I don't believe we synthesize artificial atp.

there are no such thing as artificial muscles. Muscle is made up of calcium and rich blood.

An artificial heart is made from metal and plastic, and has a small pumping chamber lined by a special material that stops blood clots forming. An artificial heart that provides an extra ventricle to help pump blood around your body.

An artificial pacemaker works by detecting changes in the heart's rhythm. If it detects a 'problem' - it delivers a shock to the heart's muscle - returning the heartbeat to a regular beat.

When you are typing, you use several muscles, so there is no "antagonist muscle". A muscle pulls in 1 direction, causing a motion from a body part. The antagonist muscle is the muscle that causes the opposite motion. This is an artificial term! As typing is not a motion, but rather a complex sum of multiple motions, there is no answer to this question...