Gear & Technology, Podcast, Science and Physiology

Physiology, testing and respiratory training with Andrew Sellars | EP#361

 October 24, 2022

By  Bernardo Gonçalves


Andrew Sellars - That Triathlon Show

Andrew Sellars, MD, is the team director of Balance Point Racing, a triathlon and cycling club based in British Columbia, Canada. He is also the co-founder of sports technology companies VO2 Master (that manufactures a portable metabolic analyser) and BreatheWayBetter (a respiratory training device). In this interview, we discuss training, testing, and dive deep into breathing, the respiratory system, and respiratory training.

In this episode you'll learn about:

  • A physiological systems based approach to endurance training
  • Differences between structural and functional adaptations to endurance training
  • Andrew's approach to testing and athlete assessments, and how it has changed over time
  • An overview of the respiratory system in endurance sports
  • Respiratory training: scientific and anecdotal evidence, and practical applications

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Andrew's background

02:51 -

  • I am a physician, athlete and coach in Western Canada.
  • I have daily work, but I have two other roles with two other startup companies (VO2 Master - the first portable VO2 portable device on the market and BreathWayBetter, a respiratory training device)
  • We are trying to help improve athletes' training and testing. 
  • I have a background in physiology, so I have much experience in testing protocols and lab testing.
  • Once I finished Med School, I reconnected with an old mentor who helped me in the 90s while coaching swimming. (maybe the best coach no one has ever heard of)
  • He coached some of the best cyclists in Canada, like Ryder Hesjedal and has worked with many more world-class athletes.
  • He is a Swiss-trained physiologist and physiotherapist. (from the sports schools in Switzerland)
  • I learnt much from him and still use some of his philosophies today. He was one of the first to use lactate devices, and much of the lactate theories developed throughout the years come from his work.
  • He developed a lactate balance test, and we developed a team based on his ideas, "Team Balance Point Racing".
  • We started in 2002, and we supported a group of athletes in our valley that had aspirations to compete in triathlon at a high level.
  • Our area did not have many good coaches, so our team grew until I could not manage it anymore.
  • We have a couple of high-performance athletes that had come through the system and wanted to take it over, so that team is still running under Luke Way, and they have many athletes with excellent results. A group of junior athletes from that team exceed expectations, and now one of them is racing in the ITU races.
  • Luke started BreathWayBetter, and I get the joy of seeing teams survive, continue to thrive, and be part of the success.

Andrew's endurance training philosophy

08:17 -

  • My philosophy is that to improve something, first, you need to measure it. You also have to decide what to improve and create a specific training plan to target what you hope to improve.
  • After, you should remeasure it to see if the improvements in what you expected are actually what happened and allow the athlete to race and put your theories to practice.
  • Testing needs to be specific to what you look to evaluate.
  • The second part is testing with a goal in mind. You test to evaluate weaknesses and physiological changes you can adapt over time.
  • The human body is a complex system that balances seven different subsystems.
  • When we test, we look at all those seven systems. We look at the cardiovascular system (heart and blood vessels), the respiratory system (lungs and air moving muscles), the skeletomuscular system (muscles and bones and how they fit together), the neurological system (coordination of the muscle and bones), the metabolic system (how the system uses fuel to create energy), the psychological system (how the brain manipulates the emotions).
  • The seventh system is the combination of all those systems and their interaction.

Example of Andrew's philosophy

11:09 -

  • A good example is the cross-country skier. They come to us for testing because they found some performance limitations.
  • They might have good technique and can ski as fast as everyone else in a short sprint, but they struggle to keep up in a 10 km race.
  • In an ideal world, we would test him on the skies, but in the off-season, we do not have access to snow or a skate mill, so we cannot simulate his effort indoors.
  • So we tested that athlete running and cycling. He was doing cycling as an off-season sport, but we looked at both cycling and running performances to see if we could find physiological limitations.
  • That athlete had two limitations: he had an excessively high heart rate early in the test, meaning they had a small heart that had to beat quickly to provide the output they needed for performing.
  • He also had an excessively high respiratory frequency, so he was not using his diaphragm correctly.
  • With these simple tests, he changed their training and had a much better rest of the season by doing longer intervals on the skies with lower heart rates and slower breathing patterns.
  • If they did not test, coaches would not get this data and would try to push them harder and harder to tolerate that effort.
  • It would reach a point where athletes would burn out, and coaches would tell athletes they did not have what it takes to perform at a higher level.
  • Concerning this intervention, the athlete had to drop the intensity below an intensity that triggered her heart rate.
  • For the bulk of their sessions, her runs became walks. After a couple of weeks, she could start jogging with a lower heart rate and running on flatter ground, but every time she would do hills, she would have to walk.
  • We had to take an elite athlete and make her go slow. (adapting her training to the heart rate)
  • Initially, she would not allow her heart rate to go above 130 bpm, but her training passed from running on the trails to walk.
  • We were also doing specific respiratory training with her. Initially, it was mostly education on how to use the diaphragm and rib cage to allow proper respiration.
  • At the time, we were using the "Spirotiger", the only device for Isocapnic hyperpnea training (maintaining CO2 levels). However, it was expensive and inaccessible for most athletes.
  • This led to the development of our product to do this respiratory training and the creation of BreathWayBetter.

Structural vs functional limitations

17:00 -

  • If we look at performance as a complex array of all those complex systems combined, the changes we expect from the heart are divided into different areas.
  • Training has an immediate effect on the heart rate and a structural effect over time.
  • When we talk about function and structure, we talk about the physiological changes resulting from training and the areas where you can improve all of those systems with specific interventions.
  • When we talk about structures, we mean the building blocks of each system.
  • The heart is a four-chamber muscle with a specific size and pumps a specific blood amount (stroke volume).
  • If you combine the stroke volume with the heart rate frequency, you get the cardiac output, which is how much blood the heart pumps per minute.
  • Everyone has different hearts. A bigger heart allows a person to push more blood into the system and give you a better performance. (structure)
  • The heart's function is how fast it can beat and how quickly it can relax. If you have a big heart that does not beat fast, you may have a structural advantage but not the function to use that structure efficiently.
  • Combining function and structure gives us a better path to higher performance.
  • We look at the athlete's structure and analyse what would be ideal. (in the case of the heart, a big, with some reasonably thick walls)
  • We know we can improve heart size through specific training interventions. 
  • The largest hearts comes from athletes doing low-intensity training for years. (e.g. Norwegian cross-country skier)
  • Norwegians start training from a young age and do a lot of volume at low intensities. (developing bigger hearts, but it takes much time)
  • Some of the changes we want on the athletes should be structural changes. However, few studies went long enough to reflect structural changes. (e.g. any study with less than 12 weeks does not look at how training impacts structures)
  • Most of the studies are about functional changes, which limit what is possible to change.
  • Most studies that say you cannot change VO2max do not address the structural changes that can happen. These changes are significant and underreported in science because of the time limitations in the studies.
  • If you take a training plan to improve your heart size, your heart will not differ in 6 weeks. It might change the function by allowing the heart to beat faster.
  • You can do interventions of how your heart beats quickly. (these performance improvements come from functional changes)
  • Using your structures is a functional component that we can train quickly, and you can see dramatic changes.
  • For example, I participated in a study where they looked at bicep strength. The study put us on a six weeks strength program to improve strength and see if we had hypertrophy.
  • They did MRIs and tests to evaluate the cross-sectional area and implemented different protocols for strength training.
  • I was in a group with extremely high intensity and low repetitions.
  • I was doing 2-4 reps at the maximal or super-maximal intensity with some assistance from a person to improve the bicep curl.
  • With straight arms, for example, I could curl 50 pounds. At the end of six weeks, I doubled my strength. (I could curl 120 % of my maximum with 0 % to the cross-sectional area of my bicep)
  • There was no structural change, but I could recruit more muscle fibres, making a neurological and coordination change in my ability to curl with no structural change.
  • Some athletes were on a hypertrophy program and saw no difference because the program had six weeks.
  • If you put those athletes through a protocol of 3-6 months, you will start to see hypertrophy.
  • If my goal was only strength, what I was doing was fantastic, but it would max out in six weeks.
  • Athletes get a plateau after six weeks because they have functional adaptations over that period. Still, they will not continue seeing more functional changes in their exercise.
  • The only way to make further changes is to make them structurally.

The differences in triathlon

26:49 -

  • I grew up as a swimmer, but I was never competitive, even at a local level, but I kept swimming (played water pool at the university level)
  • I started coaching because I was frustrated that I could not compete against bigger-size swimmers and paid my way through university.
  • I would travel around BC clubs and coach teams of 100-150 kids from 6-16 years old.
  • In the 80s, I loved running and was good at swimming. I only needed to learn to ride a bike.
  • I loved the multi-disciplinary nature of it.
  • Swimming is a technical sport. You can be a fast swimmer but not be particularly strong or fit.
  • If you go to any swimming pool and put an age group with a kid that swam since they were six, that kid will win every race against that adult.
  • These differences go back to differences in structure and function.
  • You can put the most extraordinary triathlete specimen against a kid, but if that triathlete did not swim in their youth, the 10-years old child would beat them.
  • Triathletes have structural physiological advantages but do not have the function to have proper technique.
  • So, in the triathlon, I would look at individual limitations. If I am coaching a triathlete that is a non-swimmer, I will focus primarily on technique.
  • There is no point in making them move their arms faster or breathe a better breathing system if they cannot move in the water efficiently.
  • They can do their cardiac and physiological training on the bike and run.
  • So, we focus primarily on the swimming technique. Some experienced athletes need to look at the physiological training also on the pool.
  • For the other sports, it is the same thing. Depending on their background and training history, they can find the limitation in cycling is cardiac output vs respiratory vs muscular vs metabolic. (cannot sustain high loads due to glycolytic or aerobic limitations)
  • We find the limitation and work on that. And it could be the same limitation for running.
  • However, when Lance Armstrong retired from cycling and wanted to run marathons, he had one of the higher VO2max ever recorded, and people started trying to predict how fast he would run.
  • People said he could run a low two-hour marathon with those physiological parameters. He had not run in 20 years and came from a cycling background.
  • He signed up for the Boston Marathon and saw him running, and he did not have the coordination to run close to that pace.
  • It is a perfect example of translating cycling into running. Lance's functional running capability did not match his physiological ability. 
  • He broke three hours and said it was the hardest thing he had ever done.
  • He could not absorb the load of running a marathon, so he did not have the musculoskeletal structure to support the running load. He had no neurological ability to run with a long stride and high cadence.
  • He had cardiovascular and respiratory fitness, so he did not need to do any training on that.
  • The training for Lance Armstrong to run a marathon would be completely different than a typical person that develops different structures over years of training.
  • Therefore, our approach to triathlon training is individualised, based on the physiological testing of athletes.

Training a highly gifted physiological athlete

35:16 -

  • When I started Ironmans in 2001, I planned to do only one.
  • So, I thought I would only devote a year to training for an Ironman.
  • However, after only one year, athletes understand that they are only getting started in what is potential for the changes they can make.
  • I would challenge coaches whether they should be coaching people for a year or whether they should be training people for life.
  • The first thing I would say with an athlete like Lance was to do more than just one marathon.
  • The potential for Lance to become a marathon runner in 10 years is infinitely higher than it would be a year from now.
  • If I had only a year, I could make some structural changes in that time.
  • We could train him to adapt his musculoskeletal system to run more smoothly and efficiently.
  • First, I would focus on flexibility and strength for specific running muscles and adapt some strength gained on the bike to benefit him more for running.
  • There is a shift from a quad dominant to a hip and hamstring strength.
  • We would test him to see his limitations. I would look at how he runs now and his coordination and running efficiency.
  • In the first six weeks, I would evaluate how he would adapt. 
  • I would not set a yearly training plan. I would look at what Lance is doing currently and his ability to produce good stride length.
  • I would work on that limitation and then test if it is working.
  • If he has a slow stride rate, we have to increase it. The training will focus on lengthening the stride length if he has a naturally high cadence but a short stride length. (increase flexibility/strength)
  • Only two things affect running speed: how fast your feet move and how long your stride is.
  • There is an optimal stride length for every athlete that you can physiologically/metabolically handle.
  • Initially, the limitation would not be cardiovascular and use of oxygen well.
  • In Ironman, an exciting finding is seeing athletes start the marathon with a long stride length and low cadence, holding that form throughout the marathon.
  • The ones who will be successful will be those with a faster cadence. And it is why marathon paces in the Ironman are slow.
  • Their bike and swims times are fast, but the running times are not insanely fast for a marathon.
  • As so many people are doing it, we now understand that you cannot run "as a runner" an Ironman Marathon.
  • The most successful triathletes with a running background are more on the women's side.

Testing methodologies and protocols

44:17 -

  • I do not do much testing on other athletes, but I test myself a lot.
  • Luke has taken over the testing procedures for Balance Point Racing.
  • Most of the athletes we work with are triathletes or cyclists.
  • All of them are endurance athletes, although Luke is advising some cross-fitters.
  • I would test the athlete in the sport they are doing. (swimming, biking and running)
  • Of course, we test biking and running separately.
  • The second part depends on the athlete's background. If I come with a background in swimming, my testing procedure is different than the testing I do with a triathlete with a cycling background. (test their coordination and technique instead)
  • If I am testing a swimmer, I must examine the physiological side.
  • We can do VO2 testing on the pool. I have not done much of it, but we can identify respiratory limitations in swimmers that can hold them back.
  • If you fall off the pace in an ITU race, you will never catch up because you will end up chasing the front-pack.

Physiological testing in the swim

47:47 -

  • You can do a graded exercise test on the pool.
  • We set a specific distance (e.g. 200m), and swimmers slowly increase intensity over time.
  • If you have a VO2 Master, you can look at VO2 and their metabolic work in the 30s rest between sets. Athletes can pace themselves, but you can also set a timer for them.
  • You would do 5x200m at an increasing intensity and look at how they breathe in their rest period between each set.
  • We look at respiratory data (frequency, breathing depth and oxygen consumption)
  • You can add HR or Moxy monitors. Some coaches could use Moxy monitors successfully.
  • I do not use lactate monitors.
  • Swimming in the pool for beginner swimmers is challenging because they cannot pace themselves well.
  • If you have a weak swimmer, doing long sets will make them too tired and fast to do five sets of a graded set.
  • The Norwegian team has been partnering with us to expand our ways of using it and lead the way we interpret data.

Cycling and running test protocols

52:53 -

  • For years, we did standard step tests (intervals of increased intensity).
  • You do not need to make maximal efforts with athletes because, as endurance athletes, we are more interested in understanding what happens at racing intensity.
  • We start testing at a low intensity and go in a graded test until a moderately high intensity.
  • With the balance point test, we would bring them back to below the balance point threshold and do a second test back up with long intervals to determine the exact point where the threshold is.
  • We do the first ramp to show where lactate begins to accumulate and a second ramp to verify where the balance point is.
  • Once you have done it many times, you realise every athlete is different, so you can't study it the same way science studies look because the test protocols would be different for two different athletes.
  • We might do the first ramp test, but for example, the "recovery between the first and second ramp tests is different for different athletes, and the test adapts to it.
  • With the Moxy, we can quickly look at the physiological changes that correlate well with lactate.
  • After a few years of using muscle oxygenation, we dropped the need for using lactate.
  • Lactate is a marker for what is happening in the muscle, so you have to wait a minute to have a result of what is happening. Moxy allows looking instantaneously at the muscle.
  • We use 2-3 Moxy monitors, an HR monitor, a VO2 Master and some methods for measuring performance (power, pace).
  • When looking at performance, we must understand how the athlete is at a specific intensity. Therefore, doing 8-10 minute intervals is essential. What happens in the first three minutes gives us an idea, but what happens in the next five will give us more information about the stability of that intensity.
  • Moreover, we can look at recovery metrics after the stimulus.
  • We developed a 5-1-5 test. (five-minute interval, one-minute rest, five-minute intervals at the same intensity)
  • At the lower intensities, you will find stability in the first step.
  • During the one-minute, we can look at how athletes recover a fascinating insight into what "system" limits the most.

Why recovery between sets allows us to understand limitations

58:21 -

  • For example, let's start a test at 100 W, and data will stabilise quickly.
  • HR will come up quickly to deliver enough oxygen to the muscles to produce 100 W. It might be such a low intensity that you do not need to stabilise your breathing. A random breathing pattern will still provide enough O2 and CO2 to be stable.
  • At the end of five minutes, things will not change from the three-minute mark.
  • When you stop cycling, your HR will start to slow down. If your HR were beating at 90bpm to produce 100 W, it would go to the resting HR during recovery.
  • The cardiac decrease reflects your cardiac reserve, your ability to sustain that wattage, and how quickly you can recover.
  • The same happens with the respiratory rate. Your VO2 number will slowly drop, and all those parameters will start to drop off.
  • This trend will change at different intensities.
  • After 30 minutes of testing, we are at 300 W pushing hard.
  • HR is higher, the legs work harder, and your systems get stressed.
  • When you make the one-minute recovery, we can see which systems can recover in that period and which don't.
  • You may find that HR was at 165 bpm for 300 W but only comes down to 150 bpm for one minute, meaning you have a slow recovery of your heart.
  • Suppose you can recover your breathing but not your HR. In that case, you may have a solid respiratory system with getting too taxed at 300 W, and your cardiovascular system can be your limiting factor.
  • You can also look at the recovery of the muscles with Moxy. If they cannot recover oxygen levels, they will remain "tense", giving a unique insight into your muscle limitations.
  • We do this protocol for both running and cycling.
  • We take data from HR, Moxy and VO2 Master.
  • We added body CORE temperature sensors to that dynamic to give us more indications of what is happening.

Getting the respiratory data

1:03:10 -

  • Breathing is my passion, and it comes back to earlier readings in the 90s and audio tapes on how to become a better runner through breathing.
  • With the release of books and resources like the Oxygen Advantage, there has been a new interest in breathing.
  • All these concepts are things we were doing 20-30 years ago.
  • When we started doing VO2 testing with athletes, we saw athletes would breathe differently.
  • Some athletes would breathe fast and shallow, and others slow and deep.
  • Performance limitations would show up quickly in people that could not control their breathing.
  • The respiratory system is simple: there are only two ways to increase ventilation: the tidal volume (breath volume) and the respiratory frequency (breathing rate).
  • As intensity increases, you have to breathe faster to blow off CO2 created at the muscle level.
  • You breathe to blow off CO2 and balance your blood PH. Managing CO2 levels results from the body's need to maintain physiological PH. (7.35-7.45)
  • Outside those ranges, our body shuts down (enzymes stop working correctly, and it is not a good experience to be in that situation).
  • We used VO2 Master to evaluate respiratory rates and tidal volume, which was the primary reason for developing VO2 Master: evaluating how people breathe. 
  • Therefore, we can measure VO2 consumption, a cardiac output marker. 
  • VO2 is a measure of the oxygen used in the periphery, but to get oxygen there, you have to send it. (cardiac output)
  • The more helpful information is how athletes breathe.
  • We can find limitations on athletes with respiratory testing.
  • Everyone thinks they know what VO2 is, but the device's power is exponentially higher for looking at the respiratory system. (the only device right now where you can test in the field)

Respiratory limitations

1:09:38 -

  • Limitations are either structural or functional. 
  • The structural limitations will be around the volume. To improve breathing pattern efficiency, you need to produce a specific level of ventilation. (change volume or frequency)
  • The body size is one structural limitation. Lung volume correlates with height.
  • Another limitation is how much the ribs can move. Your thoracic cavity (the "cage" that holds the lungs) attaches to the spine, and the way it attaches and hinges from the spine is a secondary volume limiter.
  • The third limitation is the diaphragm. It will depend on how far it contracts, and how far it can move into the belly can be a structural limitation, but often is a functional limitation.
  • After analysing the structural and functional limitations that affect volume, we look at the frequency limitations.
  • We look at structures first. We want long-term improvements because we will only make short-term functional changes.
  • We always tell athletes that we will look at their bodies in the next 5-10 years, so we have a lot of time to access those structures.
  • With BreathWayBetter, you can access this information, but you can also use VO2 Master or a metabolic cart on how they are using their structure.
  • Respiratory frequency is a coordination issue (functional limitations). Still, it would help if you had muscles that allow for respiratory muscle frequency (structure limitations - a diaphragm that can contract quickly and abdominal muscles that can coordinate and blow out quickly).
  • The ability to breathe in and out is similar in cycling because the limitation is not on how fast you can contract but how fast you can relax.
  • At a graded test, we can see the point where the athlete's respiratory frequency at which they lose coordination.
  • Therefore, that is part of the test: evaluating how fast they can breathe while controlling the patterns.
  • Ventilatory thresholds are changes in the respiratory pattern rate and volume) in a graded exercise test for most athletes.
  • VT1 is the aerobic threshold, and it is moving from a resting pattern of breathing to a slightly higher rate (and higher volumes)
  • "increasing ventilation to adapt to the increase in workload."
  • That respiratory pattern will remain stable for some steps as intensity increases until an increase in intensity changes ventilation patterns that coincide closely with LT2.
  • As you start relying on the breakdown of sugars that produce lactate, you require a higher oxygenation level. However, what drives that is the increased level of CO2 produced to buffer the acid produced from glycolysis, which leads to an increase in ventilation and an increase in O2 to balance that PH.
  • It is understandable that your ventilation changes at your lactate threshold from a physiological perspective. (the production of acid, not lactate, from the breakdown of sugar)
  • Most people control the pattern until VT2.
  • Most athletes lose coordination above VT2, but some athletes can still maintain a good pattern, showing they do not have a limitation on the respiratory system.
  • VT2 is a sudden increase in the ventilatory value resulting from poor coordination above VT2, and you have a limiting respiratory system function.
  • If they have good respiratory coordination, the values will be much higher.
  • Most athletes without respiratory training as part of their program lose control of their breathing and cannot find good patterns at high intensities.

Respiration training

1:18:06 -

  • If they have a limitation in tidal volume, there are specific exercises to improve thoracic mobility, diaphragm contractions (whole diaphragm excursion)
  • We do not have an isolated way of measuring the volume in BreathWayBetter, but you can see the changing volumes as it is a re-breather. (it is a benefit of Spirotigger - it measures the air volume)
  • The devices that increase resistance do not give you the ability to improve volumes.
  • If the limitation is volume, we must educate on how to use the diaphragm properly and create positions that improve thoracic mobility to increase volume.
  • If the limitation is respiratory frequency, we work on coordination.
  • Much like cadence exercises for running, you can break it down into smaller bits and have the athletes run with speedy running patterns.
  • You can do the same thing with BreathWay: making fast breathing patterns with smaller volumes.
  • Over time, we maintain the increased breathing rate and increase the volumes.
  • The goal is to maximise respiratory frequency and add volume to that.
  • If you do those exercises without a device, you will hyperventilate, blow off CO2 and get dizzy.
  • The reason for breathing fast is to eliminate CO2. If you are not producing CO2, you will do it for a short period.
  • Patterns like Win Hof's breathing have challenges because you have limitations on time because of the physiological impact of breathing.
  • Variations in CO2 levels will profoundly affect the body and brain chemistry, forcing you to stop that.
  • BreathWay allows you to control CO2 levels and train your respiratory system for an extended period.

Respiratory training and its effects on performance

1.21:53 -

  • We have a library of articles on the BreathWayBetter website.
  • The origin research came from Switzerland which was on patients with respiratory issues.
  • The theory was that if we could improve their respiratory system, we could improve their activities in daily living.
  • That work led to the development of Spirotigger, which was a way of training the respiratory system without taxing the other systems.
  • If you put someone with severe asthma on a treadmill and start walking, breathing and walking were too challenging.
  • We could measure how they breathe and improve if they only focus on breathing.
  • People with asthma have a problem, but the question is if healthy people could also have limitations.
  • The first test was taking an isocapnic breathing bag and having cyclists breathe as fast as possible for five minutes.
  • Then, they put them on an ergo-meter and made them do a 20km time trial.
  • Nobody could hit the same number after breathing hard for five minutes.
  • So, all the research came from that study where cyclists got fatigued from only breathing. So, breathing can be a limiting factor for performance.
  • Most of the breathing at a high intensity should be coming from the diaphragm.
  • The diaphragm is a skeletal 100 % slow-twist muscle. The additional abdomen and intercostal muscles also fatigue like any other muscle.
  • If you need to support fast breathing and those muscles are already tired, you cannot keep up with the elimination of CO2, and your physiology falls apart because you produce more acid and your PH goes off.
  • So, if you train the thoracic muscles to delay fatigue, you can improve your performance.

Modalities where breathing might be a limiting factor

1:25:50 -

  • One challenge in Kona is that it is hot and humid.
  • The heat and humidity will force different breathing patterns under the same load.
  • So, while you might ride 200 W for five hours without the breathing limiting you at sea level and in a cold environment, if you have to breathe differently in Kona, your thoracic muscles will suffer in that race more than in others.
  • People with unrecognised respiratory limitations suffer more in Kona because it changes how they run. (cadence slows down or strides length decreases)
  • In a sprint triathlon, you will probably be breathing at your maximum for most of the race.
  • If you have a respiratory limitation, it will be a functional limitation. (breathing fast for short periods)
  • For Ironman athletes, we need to consider the structural limitations.
  • If you have a weak diaphragm, you might breathe easily for 6-9 hours, but if your structure cannot hold on for 12 hours, you will end up walking in the marathon.

Why the respiratory system has such low recognition in the sporting community

1:29:43 -

  • I think it is historical. There were well-known people in the past that said that the respiratory system was not a limiting factor for performance.
  • And it came from work that showed people's oxygen saturation never dropped when exercising.
  • We have been doing respiratory training for decades, and many athletes have been doing respiratory training and not advertising it.
  • I believe they have found a tool that gives them a performance advantage, so why would you share it with everyone else if it gives an advantage?
  • One of the early adopters of respiratory training was Nino Shurter, and the whole Swiss team collaborated with Spirotigger and did respiratory training with their athletes.
  • You can see how dominant those cyclists were.
  • I believe it is a lack of awareness and understanding of the benefits.
  • The new books that came out are increasing this awareness for practitioners, and I think it is an untapped area for most athletes.

Other devices

1:33:29 - 

  • Other advertised devices are not isocapnic devices, which offer resistant breathing.
  • Some studies show if you breathe through resistance, you will increase thoracic strength.
  • The challenge is that you have to be exercising.
  • One benefit of isocapnic devices is that you can do it at rest.
  • The other challenge is that the added resistance will worsen if you do not have good respiratory mechanics or maximise your lung volume.
  • If you put too much weight on a barbell, athletes will only do the exercise in the range of motion they can handle for that weight.
  • You want to maximise the movement in respiratory training.
  • You might get strong with resistance devices but in a limited range.
  • Resistance devices do not teach good respiratory patterns.
  • If you get strong and can only do it for a short period, it might not give you any advantage.
  • There are two primary focuses in the literature: RMT (respiratory muscle training), which focuses on muscle contraction ability, and IMT (inspiratory muscle training), which we evaluate using a resistance device. - They look at muscle strength and single-breath power.
  • There is no evidence that single-breath strength significantly impacts endurance performance.
  • It makes sense that this does not help endurance performance because you can increase your one-max squat, but it might not improve your cycling performance if you do not do much.
  • The same happens with the respiratory system: you need the ability to contract those muscles for the total duration of your event.

Examples of using the respiratory system in the racing strategy

1:38:20 -

  • Cross-country skiing takes the best parts of swimming (technical component, small muscle use and flow) and puts it into an outdoor environment where everything changes every moment.
  • We have one of the cross-country ski locations only 30 minutes from my house.
  • One athlete we tested with respiratory limitations used the VO2 Master with her coach.
  • The numbers were not precise, but that was not the goal.
  • She was making a 3km loop from a future race and did it with the VO2 Master. First, she would do a baseline loop, then an easy loop, while I looked at the data.
  • She would make the loop with the breathing recommendations in the final run.
  • In cross-country skiing, we have short sharp climbs followed by steady descents, where she will recover.
  • On the short climb, she could single stride for most of the length before switching to off-set.
  • She has good technique, but she would switch to a less efficient skiing pattern, and that would be the issue that would slow her down.
  • The athlete could not hold that technique because she would lose control of her breathing ten seconds before switching patterns.
  • On single strides, she was breathing at 30 bpm, then shifting dramatically to 45-50 bpm. Ten seconds late, she would switch technique, which would give her a pattern of 40 bpm.
  • The respiratory change would drive the technique change because she was producing so much CO2 and could not blow it off with 30 bpm.
  •  We tried different interventions: faster single strides to see if she could breathe 32-33 bpm, but that did not work; then we tried off-setting earlier in the climb, but that was slower.
  • What she did was over breathing on the flat (hyperventilating) to start the climb with a low level of CO2. This way, she could maintain her technique more during the climb.
  • She got so good at pre-breathing that she could do the whole climb without losing technique, dropping her time on the climb by 12s.
  • She was doing a five-lap race, meaning a 1min30s difference.
  • This difference allowed her to go from the middle of the pack to exit the climb, leading the race.
  • She won those Nationals and attributed that victory to the 12s she saved on the climb.
  • So, we identified someone with a respiratory limitation, trained them on how to control their breathing, and took them to their sport to see how they use their respiratory system and have an intervention that increases performance.
  • Athletes can do this research without any equipment. They can try to do a Strava segment counting breathing and then using different breathing patterns.
  • If you are making short efforts, you can dramatically shift how your body responds to breathing. If you pre-breathe before and do slow breathing the whole climb, the energy going to breathing goes to the legs and can make a 15 % difference. (15 % of your cardiac power output at maximal breathing intensity will be to drive your respiratory system. Any benefit in breathing will lead directly to performance improvements)

Rapid-fire questions

1:46:56 -

What is your favourite book, blog or resource?

Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance by Alex Hutchinson 

What is an important habit that benefited athletically, professionally or personally?

For me, learning and controlling my breathing.

Who is someone you have looked up to or who has inspired you?

Juerg Feldmann.


Bernardo Gonçalves

Bernardo is a Portuguese elite cyclist and co-founder of SpeedEdge Performance, a company focused on optimising cycling and triathlon performance. He writes the shownotes for That Triathlon Show, and also produces social media content for each new episode.

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