Why Can’t They Just Sit Still?

Understanding Inhibitory Control in Everyday Moments

Picture this.

A child is sitting on a chair… but not quite sitting. They’re leaning back, balancing on two legs.

You say, “Sit properly.”

They stop. For a moment.

Then a few seconds later… they’re doing it again.

It’s Not About “Being Naughty”

From the outside, it can look like:

• not listening

• pushing boundaries

• seeking attention

But what you’re often seeing is something much deeper:

Inhibitory control.

What Is Inhibitory Control?

In simple terms, it’s:

The ability to stop yourself — even when your body or brain wants to keep going.

It’s part of executive functioning, and it affects:

• movement (keeping your body still)

• attention (ignoring distractions)

• behaviour (pausing before acting)

Back to the Chair…

Let’s go back to that moment.

The child knows they shouldn’t lean back. They’ve been told. They understand the rule.

But in that split second:

• their body wants to move

• their brain is seeking stimulation

• the “brake system” doesn’t kick in fast enough

So they lean back again.

Not because they’ve decided to ignore you… but because their brain didn’t stop them in time.

What It Feels Like for the Child

This is the bit many adults don’t see.

For the child, it can feel like:

• their body moves before they think

• they remember the rule after they’ve done it

• they get told off for something they didn’t feel in control of

Why It Happens (Especially in ADHD & Autism)

Children who are ADHD or autistic often have differences in how their brain manages inhibition.

That means:

• their “pause button” is slower

• their need for movement or input is higher

• stopping takes more effort than it does for others

So something as simple as sitting on a chair becomes a constant battle between: “I should stop” vs “my body wants to move.”

What Doesn’t Work

Saying it louder. Repeating it more. Punishing the behaviour.

Because the issue isn’t understanding the rule — it’s being able to act on it in the moment.

What Helps Instead

Think support, not control.

• Give movement before expecting stillness

• Allow alternative seating (wobble cushions, foot rests)

• Use gentle reminders without shame

• Break sitting time into smaller chunks

• Recognise effort, not just success

The Bigger Picture

That child on the chair?

They’re not trying to be difficult. They’re trying to manage a brain that doesn’t always hit the brakes in time.

When we understand that, everything shifts.

From: “Why are they doing that?”

To: “What support do they need in this moment?”