How to Properly Engage Your Core While Walking

Your core muscles already switch on automatically every time you take a step. The real challenge is not learning to activate something that was dormant but supporting the natural pattern your body uses, at the right intensity, without overdoing it or letting poor posture undermine it. Research shows that the deep trunk muscles stay tonically active throughout most of the walking stride, while the more superficial layers pulse on and off to manage rotational forces and weight shifts. Getting this right matters more than most people realize, and the common advice to “just suck in your belly” turns out to be the wrong cue entirely.

What Your Core Actually Does During Walking

Walking looks simple from the outside, but your trunk is quietly managing a complex balancing act with every stride. The lateral abdominal muscles, including the internal oblique, external oblique, and transversus abdominis, are active during at least three-quarters of the stride cycle, serving a continuous stabilizing function rather than firing in brief bursts.¹ Each of these muscles has a slightly different timing pattern. The transversus abdominis tends to be more active when the leg on the same side swings forward, while the external oblique ramps up when the opposite leg swings. The internal oblique stays relatively even throughout.

Deeper in the back, the multifidus muscle shows a similar split. Its deeper fibers maintain a prolonged, almost constant level of activation during walking, functioning like a postural brace for the lumbar spine.² The superficial fibers of that same muscle, by contrast, cycle on and off more rhythmically to help control trunk rotation. This division of labor means the “core” is not one thing doing one job. It is a layered system where deeper muscles hold steady tension and outer muscles adjust dynamically.

As you walk faster, the overall amplitude of trunk muscle activation rises, but the basic timing pattern stays roughly the same between a slow stroll and a brisk pace.³ The back muscles, in particular, hold a fairly consistent baseline level even as speed increases from a leisurely walk to a fast one. Your body modulates intensity more than it changes strategy, which is why good posture habits at a slow pace tend to carry over when you pick up the tempo.

Bracing Beats Hollowing

If you have ever been told to “pull your belly button toward your spine” while walking, you have been given the hollowing cue. It specifically targets the transversus abdominis and was popularized by physical therapists in the 1990s. The competing approach, bracing, involves gently stiffening the entire abdominal wall as if you were about to be lightly poked in the stomach. It co-contracts multiple muscles at once rather than isolating one.

A biomechanical simulation study comparing the two strategies found that bracing improved lumbar stability by about 32 percent, with a modest 15 percent rise in spinal compression. The transversus abdominis in isolation, the muscle targeted by hollowing, contributed less than one percent of that stability gain.⁴ The researchers concluded that there is no clear mechanical rationale for using an abdominal hollow to enhance spinal stability, and that bracing creates patterns that work better for protection during movement.

In practical terms, this means you do not need to think about one specific muscle when you walk. A light, broad stiffening of your midsection, the kind that happens naturally if you imagine someone is about to tap your stomach, does a better job than trying to suck your navel inward. The bracing cue also has the advantage of being easier to maintain. Hollowing can interfere with breathing and feels unnatural once you try to sustain it over a long walk.

Breathing and Pressure Work Together

One common worry is that engaging your core will make it hard to breathe normally. In reality, the diaphragm and the transversus abdominis are designed to work as a team. During movement, both stay tonically active while also cycling through the breathing rhythm, and the result is a sustained rise in intra-abdominal pressure that scales with how forceful the movement is.⁵ Inhalation and exhalation are managed by opposing adjustments between the diaphragm pushing down and the abdominal muscles pushing inward, varying the shape of the pressurized abdominal cavity without losing the stabilizing pressure.

The takeaway for walking is simple: you should be able to hold a conversation while maintaining a gentle brace. If you are clenching so hard that your breath feels shallow or forced, you have overshot the target. A useful check is to hum or count out loud. If the sound stays smooth and steady, your breathing pattern is accommodating the brace without trouble. If it comes out strained or choppy, dial the tension down.

The Over-Engagement Trap

More is not better. People with chronic low back pain often develop what clinicians call a guarding mechanism, where the trunk muscles stiffen excessively during walking. This trunk stiffness leads to abnormal movement patterns in the spine, reducing the natural small rotations and lateral shifts that make gait efficient.⁶ In effect, the body tries to protect a painful area by locking everything down, but that rigidity backfires by increasing energy cost and shifting loads to joints that are not built to handle them.

This pattern is not limited to people in pain. Anyone who walks around with their abs maximally clenched, sometimes because a well-meaning trainer told them to “keep their core tight at all times,” risks mimicking the same guarding response. The spine needs a degree of controlled movement during walking. Your pelvis tilts, your thorax rotates slightly in the opposite direction, and the segments of your lumbar spine flex and extend a few degrees with each stride. Locking that motion down with excessive bracing removes the shock absorption your spine relies on and can leave you feeling more fatigued, not less.

A good mental model is a dimmer switch, not an on-off toggle. You want enough tension to feel that your midsection is firm and supportive, but not so much that your torso becomes a rigid block. For most everyday walking, think of engaging at roughly 20 to 30 percent of your maximum contraction.

Simple Cues That Actually Work

Verbal and mental cues can make a real difference in muscle recruitment. Research on gluteal activation found that verbal cues alone increased gluteus maximus force production by about 13 percent compared to performing the same movement without a cue.⁷ That study was looking at a different movement, but the principle transfers: telling yourself something specific about what to do changes how your muscles fire.

Here are cues that tend to work well for core engagement during walking:

Grow tall: Imagine a string pulling the crown of your head toward the sky. This lengthens the spine and naturally activates the deep postural muscles without requiring you to think about individual abs.
Brace for a tap: Lightly stiffen your midsection as if someone were about to poke you just below the ribs. Hold that at a low level and keep breathing normally.
Ribs over hips: Picture stacking your ribcage directly above your pelvis. This prevents the common posture of flaring the ribs forward, which disengages the obliques and shifts load onto the lower back.

Tactile feedback can help too. Placing your hands briefly on your lower abdomen while walking lets you feel whether the muscles are lightly firm or completely relaxed. Once you recognize the sensation, you can reproduce it without your hands. Some people find that wearing a snug (not tight) waistband provides a similar passive reminder.

How Arm Swing Supports Your Trunk

Arm swing is not decoration. Your swinging arms counteract the rotational forces produced by your swinging legs, preventing your trunk from twisting excessively with each step.⁸ In normal walking, the thorax rotates slightly opposite to the pelvis, and the arms amplify that counter-rotation to keep things balanced. In race walking, thorax rotation roughly doubles compared to normal walking, and the pelvis rotates through a larger range as well, creating significant torsional forces through the trunk.

If you walk with your hands in your pockets or holding a phone in front of your face with both hands, you remove this natural counter-rotation system. Your core muscles then have to work harder to control the twist, which can feel tiring over long distances and may contribute to lower back fatigue. Letting your arms swing freely, with a relaxed bend at the elbow, is one of the easiest things you can do to support your core without consciously engaging anything.

Walking With a Backpack or Load

Carrying a load changes the equation. You might expect that strapping on a heavy backpack would make your back muscles work harder, but the research is more nuanced. One study found that wearing a backpack actually reduced activation in the erector spinae and multifidus muscles and restricted spinal range of motion in both lateral bending and axial rotation.⁹ The body appears to stiffen the trunk passively to manage the external weight, reducing the need for active muscular contraction but also reducing healthy spinal movement. Hip rotation increased to compensate, suggesting the load shifted mobility demands downward in the body.

How you carry the load matters too. Using a hip belt to transfer weight from the shoulders to the pelvis reduced rectus abdominis activity compared to carrying the same pack on the shoulders alone, while the external obliques were not affected by the belt one way or another.¹⁰ Interestingly, the deeper back muscle longissimus was less active during both backpack conditions compared to walking without a pack, while a neighboring muscle, the iliocostalis, did not change. These muscles run nearly parallel along the back but appear to be under different motor control strategies depending on whether the load demands stability in the front-to-back plane versus the side-to-side plane.

If you regularly walk with a loaded pack, the practical advice is to use a hip belt, keep the load centered and close to your body, and periodically check that you have not locked your trunk into a rigid block. A brief pause to stretch your spine through some gentle rotation can help restore the natural movement your body sacrifices under load.

What Hills Do to Your Trunk Muscles

Walking uphill places dramatically higher demands on the back extensors. A study of soldiers walking with loads at various gradients found that erector spinae activity increased by up to about 250 percent during uphill walking compared to flat ground.¹¹ The combination of heavy load and steep incline pushed both muscle activity and stress hormone levels to their highest recorded values in the study.

For recreational walkers, this means that your core is already getting a significant training stimulus on hilly terrain, even without any conscious effort to engage. If you are working on building core endurance for walking, incorporating hills or incline treadmill sessions is one of the most effective strategies available. Conversely, if you have a back condition that flares with heavy spinal loading, be aware that steep uphills demand considerably more from your back than flat walking does and may need to be introduced gradually.

Age-Related Shifts in Core Activation

As people age, the automatic activation of trunk muscles during walking tends to decline. A study comparing younger and older women found that older women had roughly 52 percent lower internal oblique activation during the initial stance phase of walking.¹² The quadriceps showed a similar drop of about 40 percent. Researchers attributed this to age-related weakness and balance impairments, and it helps explain why older adults sometimes develop a shuffling or cautious gait pattern.

This decline is not inevitable, though. Targeted core and hip strengthening can offset the losses. Research on pelvic stability training in stroke patients, who face an exaggerated version of the same trunk weakness that aging produces, found that pelvic stability exercises improved hip muscle strength across all directions, improved trunk control, and increased walking speed compared to standard physiotherapy alone.¹³ The gains were statistically significant and spanned flexors, extensors, abductors, and adductors of the hip. While stroke recovery is a different context, the underlying principle is broadly relevant: strengthening the muscles around the pelvis translates directly into better walking.

Core Endurance Matters More Than Peak Strength

When it comes to walking capacity, the ability to sustain moderate trunk muscle activity over time appears more important than how hard you can contract at maximum effort. A study of patients with multiple sclerosis found that hip extension strength, the Sorensen test (a timed back extension hold), and the lateral bridge test together explained more than half the variability in timed walking tests and around 60 percent of variability in a two-minute walk test.¹⁴ Core endurance and hip strength were the strongest predictors, not peak abdominal force.

For anyone building a walking routine, this suggests that planks, side planks, and bird-dogs, exercises that train the core to hold moderate contractions for extended periods, are more relevant than crunches or heavy cable rotations. The goal is to build the endurance your trunk needs to maintain posture over a 30- or 60-minute walk, not to generate short bursts of abdominal power.

Core Training Combined With Walking for Back Pain

If you are walking partly to manage low back pain, adding dedicated core stabilization exercises appears to amplify the benefit. A six-week trial compared core stabilization exercises alone, core stabilization exercises combined with 30 minutes of walking, and a control group in people with nonspecific chronic low back pain. Both exercise groups saw significant reductions in pain and disability, but the combined group, the one that paired core work with walking, showed the greatest improvement in disability scores.¹⁵ The difference between the two exercise groups did not reach statistical significance, so the combined program was not dramatically better, but the trend favored pairing the two rather than doing core work alone.

The likely reason is that core stabilization exercises teach you how to activate the right muscles at the right intensity, and walking then gives you a prolonged, real-world context in which to practice that activation. The walk becomes a kind of extended rehearsal for the motor patterns you build during the exercises.

What Your Shoes Are Doing to Your Core

Footwear choices affect trunk muscle activation more than most people suspect. A study of people with chronic low back pain compared trunk muscle activity while walking in flat-soled shoes versus unstable rocker-bottom shoes. The unstable shoes produced significantly higher activation in the erector spinae, the rectus abdominis, and the internal oblique compared to the flat shoes, with the erector spinae showing a large effect size.¹⁶ The instability underfoot forced the trunk muscles to work harder to maintain balance.

This does not necessarily mean unstable shoes are the right choice for everyone. For someone recovering from back pain, the extra trunk demand could be therapeutic or it could be aggravating, depending on the person’s current capacity. For someone who already has good core activation patterns, walking on a slightly unstable surface (grass, a sandy beach, a trail with uneven footing) can provide a similar stimulus without specialized footwear. The key point is that the surface under your feet is a variable worth paying attention to when thinking about core engagement during walking.

When Ankle Problems Change Core Strategy

Injuries far from the trunk can alter how the core behaves during walking. People with chronic ankle instability show increased rectus abdominis and erector spinae activation both before and after heel contact compared to people with healthy ankles.¹⁷ At the same time, the hip and thigh muscles (gluteus medius, rectus femoris, biceps femoris) showed reduced activation. The body appears to compensate for an unreliable ankle by stiffening the trunk and reducing reliance on the hip stabilizers, a tradeoff that protects the ankle but loads the spine more heavily.

If you have a history of ankle sprains and find that your lower back gets tired during long walks, this compensation pattern may be part of the reason. Addressing the ankle instability through balance training and strengthening can gradually allow the hip muscles to take back their share of the stabilization work, reducing the excessive demand on your core. The body treats the whole chain as connected, and a problem at the bottom changes strategy all the way up.