Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stance foot straight ahead, toes near floor kettlebell. Lift free foot off ground (stays up). Straighten stance leg, pull kneecap up, squeeze glutes. Pick bell: Bend stance knee/hip hinge (or straight leg), grab with both hands, scapulae back, stand squeezing glutes. Drag bell down leg to ground (not on toes/too far forward); free leg up (touch ground if balance lost). Stand tall: Squeeze glutes/hams, straighten stance leg. Repeat, then switch legs.
Flat back, hip hinge (not spine); chest up, eyes 3ft forward. Straight line: Raised leg-spine-head. No twist: Back toes down. Standing leg soft (not locked). Hinge to hamstring limit—no reach/shoulder drop. Firm grip for shoulder stability.
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