Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Lie face down, arms at sides, palms up; engage core/glutes. Lift chest/arms off ground (legs down). Arms to sides (T-shape). Arms overhead (Y-shape), rotate shoulders (palms down). Reverse to sides/start. Lower. Repeat.
Use mat for comfort. Straight body line, arms/legs tucked. Head to floor (no neck strain). Rotate palms overhead (smooth, low wrist stress). No glute stick-out or chest lift.
MuscleTrain is actively being built. If something looks broken, or you have a suggestion, let us know — it really helps shape the app.