Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Lie on back, knees shoulder-width, feet flat, heels 6–8 inches from glutes, toes forward, arms flat palms up. Raise hips high, engage glutes/abs, keep straight line shoulder-to-knee (no back arch). Squeeze glutes hard at top, hold briefly. Lower controlled, maintain tension.
Focus on glutes (not hamstrings/back): Feet closer if hams dominate; tuck hips/engage abs if back strains. Fully extend hips at top, flex glutes hard—align shoulders-knees-hips.
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