Muscles worked
Abs, lower back, shoulders, glutes.
Why plank works
Unlike a crunch, which moves the spine, a plank trains your core to resist movement — bracing against gravity trying to pull your hips down or up. That "anti-extension" strength is closer to what your core actually does in daily life and in most other exercises, which is why coaches treat it as a foundational stability drill rather than just an ab exercise.
How to do plank
- Place your forearms on the floor, elbows under your shoulders.
- Extend your legs back, toes on the floor.
- Form a straight line from head to heels.
- Brace your abs and squeeze your glutes.
- Hold, breathing steadily.
What you should feel
A deep, spread-out tension through the abdomen, glutes and shoulders — not a pinch or ache in the lower back. Lower-back discomfort almost always means the hips have dropped and the spine is hanging rather than being held. Reset rather than pushing through it.
Form tips
- Imagine pulling your elbows toward your toes.
- Keep your hips level with your shoulders.
- Quality over time — a solid 30 seconds beats a sloppy 2 minutes.
Why longer is not better
The instinct with planks is to chase duration, and it is the wrong instinct. Once you can hold a genuinely good plank for about sixty seconds, adding minutes trains endurance in a position you will never need to hold for minutes, and it almost always comes at the cost of position — the hips sink, the spine hangs off its ligaments, and you are resting on your skeleton rather than working your muscles.
A better test of whether your plank is worth doing: can you hold it for thirty seconds while actively squeezing your glutes, bracing your abdomen, and pulling your elbows toward your toes without them moving? Most people cannot, and that version is far more useful than a limp three-minute hold.
Set up by placing your elbows directly under your shoulders, tucking your pelvis slightly so your lower back flattens, then squeezing your glutes hard. The glute squeeze is the piece most people skip, and it is what stops the hips from sagging. Push the floor away through your forearms to spread your shoulder blades rather than letting your chest sink between them.
When sixty seconds becomes comfortable, take away stability instead of adding time: lift one foot, then one arm, then progress to alternating limb lifts. That is where the exercise keeps paying.
Sets and reps
3 holds of 20–45 seconds. Build time gradually.
Programming it into your week
Two to four sets of twenty to sixty seconds, most days if you like — the plank recovers quickly. Quality beats duration comprehensively: thirty seconds of genuine full-body tension does more than two minutes of sagging. When you can hold good form for a minute, add difficulty rather than time.
How to progress
Knees down first if a full plank collapses. Then full plank, then longer holds to sixty seconds, then start subtracting stability: lift one foot, then one hand, then move to a forearm plank with alternating limb lifts. Adding a weight plate on the back is the loading route if you prefer.
Variations & progressions
- Easier: plank on your knees or hands elevated.
- Harder: longer holds, shoulder taps, or plank reaches.
- Try side planks for the obliques.
How it compares
The plank trains the core to resist movement, which is closer to what the core actually does in life than the flexion trained by sit-ups. Against a dead bug or bird-dog, it is more static and demands less coordination; against a side plank, it neglects the lateral and rotational work that the obliques need.
Equipment
None. A mat makes the elbows considerably more comfortable.
Looking for a full routine? Try our beginner bodyweight workout.