Start in a push-up position and lift one leg off the floor, holding it straight and level with your body. Keeping the leg raised, lower your chest toward the floor and press back up, then switch legs. With only one foot on the ground your base shrinks, so your core and glutes have to work overtime to stop your hips from tipping to one side. If your raised foot is drifting toward the floor mid-rep, the set is over - reset and go again.

Works: chest, shoulders, triceps, core, glutes

Breathing: Inhale as you lower, exhale as you press back up.

Common Mistakes: Twisting the hips toward the grounded leg, letting the raised leg sag or bend, and cutting the range short because the balance gets uncomfortable at the bottom.

Make Easier: Practice Plank Leg Raises to build the single-leg stability first, or master regular Push-Ups before taking a foot away.

Make Harder: Try Push-Ups - Stacked to keep both feet stacked on one point, or Push-Ups - Dragon for the full-body version of unstable push-up work.