What are the best core exercises?

The most useful core exercises train the trunk to resist movement rather than create it. The dead bug, bird dog, side plank, front plank, Pallof press, hollow hold, hanging knee raise, suitcase carry, ab wheel rollout and reverse crunch cover all three directions a core has to brace against: extension, rotation and sideways bending.

What muscles make up the core?

Far more than the abdominals. The core includes the rectus abdominis, the internal and external obliques, the deep transverse abdominis, the erector spinae and multifidus along the spine, the quadratus lumborum, the diaphragm above and the pelvic floor below. The glutes are usually trained alongside them because they control the pelvis.

How long should I hold a plank?

Shorter than most people think. Spine researcher Stuart McGill recommends repeated holds of around ten seconds with brief rests rather than one long hold, because form degrades once fatigue sets in and a sagging plank loads the lower back. Three sets of three to five ten-second holds builds more usable endurance than a single two-minute effort.

Do core exercises burn belly fat?

No. Spot reduction has not been supported by controlled research. Training the abdominal muscles makes them stronger and thicker but does not preferentially burn the fat sitting over them. Visible abdominal definition comes from overall body fat levels, which are driven mainly by diet and total activity.

Are sit-ups bad for your back?

Repeated full spinal flexion under load is what raises the concern. Stuart McGill's laboratory work on spinal segments showed that repeated bending cycles can damage the discs, which is why many strength coaches replaced sit-ups with braced exercises such as the dead bug and curl-up. Sit-ups are not dangerous for everyone, but they are a poor trade for people with existing back pain.

How often should I train my core?

Three to four sessions a week of ten to fifteen minutes works well for most people, and the core recovers quickly because it is built for endurance. NHS guidance recommends muscle-strengthening activity on at least two days a week as a minimum across the whole body, and core work counts towards that.

The Best Core Exercises for Strength, Stability and a Healthier Back

10 minutes ago

5 min read

Stuart McGill spent three decades at the University of Waterloo putting spines under load in a laboratory and watching what broke them. His finding reorganised how coaches think about abdominal training: the damage came from repeated bending, not from heavy loads. Which made the sit-up, a movement built entirely from repeated bending, a strange choice for the exercise everyone did a hundred of. His replacement list runs to three exercises, none of which involves curling up off the floor.

Key Takeaways

● The core's job is mostly to stop movement, so the best exercises train it to resist rather than to flex.

● Train all three directions: anti-extension, anti-rotation and anti-lateral flexion. Most people only ever do the first.

● The McGill Big 3 are the curl-up, side plank and bird dog, chosen for spine safety rather than burn.

● Short repeated holds beat one long plank. Form collapses before the muscle does.

● Core work will not burn belly fat. Spot reduction has never held up under controlled testing.

● Ten to fifteen minutes, three or four times a week is enough.

What the core actually is

The word gets used as a polite synonym for abdominals, which is why so many core routines are just crunch variations.

Woman holding a forearm plank on a mat in a bright living room, with dumbbells, a water bottle, and a kettlebell nearby.

The real structure is a box. The diaphragm forms the lid, the pelvic floor the base, the transverse abdominis wraps around the front and sides like a weightlifting belt, and the erector spinae and multifidus run up the back. The obliques handle twisting and side bending, the quadratus lumborum sits deep in the lower back, and the rectus abdominis, the six-pack muscle everyone pictures, is one panel on the front of the box.

What that box does, nearly all the time, is hold still. When you carry shopping in one hand, your core stops you tipping sideways. When you reach overhead, it stops your lower back arching. Train it to resist and you train the thing it does. Train it only to crunch and you build one movement it rarely performs.

The three directions worth training

Category	What the core resists	Exercises
Anti-extension	The lower back arching	Dead bug, front plank, ab wheel rollout
Anti-rotation	The torso twisting	Pallof press, bird dog, renegade row
Anti-lateral flexion	The body bending sideways	Side plank, suitcase carry, Copenhagen plank

Most home routines are entirely anti-extension. Adding one anti-rotation move and one carry changes more about how your body feels than another set of crunches ever will.

The ten best core exercises

#	Exercise	Trains	How to do it	Sets and reps
1	Dead bug	Anti-extension	On your back, arms up, knees at 90°. Lower one arm and the opposite leg while keeping your lower back flat to the floor	3 x 8 per side, slow
2	Bird dog	Anti-rotation	On all fours, extend opposite arm and leg. Keep hips level, as if balancing a glass on your lower back	3 x 8 per side, hold 5 seconds
3	Side plank	Anti-lateral flexion	Forearm under shoulder, hips stacked and lifted. Knees down if the full version sags	3 x 10 to 20 seconds per side
4	Front plank (RKC style)	Anti-extension	Squeeze glutes, tuck the pelvis, pull elbows towards toes without moving them. Should be hard at 10 seconds	3 x 3 reps of 10 seconds
5	Pallof press	Anti-rotation	Stand side-on to a cable or resistance band at chest height, press straight out and resist the twist	3 x 10 per side
6	McGill curl-up	Spine-sparing flexion	One knee bent, hands under the lower back, lift head and shoulders a few centimetres only	3 x 5, hold 8 seconds
7	Hollow body hold	Anti-extension	Lower back pressed down, arms and legs extended. Bend the knees to regress	3 x 15 to 30 seconds
8	Hanging knee raise	Hip flexion with control	Hang from a bar, raise knees without swinging. Lower slowly	3 x 8 to 12
9	Suitcase carry	Anti-lateral flexion	Walk 20 metres holding one heavy weight. Do not lean away from it	3 x 20 metres per side
10	Ab wheel rollout	Anti-extension, advanced	From the knees, roll out as far as you can without the back arching. Stop well before failure	3 x 6 to 10

The first six are accessible to almost anyone. The ab wheel is the one people attempt too early, and a rollout performed with a sagging lower back is one of the quickest ways to aggravate it.

A note on the plank

The two-minute plank became a benchmark for no particularly good reason. McGill's argument is that endurance is built through repetition, not through grinding out a single hold while the hips drift towards the floor. A plank that is genuinely hard at ten seconds, with the glutes locked and the ribs pulled down, trains more than a lazy ninety-second one.

A ten-minute routine

Do this three or four times a week. No equipment beyond a mat.

● Dead bug, 3 sets of 8 per side

● Bird dog, 3 sets of 8 per side with a 5-second hold

● Side plank, 3 sets of 15 seconds per side

● Front plank, 3 sets of 3 reps of 10 seconds

● Hollow hold, 2 sets of 20 seconds

Rest about 30 seconds between sets. When it stops being difficult, add time before you add exercises.

Myths vs facts

Myth	Fact
Core exercises burn belly fat	Spot reduction does not work. Abdominal definition tracks total body fat, which responds to diet and overall activity
A strong core means visible abs	Plenty of people with strong, functional cores carry enough body fat that nothing shows. The two are separate outcomes
Longer planks mean a stronger core	Beyond a point you are testing patience. Repeated shorter holds with strict form build more usable endurance
You should pull your belly button to your spine	Hollowing was popular in the 1990s. Current practice favours bracing, tensing the whole wall as if expecting a punch
Sit-ups are the classic core exercise so they must work	They train one movement and involve repeated spinal flexion. Most strength coaches have replaced them
Core training fixes all back pain	It helps many people and is part of standard rehabilitation, but back pain has many causes. Persistent pain needs assessment, not more planks

Frequently asked questions

Can I train my core every day?

You can, because these muscles are endurance-biased and recover fast, but there is little reason to. Three or four focused sessions a week produce the same result with less tedium.

Do squats and deadlifts count as core training?

Heavily. A loaded squat or deadlift demands enormous trunk bracing, which is why lifters often have strong cores without doing dedicated ab work. Carries and rows do the same job.

I get neck pain during core work. What is wrong?

Usually the neck is doing work the abdominals should be doing. In the dead bug and curl-up, keep the head heavy and the chin neutral rather than craning towards the ceiling, and drop the difficulty until the abdominals take the load.

Is the core different after pregnancy?

Yes, and it needs a different starting point. Diastasis recti, a separation of the abdominal wall, is common postnatally and some exercises can make it worse. Start with breathing and pelvic floor work, and see a women's health physiotherapist before planking.

What about the Copenhagen plank?

It is excellent for the obliques and adductors together, and it is also demanding enough to strain a groin if you jump straight in. Begin with the short-lever version, knee resting on the bench rather than the ankle.

How long until I notice a difference?

Most people feel more stable in everyday movements within three or four weeks. Changes to how your midsection looks depend on body fat and take considerably longer.

Disclaimer: This article is general fitness information and not medical advice. If you have back pain, a recent injury, are pregnant or postnatal, or have any condition affected by exercise, check with your GP or a qualified physiotherapist before starting. Stop any exercise that causes pain.