Learning to swim should be an exciting milestone. For many families though, swim lessons become a source of distress for the child, and for the parents watching on. The child who won’t put their face in the water. The child who panics the moment their feet leave the ground. The adult who has tried repeatedly over the years and still can’t coordinate their arms and legs into anything that resembles swimming.

These children and adults are not being difficult. They are not “drama queens.” They are not lazy or uncoordinated or fearful for no reason.

There is often something deeper going on, something neurological, that no amount of encouraging poolside coaching will fix on its own.

Let’s talk about primitive reflexes.

When a baby is born, they arrive with a set of automatic, involuntary movements built right into their nervous system. These are called primitive reflexes, and they are completely normal and essential in the first months of life. They help the baby survive, turning toward touch, gripping tightly, responding to sudden movement or sound.

As the baby grows and the brain matures, these reflexes are supposed to be integrated. That means the higher centers of the brain take over, and the automatic, survival-driven movements fade into the background. They don’t disappear entirely; they become absorbed into more sophisticated movement patterns.

But sometimes, this doesn’t happen the way it should.

When primitive reflexes remain active beyond the developmental window — we call these retained primitive reflexes — they can interfere with movement, learning, sensory processing, coordination, and emotional regulation in ways that persist right into adulthood.

And the swimming pool? It is, unintentionally, one of the most triggering environments imaginable for someone with retained reflexes.

Let’s unpack what happens in the water.

Just stop and think about what we are actually asking someone to do when we ask them to swim.

We are asking them to:

• voluntarily submerge their face and hold their breath
• keep their legs up and horizontal when every instinct says to drop them down and find the ground
• coordinate their arms and legs in alternating, rhythmic patterns simultaneously
• turn their head to one side to breathe without losing that coordination
• block out the sensation of water in their ears, on their face, up their nose
• manage anxiety, often in a loud, echoey, unpredictable environment

For a nervous system that is already working overtime to manage retained reflexes, this is not just hard. It can feel genuinely unsafe. And that feeling of unsafety is not imagined, it is a physiological response.

So which reflexes are we talking about?

The Moro reflex is one of the most significant. This is the startle reflex, when a baby feels suddenly unsupported or hears a loud sound, they throw their arms wide, gasp, and cry. In infancy it is completely appropriate. When it is retained, the person lives in a near-constant state of low-level alarm. Water touching the face, the sensation of floating, the loss of solid ground under the feet, all of these can trigger a Moro response. The body reads the situation as danger, and floods with cortisol and adrenaline. Learning shuts down. Getting their face in the water is not going to happen, no matter how gentle the teacher is.

The Tonic Labyrinthine Reflex (TLR) influences muscle tone in response to the position of the head. When the head tips forward or backward, it should not significantly affect the rest of the body in a mature nervous system. When the TLR is retained, tilting the head to look down — as you would in breaststroke or freestyle — triggers a whole-body response. The legs drop. The hips sink. The body folds. The child is not kicking incorrectly; their nervous system is responding to where their head is pointing.

The Symmetrical Tonic Neck Reflex (STNR) is closely related. When the head moves up, the arms want to straighten, and the legs want to bend. When the head moves down, the arms want to bend and the legs want to straighten. In swimming, where you need the arms and legs to work somewhat independently of where the head is pointing, a retained STNR makes smooth, coordinated movement feel almost impossible to the learner because for their nervous system, it is.

The Spinal Galant reflex runs along the lower back. Touch or movement along the spine triggers an involuntary hip rotation. You might notice this child is incredibly ticklish along their sides, hates waistbands, or wriggles constantly when seated. In the water, the sensation of water moving around the lower back and hips can trigger this reflex constantly, making it very difficult to keep the body streamlined.

What does this look like at the pool?

It looks like the child who screams at the thought of getting their hair wet, every single lesson for years.

It looks like the adult who can manage in the shallow end but freezes completely when their feet can’t touch the bottom, not because they are irrational, but because the loss of ground contact activates a genuine threat response.

It looks like the child who kicks and kicks, but whose legs just keep sinking, no matter how many times the teacher demonstrates the correct position.

It looks like the person who can do the arm movements standing on dry land, can do the kick while holding the wall, but the moment they try to put it all together, it falls apart completely.

This is not a confidence problem. This is a nervous system problem.

What can help?

The good news is that primitive reflexes can be integrated, even in older children and adults. Specific, repetitive, rhythmic movement activities — often deceptively simple-looking exercises — can help the brain and body work through the developmental stages that were missed, and gradually reduce the interference these reflexes cause.

This takes time, and it takes consistency. But families consistently report that once retained reflexes begin to integrate, progress in swimming (and many other areas of life) often follows.

If your child or someone you care for has been struggling to learn to swim despite repeated lessons, it may well be worth exploring whether retained primitive reflexes are part of the picture. Understanding the “why” is always the first step toward finding the right kind of support.