Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Sit on a stable, stationary chair (avoid chairs with wheels) with your feet apart and hands clasped in front of your chest. Without using your hands for assistance, press through your feet to stand up completely and hold the position. Bend your knees and slowly lower yourself back into the chair with total control.
Harder: Box squat
Use a chair that can't slide: put it against a wall if needed. Keep your feet flat and lean forward slightly before you stand up. Stand up fully, then sit down slowly instead of dropping into the chair. If you can't stand up without your hands, start with a higher seat.
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