Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Begin in a low lunge, sliding the front shin across the mat (foot tucked or angled out). Extend the back leg straight, pressing the foot into the mat. Square hips, ensuring both hip points face forward; use a block under the back hip if needed. Bend the back knee, lifting the foot towards the ceiling, feeling a stretch in the back thigh. Press the thigh down, resisting hip rotation and elevation. Reach back and hook the top of the back foot into the crook of your elbow, sole facing up. Clasp hands overhead, sweeping the opposite arm up and back, reaching down behind the head. Hold, breathing deeply, lifting through the crown of the head, drawing shoulder blades down, and opening the chest. Release by unhooking the foot, lowering the leg, then releasing the arms. Rest in child's pose.
Prioritize hip squaring for stability. Avoid forcing the bind; use a strap if needed to prevent knee strain. Lift through the crown of the head *before* arching. Focus on deep, front rib breathing. Release in reverse order: foot, arms, then leg to prevent shoulder strain.
MuscleTrain is actively being built. If something looks broken, or you have a suggestion, let us know — it really helps shape the app.