Plank

ANTI-EXTENSION · FOUNDATIONAL

Why it matters · Operator The plank trains the trunk to maintain a rigid neutral position under load. It is the single most transferable core position in tactical work, because almost every loaded carry, casualty drag, and overhead task requires holding the spine in this shape.

Why it matters · Longevity Plank endurance correlates with low-back pain prevention more strongly than any single mobility metric. People who can hold a plank for 60+ seconds have markedly fewer low-back complaints across the lifespan.

Form cues

• Forearms on the floor, elbows directly under shoulders
• Body in a straight line from heels to crown
• Glutes squeezed, quads engaged, ribs pulled down toward hips
• Breathe normally; do not hold your breath
• Stop the set when the line breaks, not when it gets uncomfortable

Common errors

• Hips sagging (line breaks; stop the hold or reset)
• Hips piking up (reduces difficulty; the line is the standard)
• Holding the breath (defeats the trunk training adaptation)

Path A scaling Begin with knee planks (knees instead of toes on the floor). Build to 3 × 20 sec on the knees, then move to full planks for 3 × 15 sec.

Path B scaling Standard plank from week one. Once 3 × 60 sec is easy, add the long-lever plank (hands instead of forearms) or weighted plank (small backpack on the hips).