This is a brief overview of how breathing can impact your running. Keep in mind that breathing and the heart are complex organs inside complex biological systems. This is the equivalent of explaining chemistry to an elementary school student, it's an oversimplification.
Related: Running and Breathing Video
I also want you to keep in mind that there is limited research available on the quantitative results for this subject, so it is theoretical. As always, I would suggest reading and experimenting with the different aspects, listen to your body and see if or how much it works for you.
In a previous blog, I discussed the importance of and how to listen to your breathing, understand what it is telling you and how it relates to effort level.
Mechanics of the breath
There are two large aspects of breathing while running that we have some control over:
How deep you breathe.
How quickly you breathe.
Although you don’t have complete control over these aspects, you are consciously able to change how deep and how fast you breathe. So which is better for you? In order to understand the answer we have to understand how each aspect impacts our body. But even before that we need to understand the muscle that helps us control these aspects: The diaphragm.
The Diaphragm
The diaphragm is a powerful muscle. Because our body is, generally speaking, a closed environment, as the diaphragm expands and contracts it actually impacts the rest of the body. To keep this brief, I’m only highlighting what I believe are the most important aspects that the diaphragm impacts: your blood flow and therefore your heart rate.
As the diaphragm contracts, it creates negative pressure in our lungs and pulls air in. The negative pressure from the contraction also pulls blood toward the center of your body. One study from NIH (National Institute of Health) stated that “the abdominal muscles and the diaphragm might play a role of an ‘auxiliary heart.’”* Implying that your diaphragm and abs can influence your heart rate. When we have two mechanisms that are influencing the same outcome (ie. blood flow), it's better or more optimal that they work together than against each other.
In order to understand how we can help the diaphragm work with the heart, we must understand how the aspects of breathing are related to the diaphragm:
Deep vs Shallow Breathing - The deeper the breath the more negative pressure is created and the more air is brought in and the stronger the pull on the blood flow.
Short vs Long Breaths - The quicker the breath, the more rapidly the diaphragm contracts and relaxes meaning that the negative pressure pulls on the blood flow are weaker and more frequent.
Purpose of the Breath in Running
So when it comes to running, the breath is about getting oxygen to your cells. Just in terms of breathing and the heart, there are two main limitations that might occur when you run: lack of oxygen and high heart rate. Generally speaking, for faster shorter distances, a lack of oxygen will more likely be the limiting factor, while for longer races a high heart rate will more likely be the cause of exhaustion.
So depending on the purpose of your run and therefore the potential limiting factor, you will want to change your breathing to help prevent progression toward the limiting factor:
Short Fast Runs (Lack of Oxygen) - Short fast breaths are great for getting oxygen into your body and you care less about a high heart rate.
Long Races (High Heart Rate) - Deep long breaths will help put the least amount of counter flow on the heart rate and make it easier for the heart to work with the diaphragm.
From the limited research that I have done (April 2021), I have not seen any scientific studies that have refuted or confirmed this theory. However, in my experience, each type of breathing stated above works better for me on those types of runs. I also stress that it is important for you to try them out and see what works for you. Here are some simple exercises in the Exercises section below that you can do to see what works best for you.
Remember that there is a progression to breathing and that it is important to be observing and collecting data about your breathing while you exercise. You can also control your breathing by speeding up and slowing down. For more detail see the article on Run Basics - Breathing. Your breathing is directly related to your run effort which is why I think it's important that all runners learn to gauge their effort level and run by effort.
To limit the size of this article and information overload, I'll continue this topic is Form Focus Breathing level 2. In there, I’ll discuss the progression of breathing, distinguishing your lactic threshold and recognizing the rate of change of your breath.
Breathing Exercises
Distinguishing Deep, Shallow, Long and Short breaths
Required Material: none
Duration: 30 secs per aspect, 2-3 mins per stage
Stage 1
Standing or sitting still, perform the following
Collect your baseline state (what's your current state, how does your breath feel? How does your body feel?)
For 20 seconds, take Shallow Short Breaths
Compare how you feel now to your baseline.
How does your breathing feel after?
Do you feel like you have enough oxygen
Do you feel like you are more or less relaxed?
Repeat this exercise for the following breaths:
Shallow Long Breaths
Deep Long Breaths
Deep Short Breaths
Think about which one you enjoyed the most, which felt most natural.
Stage 2 - Repeat the exercise while on an easy run
Stage 3 - Repeat the exercise while on hills or at a faster pace.
For each stage, observe how you feel and which you think would be best for fast runs or easy runs. This should give you some data to start to recognize what feels best for your body. Continue to observe and play with the balance of these aspects. Remember not to over analyze this, let your breathing be natural. The further you try to change your breathing from what it naturally does, it will require more focus and energy. We want to guide your breathing not force your breathing. If it is ever effortful, then that is an indication that you’re forcing not guiding. This is a learned skill and takes time to develop. Good luck!
Observing Natural Breathing
Required Material: none
Duration: 30 secs per aspect, 2-3 mins per stage
Find a hill with a moderate incline (or stairs if hills are not available)
Collect your baseline state (what's your current state, how does your breath feel? How does your body feel?)
Easy jog up the hill or stairs for 30-60 seconds
Compare how you feel now to your baseline.
Where was your breathing along the spectrum of breathing while doing the easy jog?
Resting -> Easy breathing -> Race breathing -> Sprinting breathing
Did you feel like you had enough oxygen?
Did you feel more or less relaxed?
Go back to the bottom of the hill and take some time to recover.
Repeat Steps 2-5 for each of the following types of running:
Fast jog (not a sprint)
Easy breathing (try to find a consistent pace to jog up the hill that keeps your breathing steady at easy breathing)
Make sure that you’re comparing how you feel and your breathing between each type of run
*https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4703783/#:~:text=In%20particular%20we%20found%20that,shifting%20toward%20the%20pulmonary%20circulation.