Which muscles are included in the core?

Rectus abdominis, the external and internal oblique muscles, transversus abdominis, erector spinae and multifidus — muscles around the abdomen, lower back and pelvis that contribute to control and stability.

Does a lifting belt do the work for you?

No. A belt can make it easier to maintain good abdominal pressure by giving the abdominal muscles something to tense against, but it does not create the abdominal pressure for you.

Do you need direct core training if you already squat and deadlift?

Squats, deadlifts, standing presses and other free weight exercises already train the core muscles, but direct training can still be useful if the goal is to get stronger in the compound exercises.

How many core exercises should you do, and when?

Two to three exercises a couple of times a week, added towards the end of the strength workout after the heaviest compound exercises.

Why are sit-ups not enough?

Sit-ups primarily train the abdominal muscles by bending the upper body, while heavy lifts also require the muscles to resist movement in various directions — anti-extension, anti-lateral flexion and anti-rotation.

Why the Core Muscles Are Important When Lifting Heavy | Hardworkout Magazine

Key takeaways

- The core muscles stabilise the pelvis and spine so that the force generated by the legs can be used in squats and deadlifts.

- Resisting movement matters more than creating movement when the core is working under a heavy barbell.

- Intra-abdominal pressure is built before the lift starts by taking a deep breath and bracing the abdominal muscles, and is held throughout the repetition.

- A lifting belt does not create abdominal pressure; it gives the abdominal muscles something to brace against.

- Two to three direct core exercises a couple of times a week, placed after the heaviest compound lifts, is enough if they are progressed over time.

In squats, deadlifts, and standing presses, it is not just the legs, back, and shoulders that determine how heavy you can lift. The core muscles also have an important role when the weights get heavy.

To understand why, we need to look at which muscles are involved, what they do during heavy compound exercises, and how they can be trained to become stronger.

How to strengthen your core for heavy lifts

Which muscles actually make up the core?

The core muscles consist of several muscles around the abdomen, lower back, and pelvis that contribute to control and stability.

In squats, the core muscles stabilize the pelvis and spine while the legs generate force.

During deadlifts, the muscles around the abdomen and back help keep the upper body stable while the barbell is lifted.

In standing shoulder presses, the core muscles prevent the pelvis from tipping forward and the arch in the lower back from increasing.

A good abdominal pressure makes the upper body stiffer and is particularly important when lifting heavy weights.

Squats, deadlifts, and other free weight exercises train the core muscles while larger muscle groups are also being worked.

Planks, ab wheel, side planks, Pallof press, and farmer’s walk train the core muscles in different ways.

Direct core training can be done after the compound exercises and should have gradual progression in weight, repetitions, or range of motion.

The muscles around the abdomen and back

The core muscles consist of several muscles around the abdomen, lower back, and pelvis.

- Rectus abdominis (the straight abdominal muscle): Located at the front of the abdomen and contributes, among other things, to bending the upper body and counteracting arching in the lower back.

- Obliquus externus and internus (external and internal oblique muscles): Located on the sides of the abdomen and contribute to rotation and lateral bending, but also to resisting these movements.

- Transversus abdominis (the transverse abdominal muscle): Lies deeper than the other abdominal muscles and wraps around large parts of the abdominal cavity. It helps stabilize the spine and pelvis.

- Erector spinae (the back extensors): Located along the spine and help extend the back and counteract forward bending of the upper body.

- Multifidus: Consists of small, deep muscles along the spine that help control and stabilize the individual parts of the spine.

Thus, the core muscles can both create movement and resist movement in the upper body. The latter function is particularly important when you need to keep the body stable during heavy lifts.

![Core Muscles](https://hardworkout.no/wp-content/uploads/2026/08/ChatGPT-Image-28.-aug.-2026-101915-e1787905226799.png)

Why does core stability decide how much you can lift?

In squats, the quadriceps and glute muscles are important when you rise from the bottom position. The hamstrings also contribute to control around the hip and knee.

At the same time, the muscles around the abdomen and lower back must stabilize the pelvis and spine. If the upper body falls too far forward, it becomes more difficult to utilize the power from the legs.

In deadlifts, particularly the glute muscles, hamstrings, and quadriceps contribute when the hips and knees extend. The back extensors and abdominal muscles keep the upper body stable while the barbell is lifted.

In standing shoulder presses, the abdomen and lower back must prevent the pelvis from tipping forward and the arch in the lower back from increasing.

Abdominal pressure during heavy lifts

During heavy lifts, good abdominal pressure helps make the upper body stiffer.

How do you build intra-abdominal pressure before a heavy lift?

Before the lift, you take a deep breath and tense the muscles around the abdomen. The diaphragm moves downward, while the abdominal muscles and pelvic floor help increase the pressure in the abdominal cavity.

For heavy squats and deadlifts, you create the abdominal pressure before the movement starts and maintain the tension throughout the lift. Afterwards, you can exhale and inhale again before the next lift.

Does a lifting belt create the abdominal pressure for you?

A lifting belt can make it easier to maintain good abdominal pressure by having the abdominal muscles tense against the belt. The belt does not create the abdominal pressure for you.

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![Image](https://hardworkout.no/wp-content/uploads/2018/10/AdobeStock188958662-1024x683.jpeg)

Health and lifestyle Eccentric strength training: Why you should lower the weights more slowly

Aug 28, 2026

Train the core muscles effectively

Squats, deadlifts, standing presses, and other exercises with free weights already train the core muscles. Direct training can still be useful if the goal is to get stronger in the compound exercises.

Which exercises train the core for heavy lifting?

Sit-ups primarily train the abdominal muscles by bending the upper body. During heavy lifts, the muscles must also be able to resist movement in various directions. This can be trained with exercises that place different demands on the core muscles:

- Counteracting arching in the lower back: Plank, dead bug, and ab wheel train the ability to keep the pelvis and lower back stable.

- Resisting lateral bending: Side plank and suitcase carry train the muscles on the side of the abdomen to keep the upper body stable.

- Resisting rotation: Pallof press trains the ability to prevent the upper body from rotating.

- Stability with heavy weight: Farmer’s walk trains strength and endurance in the abdomen and back while walking with heavy weights.

How much direct core training do you need?

You do not need many specific exercises. 2-3 exercises a couple of times a week can be added towards the end of the strength workout, after the heaviest compound exercises.

This training should also have progression. Increase the weight or number of repetitions as you get stronger. In exercises like the ab wheel, you can gradually increase the range of motion.

![training trends core muscles](https://hardworkout.no/wp-content/uploads/2020/03/AdobeStock196207735-scaled.jpeg)

Sources:

Core training and performance: a systematic review with meta-analysis – [Biology of Sport](https://www.termedia.pl/Core-training-and-performance-a-systematic-review-with-meta-analysis,78,49398,1,1.html)

Core Muscle Activity during Physical Fitness Exercises: A Systematic Review – [International Journal of Environmental Research and Public Health](https://www.mdpi.com/1660-4601/17/12/4306)