How to Do a Plank Properly: A Beginner's Guide

The plank looks like the easiest exercise there is. You get down on the floor and stay still. Yet it is one of the moves people most often get wrong, usually by chasing a big number on the clock while their hips sag and their lower back takes the strain. This guide, part of our series on doing the big movements properly, keeps things simple. You will learn which muscles you are working, how to set up step by step, how to climb from a knee plank to a full plank to a side plank, and how to follow a 4-week plan built on short, good-quality holds.

What muscles does a plank work?

A plank is a hold, not a movement. Your muscles work hard to keep you still, which is why it can feel tough even though nothing appears to be happening. The main work is done by the muscles around your middle: the rectus abdominis at the front (the six-pack muscle), the transverse abdominis underneath it (a deep muscle that wraps around your waist like a belt) and the obliques down your sides. Together they stop your lower back from dipping towards the floor.

They do not work alone. Your glutes and the fronts of your thighs keep your hips and legs straight, while your shoulders, chest and the muscles around your shoulder blades hold your upper body up. Turn onto your side for a side plank and the effort shifts to your obliques and the muscles on the outside of your hip, which help keep your pelvis level when you stand on one leg.

How do you do a plank with good form?

These cues are for the standard forearm plank. Run through them from the floor up each time you set up.

• Elbows. Lie face down and place your elbows directly under your shoulders, with your forearms flat on the floor and pointing forwards. Keep your hands relaxed rather than clasped tightly together.
• Feet. Tuck your toes under with your feet about hip-width apart. A wider stance is a little easier, feet together is a little harder.
• Lift. Press your forearms into the floor and lift your hips until your body makes one straight line from your head to your heels.
• Hips and ribs. Gently tuck your tailbone under, as if you were pulling your belt buckle towards your chin, and draw your ribs down. This flattens the arch in your lower back.
• Squeeze. Squeeze your glutes, tighten your thighs and brace your stomach as if someone were about to poke you in the belly.
• Shoulders. Push the floor away so your chest does not sink between your shoulder blades.
• Head. Keep your neck long and look at the floor between your hands.
• Breathing. Take slow, steady breaths while you stay braced. If you can only hold the position by holding your breath, the plank is too hard or too long for now.

One practical tip: film yourself from the side or set up next to a mirror. Most people feel straight when their hips are actually too low or too high, and a five-second clip settles it.

What is the best plank progression for beginners?

You do not have to start on your toes. A plank gets easier when you shorten the distance between your elbows and the point where your lower body touches the floor, so you can pick the version that matches your strength today and climb from there.

• Rung 1: Knee plank. Set up exactly as above, but rest your knees on a mat or folded towel. Aim for a straight line from your head to your knees, with your hips pushed forward rather than bent. If this is still too much, put your forearms on a sofa or sturdy bench instead, which takes even more weight off.
• Rung 2: Full plank. The forearm plank from your toes. Start with holds of about 10 seconds and build up. You can also do it on your hands with straight arms, known as a high plank. This is the top position of a push-up, and it tends to ask more of your wrists and shoulders and slightly less of your abs.
• Rung 3: Side plank. Lie on your side with your elbow under your shoulder. Begin with your knees bent and your bottom knee on the floor, then lift your hips so your body forms a straight line. When that feels solid, straighten your legs and stack your feet, or place the top foot just in front of the bottom one for balance. Keep your hips forward and your top shoulder stacked over the bottom one. Always train both sides.

Move up a rung when you can do 3 holds of 30 seconds at your current level without your form changing. There is no rush. A tidy knee plank does more for you than a full plank with a sagging back.

How long should you hold a plank?

Shorter than you might think. Plank holds lasting several minutes make good social media, but nobody needs them. Once your form slips, your abs have stopped doing the job and your lower back is picking up the slack, so the extra seconds are not buying you much. Professor Stuart McGill, a well-known spine researcher, has argued that repeated holds of around 10 seconds suit most people better than one long grind. You do not have to stick to exactly 10 seconds, but the principle is a good one: quality first, time second.

Here is a simple guide to sets and holds:

• Starting out. 3 to 5 holds of 10 to 20 seconds, with 20 to 30 seconds of rest between them.
• Building up. 3 holds of 30 to 45 seconds, resting for about as long as you held.
• Side planks. 2 to 3 holds of 10 to 20 seconds on each side.
• How often. 2 to 3 times a week is plenty. The whole thing takes about five minutes.

End every hold when your form starts to fade, not when you collapse. Once you can hold a clean plank for 45 to 60 seconds, make it harder rather than longer: move up a rung, lift one foot a few centimetres off the floor, or try slow shoulder taps from a high plank.

What does a 4-week beginner plank plan look like?

Follow this plan three times a week with a day off in between, for example Monday, Wednesday and Friday. Rest for 20 to 30 seconds between holds. If a week feels too hard, repeat it. Everyone moves at a different speed.

By the end of week 4 you should have a solid full plank and the start of a full side plank. If you are not there yet, stay on the knee versions for another week or two. That is completely normal.

What are the most common plank mistakes, and how do you fix them?

• Sagging hips. Your lower back dips towards the floor. Tuck your tailbone, squeeze your glutes and shorten the hold. If it keeps happening, drop to your knees.
• Hips too high. Your bum lifts into the air, which takes the work away from your abs. Lower your hips until your shoulders, hips and heels line up.
• Sinking shoulders. Your chest drops between your shoulder blades. Push the floor away with your forearms.
• Craning your neck. Looking up at the wall or letting your head hang both pull you out of line. Look at the floor between your hands.
• Holding your breath. Breathe slowly through your nose or mouth while you stay braced.
• Chasing the clock. Hanging on for a longer time with poor form teaches your body the wrong position. Stop, rest and go again.

How do planks fit into a hybrid week with running?

Easily. Planks do not tire your legs and they take five minutes, so they slot in almost anywhere. The simplest options are straight after an easy run, while you are already warm, or at the end of a strength session. A steady trunk may also help you hold your posture when you get tired late in a run, and side planks train the hip muscles that keep you level each time you land on one foot. The one thing to avoid is a hard core session just before a long run or a fast session, when you want your trunk fresh.

A simple week could look like this:

• Monday. Strength session, finishing with front planks.
• Tuesday. Easy run.
• Wednesday. HIIT session or an easy day, plus five minutes of planks and side planks.
• Thursday. Easy run.
• Friday. Strength session, finishing with planks and side planks.
• Saturday. Rest or a walk.
• Sunday. Long run.

At Edge we treat running, strength and HIIT as one plan rather than three separate ones, so core work like planks sits alongside your runs instead of competing with them. Edge is free to use, and Edge Pro, from £19.99 a month with a free 7-day trial, gives you a fully personalised plan across running, strength, HIIT and mobility, ready in 15 minutes, with a real coach to message anytime if you are not sure when to move up a rung.

This article is general guidance, not medical advice. If you are new to exercise, returning from injury, pregnant, or managing a health condition, speak to your GP before starting, and see a physio for any niggle that does not settle.