Articles from York Biofeedback

Biofeedback, neurofeedback, biohacking & stress management

Glyn Blackett □ Stress Management & Biohacking Coach

Optimize Brain Oxygen Delivery with Capnometry Biofeedback

Capnometry or Capnography Biofeedback For Optimal Brain Performance

Biofeedback is a tool for setting up the physiological conditions that support emotional wellbeing, energy, focus, motivation and clear thinking - in other words, for optimal brain performance. How does it do that? By measuring and feeding back data relating to brain function, as a basis for learning self-regulation skills. To understand this more fully, we need to take a closer look at what we can measure and how it relates to brain peformance. In this article, we're going to take a look at capnometry, also known as capnography, which measures carbon dioxide in exhaled air. This tells us to what extent you may be over-breathing.

Why Over-breathing Matters

Over-breathing, also known as hyperventilation, matters because it significantly impairs brain performance. It paradoxically reduces oxygen delivery to brain cells. Later I'll explain how.

Symptoms of Over-Breathing (Hyperventilation) occur at different levels:

  • physical - laboured breath, chest pains, fatigue, nausea, headaches
  • mental - poor concentration, fuzzy-headedness, impulsiveness
  • emotional - anxiety and panic, depression, emotional volatility.

You've probably heard of hyperventilation in the context of panic attacks. A panic attack would involve quite an extreme degree of over-breathing - perhaps reducing the oxygen supply to the brain by as much as 60 %. But that's just the tip of the ice-berg. Here's the important point: low-level over-breathing is both common and largely unrecognized. It might involve a 10 to 20% reduction in oxygen delivery - significant, but chances are you wouldn't recognize it as hyperventilation. So if you think you don't over-breathe, you might want to think again.

How Over-Breathing Impairs Brain Performance

When you over-breathe you reduce the level of carbon dioxide dissolved in your blood. That might not sound important given that carbon dioxide is a waste product - but actually it has important functions in the blood. For example it controls blood pH or acidity.

When blood CO2 is reduced, the blood holds on more tightly to its oxygen, and in the brain expecially, reduced CO2 causes vasoconsstriction. The result is the significantly reduced oxygen delivery to brain cells I've already mentioned. The brain can't produce all the energy it needs, leading to symptoms like out-of-control anxiety, anger and other emotions, and brain fog and fuzzy thinking.

Actually hyperventilation is more complicated than this because if it persists beyond a few minutes to hours, then the body starts to adapt and compensate for the changed breathing pattern - but the adaptation is far from ideally and leads to long term consequences.

What Causes Hyperventilation?

Setting aside medical problems (I'm not personally a medical practitioner) the most common cause is stress.

Difficult emotions like anxiety, frustration, anger and irritability can all trigger changes in breathing - typically they shift us towards fast, shallow chest-based breathing. This pattern typically goes with hyperventilation, perhaps because the diaphragm and other breathing muscles get habitually tight. On exhalation they don't fully relax and we don't let the air fully out. The brain's automatic (unconscious) regulation of breathing involves the diaphragm - if it's stuck in a tight state, breathing regulation is easily disrupted.

Optimal Breathing Training

Optimal breathing training means working with your breath to create the conditions for optimal performance and wellbeing. Probably the most important factor is to avoid over-breathing, in fact do the opposite by keeping your breath very gentle. There are other aspects of optimal breathing, and I discuss these elsewhere.

Why Biofeedback Is The Best Tool For Learing Optimal Breathing

Again, a capnometer measures carbon dioxide in your breath - this is known to correlate to your blood carbon dioxide. Thus a capnometer can tell you if you're over-breathing, and to what degree. (in my experience, most of my stress and anxiety clients are, at least in some context - and most of them don't know it). It's actually quite difficult to know, otherwise.

Furthermore, when you work on breathing it's difficult to know whether you're making things better or worse. In fact it's very easy, and common, to make things worse. This happens because we over-control the breath, rather like trying too hard to get to sleep at night and making your insomnia worse.

Mindfulness and Optimal Breathing Training

Mindfulness is a popular tool for training attention, focus, and emotional resilience. It works by allowing mental qualities such as calm, stillness, clarity and positivity to naturally come into being through a mindset of openness, trust and imagination, rather than willpower and problem-solving. In fact this is just the mindset we need for optimal breathing training. It's the body that knows how to breathe well, or perhaps more accurately the "body intelligence" part of the brain. It's not a matter of figuring it out, but allowing the breath to change, almost of its own accord.

Biofeedback & Mindfulness

At first sight it might seem as if biofeedback and mindfulness pull in different directions, but in fact they can work very well together. Biofeedback can enhance self-awareness, which is the foundation of mindfulness. With biofeedback training you can become skilled in setting up physiological conditions that support effective mindfulness practice. For example capnometry biofeedback can optimize brain oxygen delivery which can only help your focus, clarity and concentration.

How You Can Access Capnometry Biofeedback Training

I'm deeply inspired by the potential that biofeedback training offers and motivated to help as many people access the benefits as possible, and to make doing so as easy and convenient as possible. Whilst in an ideal world you'd probably visit my office here in York for one to one coaching, in practice that's often not possible especially if you live at a distance from me. But it doesn't mean you can't work with me.

My services are based around:

  • An online (video-based) biofeedback training course - designed to give you the key information, ideas and practices to make working with biofeedback a success. The course aims to develop emotional resilience and stress management skills, and is built around optimal breathing training, focusing on three key biofeedback parameters related to breathing, one of which is capnometry.
  • Biofeedback device rental, so that you can practice at home with the three key biofeedback modalities for optimal breathing: EMG (for muscle tension), capnometry, and heart coherence (also known as heart rate variability or HRV biofeedback).

I also offer one to one distance coaching via telephone or skype, to support my clients.

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