Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Start in plank, straight head-to-heels. Hands under chest, narrower than shoulders. Tuck elbows close. Lower chest to floor. Push up through palms. Keep straight line throughout.
Engage core for straight body line. Tuck elbows to sides for triceps focus. Control descent and ascent fully. Too hard? Do on knees with good form. Inhale down, exhale up. Avoid: Wide hands/elbows, sagging/lifting hips, incomplete range, shrugging shoulders, rushing, poor alignment.
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