Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Start in a push-up position with your feet wider than your shoulders. Put your weight on the working arm, with that hand under your shoulder, and place the other hand out to the side with only the fingertips on the floor. Lower yourself by bending the working arm until your chest is near the floor, keeping your body in one line. Press back up, using the fingertips only as much as you need, and repeat, then do the same with the other arm.
Press mainly with the working arm; the other hand only keeps you steady and helps where you get stuck. Use fewer fingers or move the helping hand further out as you get stronger. Keep your hips level: don't let them twist toward the working arm. If you lose your balance, set your feet wider.
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