats form the V-shaped taper bodybuilders chase.
Functionally, the lat is the muscle of pulling. It draws the arm down and back with tremendous force — the power stroke of a pull-up, a swimmer's freestyle pull, a rower's drive, an axe swing. Because it links the pelvis and spine to the arm, it is also a bridge in the body's force chains: through the thoracolumbar fascia it cooperates with the opposite gluteal muscles, part of why a powerful throw or golf swing recruits the whole diagonal of the body.
The lat has a quieter medical career as the body's great spare part. Its size, flat shape, and single dominant blood vessel make it the workhorse of reconstructive surgery: latissimus flaps rebuild breasts after mastectomy and cover large defects elsewhere, and the muscle keeps working even after transplantation. Remarkably, people lose little everyday function when a lat is repurposed — other muscles cover for it in ordinary life, though elite climbing and swimming would miss it.
In Anamo, the latissimus dorsi is a heat-map giant: it touches the spine, ribs, scapula, and humerus. A lat guess casts a wide net across the whole back — often the most informative opening move in a back-region round.
- The widest muscle in the human body
- The prime mover of pull-ups, swimming strokes, and rowing
- Links the pelvis and spine to the arm in one force chain
- The workhorse flap of reconstructive surgery
Think you could find the latissimus dorsi on a 3D model? Play Anamo and test yourself — every guess is color-coded by how close it lands to the mystery structure.