Heart coherence: the most underrated tool of the modern founder

During my first week of mental performance training, my instructor asked me something seemingly simple: practice heart coherence every day, for 8 weeks.

Honestly, I had my doubts.

5 minutes of breathing, was that really going to change anything for me, at my level of daily pressure?

8 weeks later, I have to admit something: this tool is probably the most underrated tool of the modern founder.

Not because it is miraculous. But because it acts where no productivity tool can reach: on your nervous system.

And as long as your nervous system is on permanent alert, no leadership, strategy or organization tool will hold.

Here is why.

Your nervous system is in survival mode 24/7

When you live under continuous pressure, your body does not take breaks. It stays constantly activated.

Concretely:

• your body releases cortisol (the stress hormone) around the clock
• your heart rhythm becomes erratic
• your brain prioritizes immediate survival, not strategic thinking
• your perception narrows

You make decisions under tension.
You ruminate instead of deciding.
You react instead of responding.

And it is not a matter of weakness. It is physiological.

You cannot think clearly when your body is on alert.

It is exactly what our instructor Guillaume Rivas repeats at every session: "The body is the gateway to the mind."

As long as you do not act on your body, mental work will go right over your head.

What heart coherence really is

To be clear, heart coherence is not a relaxation technique. It is not a "wellness moment" you allow yourself to decompress.

It is a calibrated physiological protocol, validated by research for more than 20 years, that synchronizes your heart rhythm with your breathing to activate the parasympathetic system: the "recovery" branch of your nervous system.

The principle is simple:

• 6 breaths per minute
• 5 seconds inhaling
• 5 seconds exhaling
• For 5 minutes
• 3 times a day

This is the 365 method: 3 x 5 minutes, at 6 breaths per minute.

That is it.

No equipment.
No complicated posture.
No mandatory app, although an app can help at the start to hold the rhythm. I built Resonance precisely for that: an app dedicated to heart coherence and guided breathing, with a simple visual guide.

And yet, within a few weeks of practice, the effects are measurable:

• lower cortisol
• higher heart rate variability (a key marker of nervous system health)
• activation of the vagus nerve
• better mental clarity and sleep quality

It is one of the very few practices with a measurable physiological effect in under 10 minutes.

Why it resonates with founders

Elite athletes have been using this kind of protocol for 30+ years.

Most founders, on the other hand, discover heart coherence the day something starts to crack. And by then, it is often too late.

Yet it is precisely the tool they need most before things crack.

If you are stacking up:

• important decisions every week
• high-stakes meetings
• unpredictable pressure spikes
• days when you never truly switch off

Then your nervous system is running in permanent sympathetic mode.

That is exactly what heart coherence corrects.

It does not remove the pressure, but it teaches your body to return to calm faster, so that you become capable again of thinking, deciding and acting with more lucidity.

How to integrate it concretely

You do not need to overhaul your life for it to work.

Here is a progressive 3-step approach.

Step 1: Observe what is happening in your body

Before practicing, observe.

For one week, notice the moments when your body is under tension:

• waking up with a racing heart
• meetings where your shoulders tighten
• evenings when you cannot "come back down"

Putting words on these moments is already the beginning of taking back control.

Step 2: Install the base

Start with one single session per day, in the morning upon waking or within the following 30 minutes.

5 minutes. 6 breaths per minute. That is all.

The goal is not performance. It is regularity.

Better 5 minutes a day for 3 weeks than 20 minutes once.

Step 3: Use coherence in real situations

Once the base is installed, you can start using it as a real-time regulation tool:

• before a high-stakes meeting: 5 minutes to arrive clear
• after a difficult call: 5 minutes so you do not carry it into the next one
• before going home: 5 minutes so you do not bring the tension home

In sports, these are called transition rituals.

What happens between the important moments determines the quality of the important moments.

The same is true for a founder.

The real promise

Heart coherence will not turn you into a zen founder.
It will not erase the pressure.
It will not replace deep work on your identity, your mind, your vision... in reality, its true promise lies elsewhere.

It gives you, in 5 minutes, a return-to-calm button you can press whenever you need it.

Not to escape the pressure, but to stop being at its mercy. To become capable again, within minutes, of thinking clearly, deciding right, and responding instead of reacting.

And in a founder's life, this simple lever changes a lot of things.

Many look for complex solutions to take back control.

Sometimes, the first brick is simpler than you think.

If you want to dig into the physiology, the exact protocol and the use cases of this tool, I built a complete guide here.

Enjoyed this letter?

In upcoming editions, I will go deeper into the protocols athletes have been using for 30 years, and that have barely crossed the doors of the business world.

If you have not already, do not forget to subscribe.

Thibault