One ball, narrow hands, and your triceps and chest scream.
Hands close on the ball means elbows stay tight, that is what hammers your triceps.
Stacking both hands on a medicine ball narrows your base to a single wobbling point, so your chest presses while your triceps and shoulders fire constantly just to keep the ball still. The close hand position keeps your elbows tucked, shifting extra work onto the triceps compared with a standard push up. It is a bodyweight press and a stability drill in one, no kit beyond the ball.
Same narrow-hand triceps bias, plus instability. The floor never moves, the ball always threatens to, so your pressing muscles and shoulders work overtime stabilising every inch of the rep. It is the harder sibling.
Spread your fingers around the curve and grip the ball like you own it, stack your shoulders directly above it, and widen your feet for a bigger base. A slightly softer or heavier ball also rolls less than a light rubber one.
Only after regular push ups are comfortable for solid sets. Until then, do them with hands on the ball but knees down, or park the ball in a corner so it cannot travel. Instability only helps once the basic press is strong.
