We have talked about breathing patterns and why they are important to safe and sustained running. That was a great conversation, but is still leaves the question of why. Why does breathing increase with speed, and should I be focusing my energy on the inhalation or exhalation side of breathing? 

Answering that question will probably change your perception on what is actually happening during respiration. Most of us are probably under the assumption that breathing rate increases because of an increased need for oxygen. In fact, our lungs are over-engineered for gas exchange; we are able to fully oxygenate our blood at rest. 

As you work harder, it is true that you must deliver more oxygen rich blood to the working muscles. This is why your heart rate proportionally increases and breathing is able to stay stable and comfortable in zone two. As you work harder, your breathing becomes heavier and quicker. As you move closer and closer to your maximal work load that breathing rate can almost turn into panicked panting.

Here’s the thing. That panicked panting isn’t because you need more oxygen. It’s because you have excess waste your body is desperate to breathe off. There are free protons released from the molecular energy cycle your cells use to provide energy to your working muscles.

These protons increase the acidity of your blood. As the acidity increases, your body uses its bicarbonate buffering system to capture the free protons and convert them into water and carbon dioxide gas. This carbon dioxide created through chemical buffering is in addition to what is produced through normal cellular respiration. 

With two sources of carbon dioxide dumping into your blood, the overwhelming job of respiration is to get the junk out! When we are panting during heavy exercise our bodies are not short on oxygen, they are working over time to get rid of carbon dioxide.

Because of the increased waste load in the bloodstream, it will improve your running if you focus on strong and forceful exhales while working above your threshold. Being mindful that the increased rate of respiration is mainly due to waste will help you stay calmer and more focused when your body is ratcheting up the panic and pain.