Podcast, Training

Aerobic training and testing with Scott Johnston | EP#326

 February 21, 2022

By  Bernardo Gonçalves


Scott Johnston - That Triathlon Show

Scott Johnston is an endurance sports coach, author, and co-founder of the coaching business Uphill Athlete. The main focus of Scott and his company is coaching mountain sport athletes, like mountain runners, climbers, and ski mountaineers, but Scott also has an extensive background in more traditional endurance sports like swimming, cross-country skiing, and even triathlon. 

In this Episode you'll learn about:

  • What do we mean by "aerobic base", and how do you develop a really strong aerobic base?
  • How should aerobic training be executed?
  • How and when should you balance high-intensity training into your training program?
  • Training zones: Scott's recommendations for how to assess and use training zones
  • Testing: the Heart Rate Drift test for assessing your aerobic threshold

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Scott's Background

03:42 -

  • I am the co-owner for the online training platform Uphill Athlete, and we wrote two books: "Training for the Uphill Athlete" and "Training for the new Alpinist".
  • We deal with all kinds of sports. We started primarily working with alpinists and mountaineers, and after the release of the first book, we received some contacts from an athlete called Killian Journet.
  • He contacted us asking if we could do something for runners and skiers who race in the mountains and convey the same information.
  • Therefore, our second book has Kilian as co-author, and it deals with the sport's types we are more familiar with in the endurance world.
  • What gave me some authority in this area was that my business partner Steve House was a professional alpinist. I coached him through the bulk of his career, and people considered him the best high-altitude alpinist in the world.
  • The process that Steve and I used to train him was pretty unconventional. (different from what the other climbers were doing at that time)
  • That point caught the community's attention, and people started asking Steve how he trained to achieve those feats. And Steve would always answer that he could tell them, but he had to write a book. That was how this process started, and we wrote a book.
  • This period of coaching Steve also coincided with the 2nd half of my coaching career of cross-country ski racing. I started coaching a junior program around 2000 and had 120 kids in the program. We produced four Olympians out of that group, and some went out to achieve excellent results in the World Cups.
  • I competed as a cross-country skier at a World Cup level, but with poor to mediocre results. I was not a good athlete, but this gave me a lot of exposure to the sport.
  • At the same time, I was quite an active alpinist. Therefore, I understood the demands of endurance sports training combined with the unconventional sport of alpinism.
  • I have an engineering and mathematical background to work in those areas. However, when I was younger, I was a swimmer and was part of an Olympic Development Program in swimming during my high school years.
  • I competed at a high level in that sport as well.
  • In conclusion, I had access to high-quality coaching methodologies and training philosophies from my teenage years.
  • I had some exposure to triathlon in one year when I was training for cross-country ski racing. A friend told me I should do a triathlon because I had a swimming background and could run fast. So, I race a season for triathlon as well.

Lessons Scott learnt in each sport.

10:10 -

  • In swimming, you become mentally tough. In that Olympic program, the coach I worked with was an adherent to Arthur Lydiard's training back in the mid to late 70s.
  • Arthur Lydiard was the first proponent of high volume and low-intensity training. My coach started applying those ideas to the heart in swimming.
  • We trained typically five hours a day for six days of the week. Each day, we would do about 20 000 m. Therefore, we would spend five hours a day staring at the bottom of a pool.
  • You have to be mentally tough to do that daily. (or foolish)
  • I was a young person that would do everything if you pointed me in the right direction. I believe this experience toughened me a lot.
  • This process had a good effect on my fitness base. So, when I went cross-country skiing, it was liberating. I was outdoors, and it was more fun than being in the pool.
  • What I took from cross-country skiing is that the dogma regarding the approach to training can be wrong.
  • I experienced that when skiing at a high level with world-class US cross-country skiing coaches. I knew that some implemented ideas did not align with what I knew about my swimming training exposure.
  • Essentially, there was a lack of understanding of the aerobic base volume and intensity mixture. The misuse of those ideas resulted in many young athletes never reaching their potential.
  • Therefore, I started questioning that, which helped me develop my approaches.

Lessons learnt in climbing

13:25 -

  • I picked up these ideas from sports and applied them to alpinism.
  • I applied them to myself and started having tremendous success.
  • In the 80s, many of the climbers did not train. (they would only climb) That method was the tradition for years.
  • I began to apply a more systematic approach to my training and had great results.
  • When I began coaching Steve in the early 2000s, the same happened.
  • First, I understood what was happening because I had a background in other sports, and I knew how to apply these conventional methodologies to alpinism.
  • Having that background in other sports proved valuable in extrapolating to a new situation.

Endurance base for climber and how to train it

15:25 -

  • Alpine climbs will last from many hours to several days, often without stops.
  • Steve did a climb in Alaska, where he continuously moved for 16 hours and with significant technical difficulty.
  • Therefore, there is a mixture of high aerobic capacity to keep going for an extended period, significant strength and power and high technical skills. When you get fatigued, the first thing that goes away is fine motor skills, and your technique goes down.
  • In climbing, you cannot afford to lose technique. So, maintaining fine motor skills and cognitive ability is crucial to continue climbing and avoid potentially fatal mistakes.
  • The primary importance of aerobic base is of a supportive mechanism.
  • In ultra-endurance (events lasting over eight hours), the aerobic base is fundamental to performance, but in shorter events, the aerobic base is a support mechanism to do those events.
  • Even though the intensity in these alpine climbs is relatively low because you might not move for some hours, there are periods where the intensity will be very high for several minutes to even an hour or more.
  • For example, it is the same with soccer. If your motor skills degrade when you get fatigued, even if you have good endurance, you will not play a great game if you cannot hit the ball.

The aerobic base for endurance performance

19:28 -

  • Endurance is anything longer than two minutes for me. The aerobic pathway will be the determinant source of energy for those events.
  • Even for relatively short events, having a solid aerobic base becomes essential.
  • Of course, if you are a 400m runner, it is not crucial for performance, but for a 1500m runner, the aerobic metabolic pathway is crucial.
  • The only way to train the aerobic base is to train at a level that maximises aerobic metabolism with minimal activation of the anaerobic metabolic pathway.
  • You have to train at a relatively low intensity to accumulate more training volume at that intensity.
  • Few people train 20 hours per week and have a lot of high intensity. If they have, they will rapidly fall into an overtraining state.
  • In more conventional sports, efforts last 2-4 minutes to 2-4 hours. This aerobic pace (aerobic capacity - the ability of the aerobic metabolism to produce ATP) is crucial to minimise the activity of the anaerobic metabolism.
  • Aerobic capacity is crucial because the movement behind these efforts comes from slow-twist muscle fibres. These muscle fibres work predominantly aerobically.
  • We have a repository of fast twist fibres for sprints or maintaining a relatively high pace. These fibres are alongside slow twist fibres on the muscle-skeletal system.
  • The by-product of glycolytic (anaerobic) metabolism is lactate. Some people call it lactic acid. However, lactic acid only exists for a short period. (it breaks down into a hydrogen ion and the lactate sugar molecule after its formation)
  • The slow-twist fibres close to the fast twist fibres can take up and use that lactate created and use it as fuel.
  • George Brooks discovered this phenomenon in the 80s. (lactate shuttle)
  • Some enzymes take the lactate out of these fibres into adjacent slow-twist fibres where it gets used.
  • An accumulation of lactate in the blood correlates with a reduction in force production, and you have to slow down as lactate accumulates beyond a specific point.
  • If we can increase the capacity of these slow-twist muscle fibres, they can take more lactate produced by the fast twist muscle fibres.
  • It means that fast twist fibres can contribute more to the force production before lactate increases to the point you have to slow down.
  • The aerobic base is a support mechanism for more sport-specific type training or racing. In a triathlon race, you will not spend time at that low-intensity aerobic base level. Things seem counterintuitive because people do not understand why to work on the aerobic base. And the answer is what we mentioned above. When you are in a race, and your fast twist fibres are producing lactate, we need a place for that lactate to go and use as fuel.

Intensity control for developing the aerobic base

27:48 -

  • All athletes need to improve their aerobic and anaerobic capacities, especially in shorter events. (800 and 1500 m runners, or for cross-country skiers)
  • They are two completely different metabolic systems responding to different training stimuli.
  • Therefore, you need to understand the goals of a particular training session.
  • The training volume is the most significant training stimulus concerning the training duration. These slow twist fibres have a lot of endurance, and they will require a stimulus that fatigues them to adapt. This stimulus might have to last several hours, depending on the athlete's fitness.
  • The training stimulus for the anaerobic or the fast twist muscle fibres comes mainly from the intensity of the activity. Although the duration is essential, it is more crucial for the aerobic base. How much volume we should do will depend on the athlete's level. Marathon runners run more than 100 miles per week because they need that volume to improve. The same applies to cyclists that train for stage races. They put a considerable volume of "easy riding" because it is what they need to do to increase the size of their aerobic base.
  • Training becomes more tricky when we pass from theory to practice. We understand these theories reasonably well, but it will down-regulate the other when you train either one of these systems. You will down-regulate the aerobic system if you do too much anaerobic work.
  • It is a delicate process to achieve that balance, and it is different for different sports. The recovery time between training sessions becomes critical.
  • I usually use a block training system where I try to do this with a middle-distance runner or a cross-country ski sprinter. The training block is 2-4 weeks long, emphasising one of these systems.
  • The training on the other systems comes down to the maintenance level to return to work on it on the next training block.
  • So, there is a downregulation of the primary system not trained during that period, but we hope not destroy it. The athlete responds in a stair-step approach when we return to work.
  • In one block, we try to develop the aerobic metabolism and minimise the damage to the anaerobic system, and the situation reverses in the following training block.
  • This approach requires close communication with the athlete and monitoring their performance. When you begin to see a significant dropoff in aerobic/anaerobic capacity, you need to take some action to mitigate that so you do not push one down too far. (especially the aerobic one)
  • It is possible for an endurance athlete too much anaerobic capacity, but we cannot say that about the aerobic capacity.

The Concept of Aerobic Deficiency Syndrome

34:06 -

  • I cannot take credit for coining that term. (it comes from Phill Maffetone)
  • I worked with him as a coach in the early 80s, giving me some coaching advice.
  • This term means that your ability to "shuttle lactate" is too small for the level of anaerobic work you are trying to perform.
  • So, you need to take proactive steps to eliminate that aerobic deficiency syndrome, but it is surprising how many world-class athletes come to me with this problem.
  • I know it might be surprising to hear someone who specialises in the 50 km cross-country ski race and competes at the World Cup could be aerobically deficient, and I have seen it happen.
  • On the amateur athlete level, I would guess that 80 to 90 % of the athletes that come to us for coaching are aerobically deficient.
  • First, we need to fix that problem because until we get our "aerobic engine" in an adequate size, none of the other work makes a big difference.
  • You cannot only focus on improving the glycolytic /anaerobic capacity until you develop the other part.

Accessing aerobic deficiency

36:21 -

  • There are several methods. We can use a gas-exchange mask on the treadmill, which could be an excellent way to measure it.
  • We can also do a blood lactate test.
  • And we use a tool that collects GPS and HR data carefully over a prescribed distance in the running. We evaluate how much your HR increase over that one hour, and the amount of HR increase indicates that aerobic base capacity.
  • TrainingPeaks has a metric for this parameter: the pace to HR ratio (HR decoupling).
  • When I was an athlete, we would call this HR drift. In these cases, we are trying to do with these tests to determine the maximum intensity (pace, HR, power) that you can sustain before the anaerobic system begins to kick in to make up for deficits in the aerobic capacity.
  • That maximum intensity has many different terms, depending on where you are in the world and the coaching system you have.
  • Historically, we would call it the aerobic threshold because it is the maximum amount of power/pace that your aerobic system can produce ATP for before you start relying on the anaerobic system.
  • We call it the "First lactate threshold" or "First Ventilatory threshold."
  • It is the point where the anaerobic system begins to dominate ATP production. For people aerobically deficient, it could be at a shockingly low pace.
  • People get surprised with the results because they feel fine but question why they need to run so slowly to stay in the aerobic intensity zone.
  • The reason is that your aerobic pathway can only produce that amount of ATP before relying on the anaerobic pathway.
  • Working with a world-class athlete with good performance and aerobically deficient can be challenging. You will have to ask him to take two steps backwards to correct this aerobic deficiency. And they are not going to like hearing that they need to slow down to get faster.
  • I had a cross-country skier with a remarkably high VO2max. (92 mL/kg-min)
  • He came to me because his performance had stagnated, and he was not competitive in the World Cup.
  • The first thing I did was do a running, aerobic threshold test. The first time we did this test, we found the aerobic threshold at 135 bpm. We are talking about a young, healthy male, and this heart rate was the maximum heart rate he could achieve and stay in this aerobic zone. The running pace was about 8:30 min/mile.
  • When I told him his aerobic base was not big enough, he could perform because he had incredible anaerobic power. However, he could not sustain that power for very long.
  • We went through this phase of remedial training, where we do all of this aerobic base training, and he said it was a big shock to him in the area where he lived. He was embarrassed about running that slow outdoors.
  • Four months later, we did a follow-up aerobic threshold test, and his aerobic threshold heart rate had moved from 135 to 165 bpm. So, his aerobic threshold running pace increased from 8:30 to 6:15 min/mile.
  • We realised we had fixed this aerobic deficit problem and started adding intensity. However, the athlete had a training diary of too much high-intensity with enough low-intensity. (this is what caused this imbalance)
  • His performance started improving after that.

How to do aerobic base training

45:49 -

  • First, we need to establish the upper limit of this intensity zone with one of these testing types.
  • Then, you have to understand that you can only increase the aerobic capacity from below.
  • In this case, the heart rate of this athlete was 135 bpm. He needed to train in the 130-135 bpm heart rate zone. We need to judge it from below gently.
  • If you train above it, it will not increase that aerobic base. It would push it down.
  • It is where it becomes difficult for very successful athletes to go slower.
  • If you have not done a test like this, one way to access this zone is to see if you can carry a conversation with complete sentences. If you cannot, you are probably above your aerobic threshold.
  • And that can be an easy check. If you are running or cycling by yourself, you have to talk to yourself a bit, but it is easier to train with a partner.
  • More sophisticated measurements from these tests can quantify it more closely with those methods. Some people also use nose breathing because the upper end of nose breathing tends to correlate closely with the aerobic threshold.

Balancing the aerobic and anaerobic metabolism with training

48:51 -

  • The most fundamental thing to understand with endurance training is that high-intensity training supplements low-intensity training. (not a substitute)
  • I believe the media presents this idea wrongly. For example, if you only have 30 minutes to train today, you might want to go as hard as you can for that duration.
  • While that might be a beneficial training tool, it is not improving your aerobic capacity because you are probably training well above your aerobic threshold.
  • People may believe that they will have the same training effect, but they can get it in a shorter period. However, our physiology does not work that way.
  • There is a reason for the best marathoners to train 100+ miles per week. I believe that is the first thing to gather and understand.
  • Endurance training is a high volume of low-intensity sprinkled with a small volume of quite high-intensity.
  • Stephen Seiler has done metadata studies on world-class endurance athletes from swimming, running, cycling, cross-country skiing and rowing. He tried to look at the mixture of intensity for very successful endurance athletes.
  • He found that the most successful endurance athletes did 80 % of their training sessions in the aerobic zone and 20 % in the higher intensity anaerobic zone.
  • If you read between the lines, the real takeaway is that in terms of training volume, about 90 % of their training was at the aerobic base zone and 10 % at higher intensities.
  • For many people, this is a surprise that such a small high-intensity stimulus is enough to improve the athlete's performance.
  • This aspect is the reason why endurance training can be tedious. We need to do a lot of low-intensity work, and then you can add the more "sexy" high-intensity stuff.
  • This intensity distribution tended to remain relatively consistent all year out. Depending on how much the athlete raced, more intense training would be during the competitive season.
  • Even in the build-up to their competitive season, there was no excessive use of high-intensity training.
  • My experience with world-class cross country skiers does not take much stimulus. If your aerobic base is extensive, some anaerobic stimulus will improve substantially.

Results from aerobic-base training

54:25 -

  • I learnt how to distinguish different training improvements from a Dutch swimming coach Jan Olbrecht who wrote The Science of Winning, where he goes deep in lactate dynamics.
  • He makes a distinction between aerobic capacity and aerobic power. Aerobic power is what we think of as VO2max, so one way of measuring it is doing a VO2max test.
  • On the other hand, Aerobic capacity is the maximum intensity you can sustain, while the aerobic system is the predominant ATP production mechanism.
  • At the higher intensities where you elicit VO2max, your anaerobic system contributes with much energy at that intensity. For this reason, we cannot sustain that VO2max for more than a couple of minutes.
  • Any longer than that, and the intensity will drop.
  • Therefore, VO2max does not correlate well with endurance performance. What correlates with endurance performance is the % of the VO2max we can sustain for long. The anaerobic threshold (2nd lactate/ventilatory threshold/MLSS) is a good indicator.
  • The aerobic system is crucial because improving it helps you sustain a higher percentage of your VO2max.
  • We want to elevate that threshold as high as possible in training, close to the anaerobic threshold and your VO2max.

Differences between thresholds

58:56 -

  • Successful endurance athletes have minimal differences between the first and second thresholds. That gap should be below 10 %, so an individual has an excellent aerobic capacity and will not increase it much more.
  • I have seen this gap as low as 6 % in a World Cup cross-country skier. When we are talking about a base of 180 bpm, we reference a difference of only ten bpm. (narrow distance between them)
  • When an athlete has this high aerobic threshold, it would not be wise to do a lot of work near that aerobic threshold. It is too close to the anaerobic threshold. Even though they are in an aerobic metabolic state, it is very demanding on them neuromuscularly.
  • For example, Eluid Kipchoge competes at his aerobic threshold during the marathon. His aerobic pace is at 4:30 min/mile. Even if he is in an aerobic-predominant state at this pace, neuromuscularly running that fast takes a significant toll on the nervous system and the muscles.
  • If an athlete trains very much at that intensity, they will increase the likelihood of overtraining or injury. The fitter the athlete, the more polarised the training need to be.
  • The easy days need to be relatively easy so that the hard days can be more challenging.
  • Training much in the middle is a dangerous place for a fit athlete.
  • Someone aerobically deficient would need to work much close to that aerobic threshold.

Training zones

1:03:29 -

  • The athlete's needs are what should guide training.
  • It is one of the reasons that grabbing a training plan from someone from the internet does not make sense, and it is a huge mistake.
  • We will do what Kipchoge is doing because he is doing the training that he needs to improve and prepare.
  • If you are aerobic deficient, you will need to do completely different training.
  • Therefore, I like to start by establishing training zones with some forms of testing, so we need your metabolic response to exercise first.
  • Once we know that, we can start shaping the training around it.
  • We can have people with different aerobic capacities and need different training kinds.
  • It also means that training in a group can be dangerous. If I told two people with different aerobic capacities and told them to do the same training, they would get different training effects.
  • The strongest athletes might lead the pace in the correct training zone. For example, in a leisurely bike/run session, the ones at the front are training correctly, but those who do not have that aerobic fitness would be struggling. They would be in a higher training zone, not getting the desired training stimulus. These athletes risk becoming overtrained because they are doing the wrong kind of training stimulus too much.
  • Therefore, establishing a baseline to build from allows you to build a road map into the future.
  • After that, we can start sprinkling intensity when the athlete needs it, different for different athletes.
  • Moreover, there are many ways of adding intensity. A famous quote states: "It is not clear what kind of high-intensity training is the best stimulus."
  • Despite studies performed after that, we still do not know the best high-intensity type. And I believe that is the reason why there is so much variation.
  • Concerning base training, everyone understands how to do it. But we still do not know if it is better to do very short, high-intensity training or long duration "tempo training" around FTP.
  • Stephen Seiler accessed this in a study a few years ago, but the results show that it will depend on the athlete's needs.
  • If you tell a 17-years-old cross country skier to do 7-8 min as hard as they can, their speed and power will degrade so fast because they do not have to local endurance muscle to maintain that power output for that long.
  • If you ask a 28-year-old world-class cross-country skier to do the same, they will get tremendous benefits from doing the 4x8 type routine.
  • I think this is why you see so many different training philosophies. No one is sure about it, and therefore most coaches will try to do a bit of everything.
  • Eventually, you will find out which type you seem to respond best to when training.
  • Even if there are successful people with some training strategies, it does not mean that this will work for everybody.

Scott's rules for prescribing training

53:20 -

  • Every sickness is different, but in the initial phase of getting sick, you might have already a change in physiology before you realise you are not feeling well.
  • You can notice it in your morning and exercise data, where your HR is higher for the same intensity.
  • When you start to feel better after sickness, we do not have concrete evidence that your symptoms would be fading out before or after the data shows any changes.
  • It is also complicated to track even with Oura and other companies doing this work during covid. They tried to see differences at the beginning of the infection, but it is too difficult to find these reference points because you can have ten to fifteen different types of symptoms.
  • And you can also have these when you are healthy sometimes.
  • You have to check when you do not start to feel well, and defining this makes it challenging to do a systematic analysis.
  • If you have been sick for a couple of days and HRV has been low, you can use the data to understand when to return to regular training.
  • You can notice an HRV change to previous pre-sickness values when you recover. (you are returning to normal and can start training)

Different testing methods

1:14:37 -

  • Aerobic threshold testing is ground zero, and we need to do it before anything else because if you do not have enough aerobic capacity, nothing else will make a difference.
  • The cons of doing a VO2max test is that they pass through the low-intensity zones during tests (steps of 15s to 2-3 min) too fast. We only evaluate the maximum intensity you can sustain.
  • Therefore, they do not tire you of not reaching your maximum power. Sometimes, you can tell the aerobic threshold from that data, but it is not easy and becomes misleading.
  • You will quickly transition in that aerobic zone, and your aerobic system is slow to respond. If you do not have several minutes at that intensity, you will not have a good picture of this area.
  • You want a metabolic testing protocol that might take 45 to 60 minutes to complete.
  • Most people cannot do such an extended test and still produce their VO2max at the end of the test.
  • Another reason not to use VO2max to access your aerobic threshold is that you need to eat well, and your glycogen stores need to be full to produce your maximum aerobic power.
  • That glycogen is what you will need to produce that maximum power.
  • We ask people to do the aerobic threshold in a fasted state because we want to see how much energy athletes can produce from fat. If you go into a VO2max test in a fasted state, you will not see a VO2max.
  • These tests are different and expensive.
  • The lactate test is an excellent way to establish the aerobic threshold. You will measure the first significative rise in blood lactate to determine where that first lactate threshold occurs.
  • I do not use lactate testing as much now. I did it with skiers because I would test during training on the ground.
  • If you do lactate testing by yourself, you can do them wrongly.
  • Therefore, I usually do not recommend them to most people.
  • The ventilatory markers are straightforward to access the aerobic threshold (talk test).
  • The heart rate drift test shows a remarkable correlation between the accuracy of the heart rate drift compared to an excellent metabolic efficiency test or a gas exchange test.
  • I am pushing people more to do this test because you can administer it to yourself and access it more often.
  • Concerning the second threshold or the anaerobic threshold, I am not a fan of obtaining it either with a gas-exchange test or with a blood lactate test. You are transitioning through that zone in three minutes at the most.
  • I prefer those tests in the field as a time trial effort. For a world-class athlete, I usually use an effort of one hour in a sport's specific way.
  • In summer skiing, for cross-country skiers, they might be on roller skiers, and we have the average heart rate (in cross-country skiing, we do not have any other metric to measure effort) they could sustain for that hour.
  • In cycling, it is something similar, and you could do it by power (functional threshold power).
  • We measure an approximation for that intensity in lab tests while we measure the actual values in-field testing.

Setting zones based on test data

1:22:43 -

  • When I was competing in cross country skiing, the first Polar heart rate monitors came out. They were on your wrist, but they were big and clunky. But we were excited about the way to monitor intensity.
  • When they began to bring it to the US, we met with one representative from Polar. He said they created these training zones based on lactate values. Zone 1 was the point where your lactate should be at one mmol/L.
  • The top of Zone 2 was the point where you would have two mmoL/L of blood lactate. For Zone 3, it was the same, and Zone 4 was only hard. (anything above sustainable pace)
  • I started using that four-zone model ever since. I understand Stephen Seiler and the Norwegians use a three-zone model, which I think is excellent.
  • Dividing training zones into seven zones or something like that leads you to false precision.
  • Explaining to athletes the reasons for a zone being only ten watts wide is tricky because it is impossible to control intensity at that level when doing real training.
  • The training model's aerobic threshold would be at the top of Zone 2. The anaerobic threshold would be at the top of Zone 3.
  • Everything above that would be Zone 4.
  • I do not see much intensity use in Zone 5 or above.
  • The heart rate is not helpful because it does not respond as fast as needed. Moreover, it does not present the same correlations at lower levels of intensities.
  • If you are doing Zone 4 intervals of 4 min, heart rate will stabilise and indicate that intensity pretty quickly.
  • If you make 30s uphill running sprints, heart rate does not represent the effort.
  • For these short efforts, I tell people to go as hard as they can for those 30s; as such, you can repeat it repeatedly.
  • Zone 1 would be the recovery zone or where world-class aerobically fit athletes would spend the most time during training. The top of this zone is 10 % below the aerobic threshold.
  • I understand why it can be better to have more training zones to control the intensity.
  • If a runner is doing 800m repeats and know and control their pace, there is a big difference in doing it five seconds faster or slower.
  • It is silly to use more zones when you are a mountain athlete or a cross-country skier on undulating terrain and do not have those metrics.
  • If Zone 3 is only 8-10 bpm wide, it will be hard to control that intensity.

How to use different measurements of intensity

1:30:02 -

  • I wish we had a good way of measuring the intensity for the type of sports I coach.
  • Even heart rate is not an ideal proxy for the intensity, but it is the best for these sports.
  • I will measure effort if you have different measuring intensities like running pace or power on the bicycle.
  • If you are training for a triathlon, you can develop your aerobic and anaerobic threshold pace, and Jan's book is full of information on how to use that stuff.
  • You can use pace to measure intensity for swimming and running and power for the bike.
  • For triathlon, the ideal should be on determining those thresholds for each sport using one of the testing methods.
  • RPE is a crucial tool to understand, and athletes should not become overly data-driven.
  • It is excellent we can measure a lot of information about training, but in the end, I think it is essential to look at the data and have the same interest in the comments and subjective feedback on each effort from the athletes. While the data can look good, the athlete might feel tired. And the self-coached athlete needs to have a careful perception of the training effect the training is having on them.
  • "Training is not the work you do. It is the effect that work has on you."
  • It is essential not to depend on the training plan, so you have to reflect if the training is going in the right direction.

Rapid fire questions

1:36:23 -

What is your favourite book, blog or resource?

Special Strength Training: Manual for Coaches (chapter 7 will open your eyes to ideas for strength training) by Yuri Verkhoshansky

The Block Training System in Endurance Running by Yuri Verkhoshansky

(both available on Amazon)

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

Scepticism and curiosity.

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

 David Rudisha is someone that inspires me on the sports side.


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.

  • Great episode, Mikael! You mentioned in the podcast an recent website for calculating aerobic threshold from existing lactate data, but I did not see it in the show notes….thought you might have said “xfitlab” or the like, but not sure. Any clarification would be helpful, thank you!

  • this is long time waiting episode. I am xc skier and I was looking for some specific training tips and techniques for “uphill” athletes.

  • I enjoyed this discussion, thank you. I was surprised to hear: “you can only increase the aerobic capacity from below…If you train above it, it will not increase that aerobic base. It would push it down.” I have always thought that training above would still increase aerobic capacity but at the cost of lower training volume. I admit that intuitively, I still don’t understand how being slightly or moderately above first threshold would dysregulate the aerobic pathways and training of aerobic metabolism. I would have guessed the aerobic pathway is still being stressed/trained even as the anaerobic action begins to phase in. If you could expand on the physiology of this in a future episode, that would be great! Thank you for a wonderful podcast!

    • I was confused by this too. Above the aerobic threshold the anaerobic contribution starts to dominate but the aerobic contribution is still high and increasing. My rationalisation would be to factor in muscle fibre types. If you go above the aerobic threshold you start to use more fast twitch muscle fibres which produce lactate through glycolysis. Whereas you want to be training the slow twitch fibres which are the muscle fibres which are good at using up lactate. As in the ‘hoover’ analogy. I think if you try to train aerobic capacity from above then you do not stress the slow twitch fibres to the same degree and do not build a big enough ‘hoover’. If I am on the right line I would love to know?

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