Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Start in a high plank. Engage your core, then lift your right arm and left leg straight, parallel to the floor. Hold briefly, return to plank. Alternate sides.
Maintain level hips, avoid rotation. Gaze slightly forward for neck alignment. Engage glutes and core for stability. For balance, perform on all fours. Breathe steadily.
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