Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Quadruped: hands under shoulders, toes tucked, knees under hips. Extend legs to push-up (straight legs, elbows extended, neutral head to floor). Descend: retract scapula, unlock elbows to upper arms parallel/chest to floor. Explode up: extend elbows, drive palms; clap hands mid-air, land start position. Repeat.
Bottom: arms arrow-shaped (not T). Rigid spine—like moving plank. Squeeze glutes/brace abs pre-descent (neutral ribs). Chin down (no forward look/head jut). Push thumbs together (pec activation). Chest/nose touch together. Explode away from floor; full protraction at top. Full reps only—no shortcuts.
MuscleTrain is actively being built. If something looks broken, or you have a suggestion, let us know — it really helps shape the app.