Start in a folded position, draw the knees toward the chest, lift the heels a few inches off the floor, and extend your arms in front of the body.
Unfold by separating the hips and torso. Push the legs out in front of you, extending the knees almost straight, and allow the trunk to descend approximately 30° toward from the ground.
Contract the abs to quickly pull the torso up and forward. Drive the knees to the chest, draw the trunk and hips together, and return to the folded position. Pause briefly, quickly pulse in and out of the folded position for the specified amount of time.
You should feel this working the abdominals, core, obliques, and hip flexors.
Hayden Steele has worked with models, fitness competitors, five first-round NFL draft picks, and over twenty professional athletes. He gets the most joy and satisfaction helping people become healthy, strong, and fit.