Struggling With a Swimming Performance Plateau?

Stephanie is a friend who came to me knowing that I’ve been immersed in the world of breath for years. She is an accomplished open water and pool swimmer. She can hold 100s on a 1:10 interval and recently won the Portland Bridge swim, a grueling 10-mile open water swim in Portland, Oregon’s Willamette River. She sat in front of me in August 2021 reporting a loss of efficiency in the water and shortness of breath that seemed out of proportion for her activity. She was working harder, and resting better than ever, but felt her performance did not match her training efforts. Many of us struggle with breathing, without even realizing it. What you might not realize is that while most of us could use better access to oxygen, breathing more is not the way to get it.

The Problem We Don’t Know We Have

Stephanie fell into what happens to a lot of swimmers. I’ve been there myself. Resting breathing can become disrupted from the downside of chronically trying to perform better, keeping up, staying ahead, and striving. Breathing well or breathing poorly starts and ends in the mind.  How we feel drives how we breathe, and how we breathe further drives how we feel. When we chronically sacrifice form, feel, and enjoyment in the water for a desired performance, we run the risk of disrupting healthy breathing patterns. It’s wild.  Poor breathing patterns include

  • fast breathing, & larger volumed breaths than needed (over breathing)
  • frequent spontaneous breath-holds
  • chest breathing
  • mouth breathing  

Poor breathing patterns challenge the feel-good parts of our nervous system. We can get stuck in a downward cycle of poor breathing patterns without realizing it. Add the fact that swimming facilitates upper chest and mouth breathing – further undermining good breathing and negatively impacting our nervous system [4-11]. Now you have a perfect recipe for breathing dysfunction that eventually drops the ceiling on performance.   If we understand how to leverage the breath for health and performance, we can manage chronic-striving (always trying to be and do better) and train strong breathing practices that ultimately improve performance – without training harder.

How Stephanie Got Ahead

Stephanie embarked on a 6-week tailored Breathe Your Truth program to help restore balanced breathing.

  • She committed to staying in nose breathing while recovering at the wall between swims – and adjusted her training intensity to allow for the adaptive changes in her nasal passages that come with nose breathing during training.
  • She stayed aware of her breathing pattern while swimming – which naturally slowed it down.
  • She did pull-sets in which she alternated by 50s, a comfortable breathing pattern with a slight to moderately uncomfortable breathing pattern.
  • Lastly, she practiced no-breather 25s as her last workout set – at a pace that was not too slow or two fast to maintain the breath hold. We call these Zen 25’s because they help the body become efficient, alert, and relaxed in the presence of elevated carbon dioxide.

 After 6 weeks, Stephanie progressed from a breathing pattern of 2-3 freestyle strokes per breath to being comfortable with 5-7 strokes per breath for most of her workout. Her baseline, or resting CO2 improved from below normal to above normal levels (this is a good thing – more on that soon). Her tolerance to nose breathing improved from moderate intensity to heavy intensity exercise.  Most importantly she felt stronger in the water and her shortness of breath went away.

11 months later, Stephanie still reports feeling strong in the water. She has settled on doing one challenge breathing set a week, and for the rest she simply maintains good breathing hygiene. This includes nose breathing during all dry land exercise, nose breathing at the walls during a swim workout, and frequently comfortably slowing her breath while engaged in daily activities.

How is it That Breathing Less Improves Performance?

The Surprising Physiology That Explains It All

The answer is rooted in basic respiratory physiology – but it is rarely applied.  We breathe in oxygen (O2) and we breathe out carbon dioxide (CO2). While CO2 has a bad reputation for being a waste product, it turns out that itis very important.  CO2 is needed in the blood to help oxygen get out of the blood and into cells. If CO2 is too low, as in the case of breathing too much, O2 gets trapped in the blood. While there may be plenty of oxygen in the blood, the body cells may struggle to access it [12-14].  When we chronically breathe too much (too fast and too big), we lower the set point for CO2 and the body creates a new-normal. In this case, the new-normal of low CO2 makes it hard for the oxygen carrying red blood cells to release oxygen in the body where it’s needed. Chronic over breathing has become extremely prevalent  [1-3, 15, 16].  As poor breathing is learned, it can also be unlearned. By strategically exposing the body to slightly higher training CO2 levels from breathing less, we retrain the set-point of CO2 to a higher level, a better normal. This changes the acid-base balance of blood in a way that makes oxygen more available [17]. The body functions with more ease, and with more reserves for physical and mental performance.

The Answer to Getting More Oxygen

The answer to improved swim-training is not to breathe more but to actually breathe less – and consequently get more (oxygen). Done correctly, beathing less changes resting acid-base blood balance toward better rest and performance.  Don’t be surprised if this does not feel comfortable at first. It turns out that CO2 is the primary driver for breathing – not oxygen [12, 18-21]. 

As CO2 levels climb, the body signals a need for more air (even if oxygen levels are okay). The game you’ll play is to sit (swim) in the face of this urge to breathe more, with confidence that your brain is simply sending a conditioned message, and you’re just fine. Give yourself time to adjust. Be patient and know that small changes are better than heroic efforts. In fact, heroic efforts to hold the breath will antagonize the system and are more likely to set you backwards – if not hurt you.

Ten Effective Ways to Raise CO2

It is important to modify the intensity of your training to accommodate the practice.

  1. Pay attention to your breathing while swimming freestyle. Just the act of paying attention will slow breathing. You may even feel comfortable adding a stroke or two before your next breath. Do this for at least one set each workout. Make this is the most important thing you do.
  2. Kick with your face in the water, or bring intention to the breath while on your back.
  3. Hum the exhale while swimming.
  4. Nose breathe at the wall between sets.
  5. Pace breathing during backstroke – breathe in on one arm, breath out on the same arm, repeat.
  6. Do pull sets with breath regulation, alternating by 50s with base breathing pattern and a challenge pattern. For example, alternating breathing every 5th and 7th stroke by 50s.
  7. Swim sets where the focus is to not breathe in or out of the turns – breathing as desired between the flags
  8. 25 yard no- breathers done for stroke efficiency on a comfortable interval.
  9. 15 yard no-breathers done at the end of an exhale, at maximum speed and a tight interval [22].
  10. End workouts with a 2-5 minute meditation while still in the water. Feel the water pressure guide breathing with the diaphragm. Connect to any feelings of contentment, satisfaction, joy in your nervous system. They’re there – just listen for them. 🙂

You may have noticed that the activities are listed by increasing difficulty – except for the last one. Not all activities are appropriate for everyone. Your best gains will come from matching the work to your current breathing ability. Patience, lightness, and enjoyment win the day. We use 5 breathing tests that you can do yourself – to identify your best breath work activities. Find these tests, along with sample workouts at Breathe Your Truth SwimTrue.

Reach out for a FREE 30 minute consultation to increase your performance.

David Deppeler, PT, DSc, is the founder of Breathe Your Truth, a project dedicated to helping people breathe better for health and performance. He lives in Cocoa Beach, Florida and works with anyone looking to improve  their breath-body (mind) relationship. The work can be done in-person or remotely online. He swims with Swim Melbourne Masters, in Melbourne, Florida.




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