Cortisol: What It Is, Why It Matters, and How Breathing Helps Regulate It

Cortisol often gets labelled as the “stress hormone” and while that’s not wrong, it’s only half the story. Cortisol isn’t something to eliminate. In fact, without it, performance would suffer. The real issue isn’t cortisol itself, but when it’s switched on, and how well the body can switch it off again.

Understanding this distinction is key to better performance, recovery, and long-term health.

What Exactly Is Cortisol?

Cortisol is a hormone produced by the adrenal glands. Its job is to help the body respond to demands, physical, mental, or emotional.

When cortisol rises, it:

• Increases alertness and focus

• Mobilises energy by releasing glucose into the bloodstream

• Raises heart rate and blood pressure

• Prepares the body for action

This response is essential during moments that require performance: a race, a match, an exam, or a high-pressure presentation. In these situations, cortisol is not harmful, it’s helpful.

Problems arise when cortisol stays elevated for too long.

When Cortisol Becomes a Problem

Cortisol is designed to rise and fall in a natural rhythm. It should peak in the morning to help you wake up, spike briefly during stress or effort, and then return to baseline.

Chronic stress, overtraining, poor sleep, and constant mental pressure can disrupt this rhythm. When cortisol remains elevated for long periods, it can contribute to:

• Poor recovery and fatigue

• Reduced focus and motivation

• Disrupted sleep

• Increased injury risk

• Burnout and anxiety

In other words, performance doesn’t drop because cortisol exists, it drops because the body loses the ability to downshift.

Why Breathing Matters for Cortisol Regulation

Breathing is one of the fastest ways to influence the nervous system. Unlike stretching, supplements, or mindset tools, breathing works in real time.

Slow, controlled breathing stimulates the parasympathetic nervous system, the body’s “rest and recover” mode. This sends a signal of safety to the brain, allowing cortisol levels to fall naturally.

Breathing doesn’t suppress cortisol completely. Instead, it helps the body regain balance after stress or effort.

Breathing for Performance, Not Just Relaxation

This is where breathing is often misunderstood. The goal isn’t to be calm all the time.

The goal is to switch states efficiently.

• Before performance: breathing can sharpen focus and readiness

• After performance: breathing helps accelerate recovery

• Between sessions: breathing resets baseline stress levels

When practiced consistently, breathing trains the body to handle stress better,

not avoid it.

The Takeaway

Cortisol isn’t the enemy. It’s a vital performance hormone. What matters most is your ability to regulate the stress response and recover effectively.

Breathing is one of the simplest and most powerful tools to do exactly that, no equipment, no guesswork, just physiology.

At Breathing Buddy®, we focus on training breathing the same way athletes train strength or endurance: with intention, structure, and performance in mind.