Flip the plank face-up on the straps and hold strong.
Squeeze your glutes to keep hips up, do not let them sag toward the floor.
Facing the ceiling with heels in the cradles, the reverse plank makes your core hold the body line from behind, resisting the sag that gravity and the free-swinging straps invite for every second of the hold. It is the mirror of a standard plank, training the backside chain of trunk control that front planks never load. It earns a place because most core programmes are entirely front-facing, and this fills the gap while punishing the smallest drop in hip height.
The other side of your trunk. Face-up, your core resists sagging from behind, so you train posterior trunk control and hip position instead of the front-body brace a standard plank drills.
Suspended heels can swing sideways, so you stabilise in every direction while holding the line. The floor version only asks you to hold up, this one asks you to hold still.
Squeeze your glutes hard for the entire hold, exactly as the cue says, and shorten the duration. Several crisp short holds beat one long sagging one.
