Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet shoulder-width apart. Hold dumbbells or a barbell (optional). Engage your core, keep your back straight. Lift heels, rising onto the balls of your feet. Squeeze calves at the top. Lower heels with control. Repeat.
Maintain balance and control. Keep knees slightly bent. Increase intensity with single-leg work or added weight. Avoid bouncing; pause at the top. Breathe: inhale on the lower, exhale on the lift.
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