Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Modified plank: forearms on floor, elbows under shoulders, hips up, knees/toes down. Protract scapula, pull forearms to midsection (lat tension); squeeze glutes/quads. Core on: ribs down, pelvis tucked, chin tucked. Straighten legs to full plank (legs together/hip-width). Squeeze triceps, straighten elbows to push-up; slowly lower. Repeat.
Bottom: arms arrow (not T). Rigid spine—moving plank. Glutes squeezed, abs braced (neutral ribs). Chin down (no forward look/head jut). Push thumbs together (pec activation). Chest/nose touch together. Explode from floor; full protraction top. Full reps—no shortcuts.
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