Beginner’s Guide to Switching from Mouth to Nose Breathing

Written by someone who trains, breathes, and recovers like you do.

Let’s be real…

If you’re like I used to be, you probably breathe through your mouth when you train.
Sprint intervals, heavy lifts, even rushing for the train, my mouth was wide open like I was trying to inhale the whole atmosphere.

I didn’t think it mattered… until I started digging into nasal breathing and read Breath by James Nestor. His bestselling exploration shows how chronic mouth breathing undermines health and performance, while nasal breathing restores balance, endurance, and recovery.

Here’s how to switch to nasal breathing without feeling like you’re suffocating on your first try.

Why Nasal Breathing Improves Endurance and Recovery

Your nose isn’t just a decoration, it’s your built-in, high-performance breathing tool. Compared to mouth breathing, nasal breathing provides:

• Better oxygen delivery → Breathing through the nose produces nitric oxide, which widens blood vessels and improves oxygen transfer to muscles. Nestor notes a sixfold increase in nitric oxide and up to 18% more oxygen uptake when breathing nasally.
  

• Improved endurance → You breathe slower, retain more CO₂ (a performance advantage), and train your body to use oxygen more efficiently.
  

• Reduced dehydration → Mouth breathing dries you out, causing “dry mouth death” and disrupting sleep quality.
  

• Calm under pressure → Nasal breathing activates the parasympathetic nervous system, lowering stress and keeping your heart rate under control in workouts, races, or even high-stress office days.
  

• Science-backed gains → Research shows nasal breathing can increase nitric oxide levels by up to 25%, directly supporting endurance and recovery.
  
  

What to Expect When You First Switch

Truth? It’s going to feel strange.

Your brain is used to gulping huge amounts of air through your mouth, so your first nasal-only workout may leave you feeling “air hungry.”

This isn’t lack of oxygen, it’s low CO₂ tolerance. With practice, your body adapts. After a few weeks, you’ll notice slower, steadier breathing, calmer focus, and more gas in the tank at the end of a session.

(Nestor’s experiments showed that even a few weeks of consistent nasal breathing improved sleep, recovery, and focus dramatically.)

How to Switch to Nasal Breathing Without Struggle

Step 1: Start at Rest

At your desk, walking, or commuting, keep your mouth closed. Inhale slowly through the nose, exhale through the nose. Feel your belly rise. Build awareness without pressure.

Step 2: Take It Into Easy Training

During recovery runs, warm-ups, or zone 2 rides, stay nasal. If you feel like gasping, slow your pace, not your progress. You’re training your breathing system like a muscle.

Step 3: Reinforce It at Night

Nighttime is when habits stick. A simple strip of BREEV Mouth Tape trains you to breathe nasally during sleep, boosting recovery and deep rest. I tape every night, game changer.

Step 4: Level up with breath drills

Here are my go-to’s:

Staying conscious of nasal breathing during every session is key, and BREEV Nasal Strips support this by keeping the airways open and oxygen flow steady.

The Payoff

Before nasal breathing, I’d finish long runs wrecked: dry mouth, pounding heart, legs that took days to recover.

Since switching:

• Recovery is faster
  

• Splits are steadier
  

• HRV is higher
  

• Sleep is deeper
  
  

It’s not just for running. My lifting is more controlled, my sparring calmer, and even stressful days don’t knock me down.

Final Word

You don’t need to overhaul your training plan.

Just start closing your mouth more often: in warm-ups, on easy runs, even at your desk.

Support your training with BREEV Mouth Tape at night and BREEV Nasal Strips during the day or in high-intensity sessions. Within weeks, you’ll notice the difference.

Your lungs, your legs, and your recovery will thank you.