Swim School: When Do I Breathe During Freestyle?

By Gary Hall Sr. | June 04, 2019, 1 p.m. (ET)

Swim School Gary Hall Sr.

It is important to know how often to breathe and on which side to breathe on the swim portion of the triathlon.

Let’s start to address this question by considering how many breaths you take per minute on your bike or while running. 

The typical respiratory rate for any endurance event on land which is longer than five minutes is going to be in the range of 50-60 breaths per minute, or about one breath per second, assuming the athlete is putting forth a near maximum effort. 

For any event over a few minutes of duration, the energy (ATP) will come predominantly from the aerobic system. That means the body requires a pipeline of continuous oxygen supply and a continuous release of CO2 in order to meet the increased energy demands for the muscles and other bodily functions. Since it takes some time to inhale and exhale, it seems that around 60 breaths per minute is the maximum respiratory rate at which we can deliver oxygen efficiently through our lungs.

Even at 60 breaths per minute, the aerobic system cannot keep up with the body’s energy demands, so the body goes into what is called oxygen debt. In this situation, the body will derive some of its energy needs from the anaerobic system, resulting in metabolic acidosis. Even after the athlete completes the race and stops the exercise, the respiratory rate will continue to be higher than the normal resting rate for a while, until the pH of the body is neutralized.

During the triathlon competition, there is no reason to believe that the energy demands of the swim are any less than those for the bike or run. For many, the energy demand for the swim may be even higher, since the propulsion is coming from both the arms and legs and is potentially augmented by vigorous body rotation. Therefore, it is reasonable to think that the oxygen supply should not be any different for the swim than it is for the bike or run.

The challenge of the swim is how do you get the respiratory rate even close to 60 breaths per minute? Most of the triathletes I have coached swim with freestyle stroke rates in the range of 55 to 70 strokes per minute. That would mean, if they were breathing every cycle, that their respiratory rates would be ranging from 27 to 35 (one breath for every two strokes). That is not even close to the athlete’s physiological needs. If the triathlete tries to maintain any kind of vigorous pace, what then happens is that the pH lowers faster, the muscles begin to become dysfunctional and the swimmer is forced to slow down in order to reduce the energy demands.

To get the swimming breathing technique respiratory rate up, what are our options? One option is to try to get your swimming stroke rate up to 90 strokes per minute, as Katie Ledecky uses in her 800 and 1500 meter swims. At that stroke rate, her respiratory rate is 45 breaths per minute, which is a lot closer to the physiological ideal of 60. The challenge with this option is that Katie, and all of the other elite swimmers that hold this stroke rate, train for two to three hours per session, nine to 10 sessions per week, in order to build up their robust aerobic systems for swimming at this stroke rate for sustained periods of time.

Most of the triathletes I have coached train for three to five hours of swimming per week. That amount of training will simply not enable the triathlete to hold anything close to 90 strokes per minute for the duration of the swim. Spending much more time on your swim training will likely start to negatively impact your bike or run times.

Another (and better) option is to breathe more than every cycle in freestyle. While most elite distance freestyler swimmers breathe to one side only and breath every stroke cycle, I advocate that open water swimmers become comfortable breathing to both sides. With the water conditions being so variable, it is always a good idea to be able to breathe to either side. In the event waves are coming in from one side, it is safer to breathe to the opposite side to avoid swallowing water.

However, to many, breathing to both sides implies what is called alternate breathing technique, which means taking a breath to one side, holding the breath for one stroke, then taking another breath to the opposite side. With respect to the breath to stroke ratio, this is a 1:3 breathing pattern. At a 60 stroke rate, that produces a disastrous, almost suffocating, respiratory rate of 20 breaths per minute.

Many swim coaches and swimmers believe that breathing every cycle in freestyle swimming is as good as it gets with respect to respiratory rate, but that is not true. A swimmer can learn, and particularly with a low-profile breathing technique, to breathe consecutively to both sides. That does not necessarily mean breathing every stroke, which would result in a kind of endless, dizzying turning of the head in both directions for the breath.

Rather, breathing twice in a row to both sides, holding the breath for one cycle, then repeating the process, is a much better option. That technique creates a 2:3 breathing pattern; two breaths taken for every three strokes. With a stroke rate of 60 that would lead to respiratory rate of 40, which is getting closer to the physiological ideal.

One could also try using a 3:4 pattern, as I do on my open water swims, which means taking three consecutive breaths in a row, followed by holding the breath for a cycle. This technique is actually easier to learn, as the first of the three consecutive breaths is always initiated on the same side, while with the 2:3 pattern, the swimmer must initiate the first breath on opposite sides. With the 3:4 pattern and stroke rate of 60, the respiratory rate is now at 45 breaths per minute, which is even better.

Getting these extra breaths in is not just limited to triathletes striving to prevent metabolic acidosis. World record holding 1500-meter Olympic champion Sun Yang (hip-driven technique with a stroke rate of 60) takes three breaths into and out of every turn in his distance races and occasionally takes three consecutive breaths in the middle of the 50-meter pool. He also finishes his races much faster than any other competitor. Sun Yang uses a slower stroke rate than most other elite distance freestylers because of his extraordinary height (6’8”) and strong kicking propulsion.

For the many triathletes that I have converted to using the 2:3 or 3:4 breathing pattern for their swim leg, most have noted that while their swim times may not have not dropped significantly using this breathing technique, they do not feel as ‘spent’ after the swim, as they did from the lactic acidosis caused by breathing less. The result has been a better split on the bike and run and a much better race.

Practice the 2:3 or 3:4 breathing pattern in your swimming breathing technique in workouts and you will become more comfortable with this technique and the process of breathing to either side in open water freestyle.

In our final article on swimming breathing technique we will next discuss what to do with the air in your lungs after the breath.

Yours in swimming,

Gary Sr.


Gary gives more tips on breathing in these videos on The Race Club site. 

Gary Hall Sr. is a three-time Olympian who now directs The Race Club (Theraceclub.com) in Islamorada, Fla.


The views expressed in this article are the opinion of the author and not necessarily the practices of USA Triathlon. Before starting any new diet or exercise program, you should check with your physician and/or coach.