Add a leg lift to the side plank and light up your obliques and hips.
Keep your hips high and stacked so the lift comes from the hip, not a wobble.
Raising the top leg from a full side plank strips away half your base and puts the obliques under one of the tougher holds bodyweight offers. The core keeps your body in a rigid diagonal while the leg lifts straight toward the ceiling, and any wobble spills the whole position. It is a natural next step once plain side planks stop being scary.
Noticeably. Lifting the top leg removes it from your base of support, so the bottom-side obliques and hip work far harder to keep you in line. If your regular side plank tops out around 45 seconds, you are ready to try it.
Height is not the goal, control is. Lift to roughly hip height or slightly above, pause, and lower without your hips dipping. A small controlled lift beats a high swing that breaks the plank.
Your body is escaping the work by coming out of the plank plane. Stack your shoulders and hips vertically, brace before the lift, and slow the leg right down until the position holds.
