Breathing Part II: Coach, I Don't Have Gills

Breathing Part II: Coach, I Don't Have Gills

Abbie Fish of Ritter Sports Performance discusses the impact anaerobic, aerobic energy systems have on breathing in swimming. Along with lactate, threshold, VO2 max, heart rate zones, and maximum heart rate.

Mar 27, 2017 by Abbie Fish Fish
Breathing Part II: Coach, I Don't Have Gills
Welcome to Part II of our series on breathing. If you read Part I, then you already know the proper timing of inhaling and exhaling while swimming and why that breathing strategy is important.

This week we plan to dive a little deeper into the physiology of why breathing consistently helps us train and avoid fatigue. And when we "hit a wall" -- what we should do about it.

If you haven't read Part I, then do so HERE ​(trust us -- you will thank us later). Otherwise, let's get started.

Everyone has a maximum heart rate (MHR) value. While we all don't know our exact values, we can estimate our MHR by the equation:

220 - [Your current age] = Estimated MHR (BPM -- beats per minute)

With this value, coaches and exercise practitioners are able to design training programs based around percentages of your estimated MHR or heart-rate zones (HR zones).

Think about last time you ran on a treadmill (or elliptical). Each machine typically has a sticker with a bunch of numbers on it regarding HR zones. You'll see a number under the "Fat Burning Zone," "Weight Control Zone," "Aerobic Zone," and everything in between. These zones are all based off of what percentage of your estimated MHR value, your body is working at at that time, ​and what energy system is supplying the fuel for you to train at that zone.

General HR zone guidelines:
70-85 percent of your est. MHR is Aerobic
85-95 percent of your est. MHR is Anaerobic

For example, my estimated MHR is 193 BPM. Yes, I am 27 years old.

With this estimated MHR, if I run a 5K with an average HR of 150 BPM then I worked at 77 percent of my estimated MHR (150/193=.77). Seventy-seven percent is in the aerobic zone.

Why should I care about HR zones?

HR zones are important, because they are basis for most aerobic training programs. Aerobic, by definition, means in need of oxygen.  

When you swim, your muscles get fuel from the aerobic energy system. Swimming is an aerobic sport. With limited oxygen intake, your body can still swim but not as fast and not as long. That's the basis for aerobic training.

When you don't have enough oxygen fueling your aerobic energy system, your body initiates the use of the anaerobic energy system. The anaerobic energy system is by definition -- without the need of oxygen. Overall, oxygen is the key difference between the anaerobic and aerobic energy systems.

Beyond that, every swimmer has a threshold amount of oxygen he or she can deliver, per minute, to his or her exercising muscles. This threshold is called your VO2 max. The higher your VO2 max, the more oxygen you can deliver to your muscles and vice versa.

If you are swimming below your VO2 max, you are still using your aerobic energy system. If you speed up and your demands for energy increase and/or surpass your VO2 max level, your body will start fueling your muscles through your anaerobic energy system.

While this is all good, there is one major problem with the anaerobic energy system. That is its byproduct called lactate.

What is lactate?

Lactate is a fancy word for compound that is derived from the anaerobic energy system system.

Lactate isn't a big deal, as long as your body can break it down and shuttle it out. But if your body exceeds it's lactate threshold -- you will "hit a wall." Lightbulb, yet?

So if I combine what's happening in the aerobic and anaerobic energy systems while swimming, the key to breathing deals with maximizing your oxygen uptake while maintaining low lactate levels.

That means if you are swimming shorter, more intense events (i.e. sprints), you should breathe more often at the beginning of your race to prolong the time it takes for your lactate to build up.

And for longer, less intense distance events, you should breathe regularly throughout the race (i.e. every one, two, or three strokes) to keep supplying enough oxygen to your aerobic energy system.

You will never be able to change the fact that your body needs oxygen. But, you can change how effectively your body uses the oxygen available. Now get to training -- as that is the closest thing to gills we will ever have!

Make sure to catch Part III -- where we will finish up our series on breathing while swimming.

Abbie Fish has been in the competitive swimming realm for over 20 years. After capping off a successful career at University of Georgia, Abbie soon found herself back on the deck as a coach.

Currently, Abbie is a Technique Swim Coach at Ritter Sports Performance. She spends her time analyzing race videos and studying different style of stroke technique. If you'd like your stroke analyzed, or a swimmer of yours -- visit their website: for more information or email Abbie at