The Respiratory Paradox: How Holding Your Breath Strengthens the Muscles That Breathe

At first glance, breath-holding and breathing training seem like opposites — one stops the breath; the other strengthens it.

But beneath the surface, they share the same biological foundation.

Both train the respiratory muscles, both can reshape the nervous system, and both build a deeper command of the boundary between physiology and will.

What recent science is showing — and what elite freedivers have known for decades — is that breath-holding itself can serve as one of the most powerful forms of respiratory muscle conditioning.

Breath-Holding as Isometric Strength Training

Every long apnea is a war between reflex and restraint.

When ventilation is paused, oxygen lowers, and carbon dioxide rises, the brainstem commands “breathe,” the diaphragm and upper respiratory muscles contracts against a closed glottis — an isometric contraction under hypoxic stress.

It’s the respiratory equivalent of lifting heavy weight without moving the bar.

This repeated internal resistance turns the diaphragm, intercostals, and accessory inspiratory muscles into endurance-trained power fibers.

They work harder than in any resistance-breathing device because they’re fighting the body’s strongest reflex: survival.

This isn’t speculation.

A 2024 MDPI pilot study confirmed that even in beginners, 8 weeks of land-based static apnea (4× per week) improved:

• Max breath-hold +15.8 %,

• Forced vital capacity +12.4 %,

• Minimum heart rate –9.1 %,

• And tolerance to desaturation (SpO₂ –6.8 %).

The key detail: the training was non-immersive and required no device — just breath-holding.

In other words, apnea alone strengthened the respiratory system enough to raise both lung function and autonomic efficiency.

Study: Bezruk D., Bahenský P., Marko D., Kuleshov I., et al. 

The Effect of Static Apnea Diving Training on Physiological Parameters of People with a Sports Orientation and Sedentary Participants: A Pilot Study. 

Sports (Basel) 2024; 12(6): 140.

DOI: 10.3390/sports12060140 | PubMed

The Counterpoint: External Inspiratory Training

A 2025 randomized controlled trial with amateur runners used Inspiratory Muscle Training (IMT) at 50 – 80 % of maximal inspiratory pressure (MIP).

It improved inspiratory and expiratory strength, lowered lactate, and reduced perceived breathlessness — but did not raise VO₂ max.

These results prove that IMT can enhance breathing efficiency and endurance, particularly in people who don’t expose their lungs to true hypoxic challenge.

But when compared with elite breath-holders, the difference becomes striking.

Study: Ren Zhe, Guo Junxia, He Yurong, Luo Yu, Wu Hao. 

Effects of Inspiratory Muscle Training on Respiratory Muscle Strength, Lactate Accumulation and Exercise Tolerance in Amateur Runners: A Randomized Controlled Trial. 

Life 2025; 15(5):705.

DOI: 10.3390/life15050705 | PubMed

The Champion’s Paradox

By contrast, a separate 2024 pilot study examined static apnea training — the same kind used in freediving.

In beginners, the first phase of breath-hold practice often produces a temporary drop in respiratory strength (MIP/MEP). The diaphragm and intercostal muscles fatigue under unaccustomed isometric tension.

But over several weeks, adaptation reverses that pattern. Lung volume and diaphragm endurance increase as CO₂ buffering improves.

One case study of a world‑class freediver within that research showed that even after years of extreme apnea volumes, his inspiratory and expiratory strength never declined. 

His maximal inspiratory and expiratory pressures remained comparable to athletes who had trained with external IMT devices — but without ever using one. 

His breath‑hold training alone preserved and strengthened respiratory performance. These adaptations mirror — and may even surpass — what’s achieved through external IMT devices.

The paradox:

The act of not breathing — when done consciously and progressively — can strengthen the very system built for breathing.

Study: Kuleshov I et al.

The Effect of Static Apnea Diving Training on Physiological Parameters of People with a Sports Orientation and Sedentary Participants: A Pilot Study.

Sports (Basel) 2024; 12(6):140.

DOI 10.3390/sports12060140 | PubMed

Complement, Not Competition

So should you train with an inspiratory trainer? Possibly — especially if you’re not practicing frequent, progressive breath-holds.

IMT can safely build baseline strength for new practitioners or athletes seeking respiratory stability without hypoxia. This is also why I created the BreathBuilt™ eCourse — to train breathing strength and power without external devices. It’s a fully internal method: structured, progressive, and designed to condition the respiratory muscles through effort without equipment.

But for advanced practitioners, BreathHoldWork® already encompasses the same spectrum — and more:

• Mechanical strength through isometric diaphragmatic effort

• Autonomic resilience through parasympathetic dominance under stress

• Cognitive mastery through deliberate composure in the face of reflexive panic

In short, breath-holding isn’t just mental training. It’s also muscular training under neurophysiological load — the purest closed-loop feedback system nature offers.

Final Reflection

Your respiratory muscles don’t care whether resistance comes from a machine or from your own will.

It adapts to tension, resistance, repetition — and meaning.

The difference is that BreathHoldWork® teaches the mind to direct that adaptation — to stay conscious inside the pressure, to convert reflex into control.

A breathing resistance trainer only strengthens the body.

A long, intentional breath-hold strengthens the connection between body and mind.

Erwan Le Corre

Founder of BreathHoldWork®