Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Start on all fours, hands shoulder-width apart, fingers spread. Knees hip-width apart, stacked under hips, wrists under shoulders. Press palms firmly into the mat, lift hips, and curl toes to create an inverted V shape. Keep knees soft. Lengthen your spine, drawing chest toward thighs, ears between upper arms, creating a straight line from wrists to tailbone. If rounding your back, bend your knees more. Gradually straighten legs, sinking heels toward the floor (heel contact optional). Hold for 5-10 breaths, pressing hands firmly and drawing shoulder blades down on exhale, lengthening spine on inhale. Lower back to tabletop.
Actively press hands into the mat to engage serratus anterior; avoid shoulder shrugs. Spread fingers wide for wrist stability. Bend knees to maintain a flat back; hamstring flexibility will improve over time. Rotate upper arms outward (biceps forward) to create shoulder space and stability.
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