Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Start in tabletop, hands under shoulders, knees under hips. Fingers spread, palms flat, spine neutral. Inhale to Cow: drop belly, lift tailbone, open chest, gaze up. Exhale to Cat: round spine, tuck tailbone, pull belly button to spine, drop head. Alternate slowly, 8-12 reps, transitioning smoothly vertebra by vertebra.
Coordinate breath: inhale (Cow), exhale (Cat). Initiate movement from the tailbone, creating a wave-like motion up the spine. Keep arms straight; avoid bending elbows. Move within a comfortable range of motion; depth will increase with practice.
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