Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Band above knees. Supine on floor, arms 45° from torso. Bridge hips up (squeeze glutes, heels drive), push out on band. Lower to start. Repeat.
No low back arch: Squeeze glutes/posterior pelvis tilt. Straight knees-to-shoulders line at top. Exhale up—no back feel. Knees not past feet when pushing band. Can't feel glutes? Palpate/pause at peak.
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