Gear & Technology, Podcast, Science and Physiology, Training

Training, tech and physiology with Mikael Eriksson and Matthew DesRoches | EP#352

 August 22, 2022

By  Bernardo Gonçalves


Mikael Eriksson and Matthew Desroches - That Triathlon Show

This is a conversation between Mikael Eriksson and Matthew DesRoches (of Recilience Health and Performance Consulting) that originally aired on Matthew's podcast Oxidative Potential.

In this episode you'll learn about:

  • Power-duration modelling, lab testing, and software-based physiological testing
  • Training monitoring
  • A different approach to swim training
  • Revisiting the fundamentals of exercise physiology
  • Technology and diagnostic tools

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Finding the balance between interviewing coaches and researchers

04:25 -

  • It is a complex balance because it is challenging to find good quality coaches as there are always new PhD researchers.
  • Not many coaches have a decent understanding of physiology and coaching experience.
  • Due to time constraints, most coaches create a system that will remain the same for the career.

Mikael's background

06:16 -

  • I did my first marathon when I was 17, but my primary sport when growing up was football. When I started university, I started running recreationally, doing a marathon every couple of months.
  • Every time I did a marathon, I got a bit faster, excited to pursue getting faster, and started reading a lot.
  • The books of authors like Jack Daniels got me into the world of running and started coaching as well.
  • I got injured from running and started cycling and swimming as cross training.
  • I always thought that I would start doing triathlons at some point. 
  • During this period, when I was injured, I would only train for triathlons, and once I got to run with no pain again, I was hooked to the triathlon scene.
  • The challenge of doing three sports is exciting, and there are more things to consider. I kept learning about endurance sports but in the triathlon space.
  • It did not take long to start coaching on a small scale.
  • I got injured while graduating from university and worked in medical engineering. I started coaching alongside that as a sidekick.
  • Eventually, I decided I truly enjoyed it and wanted to get better at coaching. I could only commit myself to it if I quit my job and took a leap of faith.
  • That was in 2017, so I have been coaching full-time for five years, and at the same time, I started the podcast "That Triathlon Show".

Mikael's perspective on the triathlon culture when he started doing triathlons

11:25 -

  • In triathlon, there is a significant focus on metrics and data. However, this trend varies in each country.
  • For example, in Finland, you have a triathlon scene with primarily age groupers. Whereas in Portugal, you have young athletes doing triathlons, which is a thing that you do not see in Finland.
  • That aspect brings a different culture to triathlon. People had grown up doing triathlons when they did not know what pace or power was.
  • Therefore, there might be less focus on data, which might be a good thing. 
  • Moreover, triathletes are meticulous at training and preparing things. They take their sport seriously, which is good if the goal is performance.
  • Also, triathletes like to experiment and have an open mind on different topics, which is fantastic. Sometimes, it backfires, but you have to filter those experiments.

Power duration modelling and its application in training

15:54 -

  • This concept of power duration modelling comes from the 80s in Germany (Mader's studies). It constitutes how VO2max and VLamax act as controls that their interaction determines things like MLSS and other critical parameters for endurance performance.
  • If you know VO2max and VLamax, you can figure out your physiological parameters. (characterisation of your whole physiology based on some capacity parameters)
  • I had used both INSCYD and Aerotune in the past, but I stopped doing it last year.
  • A pre-printed review analysed this topic and attempted to validate the model.
  • They concluded that for running, the model does not seem to work with running. In cycling, the errors lead to authors not recommending the use of these models.
  • For example, when measuring VLamax, you are measuring capillary lactate concentration, but the model talks about the lactate concentration in the muscle. The measurements we do are not the ones proposed in the model.
  • Moreover, there are some assumptions not validated yet in the literature.
  • I stopped doing them because when comparing athletes that did testing with those that would not do testing, I would not find any difference and no help from those tests.
  • I do use critical power and power duration modelling, and I think there is value in those concepts.
  • And we can do the same analysis with critical power without going into a lab.

Monitoring training intervention and response

22:07 -

  • First, I look at the data from workouts and tests. During the training block, we are trying to bridge some gaps in the athlete's performance. For example, work towards a power racing target and see that athletes can hold higher power outputs or extend that power for more extended durations.
  • Conversations with athletes help me understand how they perceive their improvement and performance during training. (workout comments and RPE go along with that subjective feedback)
  • The red flags to pull back on training appear when we have negative comments or discussions with the athletes concerning training.
  • Of course, one workout does not tell us a lot because it could have been only a "bad day".
  • If we see athletes getting negative comments, that will turn in some changes in training.
  • I used HRV for some time, but for example, I stopped measuring it personally, and I do not require my athletes to measure it, although I encourage it.
  • HRV might be slightly overhyped because it measures the state of the autonomic system (balance between sympathetic and parasympathetic). Still, there are so many more things that can go wrong when looking for red flags.
  • Not every flat will pop up with an HRV variation, and some coaches and athletes believe that if HRV is good, everything is ok.
  • Most well-trained athletes are very fit aerobically. In these cases, HRV is exceptionally stable.
  • If you get sick, you see changes but do not see considerable fluctuations in HRV in most training blocks.
  • Moreover, there are many nuances to measuring HRV consistently, so its application might be highly individual.
  • I also want to point out from HRV studies that you cannot blind participants from what they are doing.
  • HRV-guided groups know they are training according to it, which could induce a placebo effect, which could be the reason for a positive benefit of HRV-guided training.
  • For example, athletes that measure HRV daily might suffer psychological effects from having a lower HRV reading. (even if it is only an artefact)

Concepts or topics Mikael is excited about at the moment

36:06 -

  • I am excited about swim training in a triathlon context.
  • Although I am not the first to come up with this, it is something that has grown in me, and now I am testing it out.
  • The concept is to train more the swim as you would with the bike or run.
  • We have a strong influence from traditional swim training, meaning you do sets with lots of "bells and whistles". (there are too many things going on)
  • We do too many drills despite not knowing why we are doing them with different intervals and speeds.
  • Of course, swimming is a technical sport, so developing your swimming technique should be a top priority.
  • Some athletes have a decent technique, so this aspect is not their limitation.
  • Most athletes do not swim better because of our swim training methods. 
  • In triathlon swimming, we see what swimmers are doing and copy them because we think that might be the best approach.
  • However, triathletes have much less time to swim, and our preparation is not as good as the swimmers.
  • So, my approach is to do more long endurance swimming. Often you see athletes doing an endurance swim, but they do 30x100m, and some do an acceleration to make it fun.
  • Therefore, you might swim for 1min20, rest for 15-20s and then go again. However, you would not do a bike or run workout like that if the goal is aerobic swimming development.
  • So, I am experimenting with 8x400m or 6x600m. They are boring, but swimming is an endurance sport, and endurance sports are monotonous.
  • Moreover, I think we are doing the intense part of the swim at too high intensities.
  • Therefore, I started doing some lactate testing in the pool.
  • For example, a typical set might be 15x100m at threshold with a 15s break. So, in time, this would be 15x1min20s (with 15s of rest). If we work like this, the work-to-rest ratio is like 6:1, which is high compared to what you would do on the bike or the run.
  • So, I am doing longer intervals, so the intensity is more controlled. If you do group swims and do that 15x100 m, you will do them as fast as possible.
  • While I think group swims are valuable but there are also some caveats. This threshold workout can become a VO2max session with very short recoveries, and some athletes will become tired for the rest of the day.
  • It is not a surprise because they did a workout with a lot of anaerobic contribution.
  • Therefore, I redesign the workout to do longer intervals to make it difficult for athletes to go too hard, but I also have the pace prescription correct from the start.
  • For example, I could increase the workout to 12x200m, making the workload higher but also increasing rest periods. I still do only 45-1min rest periods, probably because of the typical swim workout bias.
  • Typically, the threshold is the pace you can hold for 30min. So, I have some athletes doing 1900m time trials, which is the 70.3 swim distance, so it takes 25-30min for a relatively quick swimmer. And that would be the threshold I would use for training prescription.
  • We force athletes to swim slower with the longer endurance reps (4-5x800m). Moreover, the rest is more mental than physical. On a bike ride, you would only stop if you had to do it.
  • People tend to swim at too high an intensity. While it might work with some people, it only works with those athletes that can tolerate a high training load. However, for most people, I think it is too much.
  • In defence of swimming coaches, swimming events are short, so finding physiological thresholds does not matter as much.
  • So, that is why I think coaches do not consider so much physiology on the swim.
  • However, as triathletes, we swim for much longer and have to run and bike after those efforts.

How Mikael would coach himself

55:13 -

  • The first thing I would do is to understand the importance of enjoying the process, consistency and the primary objective to stay healthy and injury free.
  • That way, I would do much less running than I did in my early 20s.
  • If I had the talent to step up, I would focus on skills, speed and power in those early years. However, I do not mean many anaerobic workouts. So, doing training races and short races. (super sprint races)
  • I would keep track of volume carefully. 
  • As I got older, I would emphasise the threshold work.
  • Once I got to the last year of under 23, my VO2max would probably reach the maximum it would reach. At that point, I would transition to focusing on doing threshold work more than I did before.
  • Also, the volume would increase to a specific point. You are at your peak volume when you are 23-25 years old, but probably not before that.
  • Therefore, your aerobic capacity would go up as your economy.
  • When I was 16, there was no training group I could join to do organic workouts, where you go out and ride your bike to learn how to ride in a group and corner well.
  • There was not that type of environment for young triathletes in Finland. However, here in Portugal, there is that environment.
  • Sometimes, you must be careful with training, but you do not need to individualise training too much at that age.

How Mikael uses his "toolbox" to work with athletes

1:04:50 -

  • It all comes down to the athlete's goals and comparing where they are currently to where they want to go.
  • We do a gap analysis, and we figure out that if you have a one-minute deficit on the swim but a 15 min deficit on the bike and a 30 min on the run, I would say to keep the swim as it is because we need to improve the bike and the run.
  • Moreover, the run and bike are typically connected. If you get fitter on the bike, running close to your potential off the bike is more manageable.
  • So, you must understand how much more power you need to put into riding 15 minutes faster or if you can gain that time with aerodynamic improvements. You consider your options and will probably be a combination of the two.
  • We improve your bike split, which means you can ride more comfortably. Therefore, you will probably improve your run split.
  • You might also look at nutrition and hydration.
  • In conclusion, it is a long checklist of things you must go through of what the things you need to work on are.
  • Of course, you cannot work on everything, so you may choose to work on 2-4 things.
  • In many cases, you will not need specific testing because there is information on the past races and athletes' efforts.
  • For example, we might work on the threshold and know precisely what intensity we should work on, even though we do not do any testing.
  • However, there might be cases where you are unsure of where you are. For example, understanding the percentage of VO2max you are working at when doing threshold intervals could help you understand the type of work you should be doing.

Piece of technology that Mikael would add with athletes

1:11:08 -

  • Continuous non-invasive lactate measurement would be something quite interesting to have.
  • However, I would say that if all my athletes had a lactate meter and the capacity to test themselves, it would be great.
  • I also would consider RMS to check muscle typology because I used to work in this field.
  • I think this could have a significant impact on training decisions and training responses as well.

Preconceived notions Mikael had that led to failure

1:15:37 -

  • Sometimes, helping athletes with paces in my early coaching would not go well.
  • This point came from what I thought would be the norm (what athletes should hold a specific pace for a specific race).
  • For example, if you search for the optimal intensity for racing an Olympic triathlon, the numbers are primarily for professional or advanced athletes.

Test that Mikael would use above all others to work with athletes

1:18:48 -

  • I guess it depends a bit on the athlete. 
  • I would say doing a couple of time trials to build a power/duration curve.
  • Or I could prescribe all-out efforts on the workouts and get the power/duration curve without calling it a test.
  • If I did that, I would have a lactate test to identify LT1.
  • However, most athletes I coach do not use it. If you know your pace and are well trained, it is easy to train in the correct zones.
  • In some cases, if you want to train close to that point, I find some scenarios helpful to know in more detail.

Different Areas Mikael focuses outside of sports

1:22:11 -

  • Five years ago, I had much expertise in medical devices, both in RMIs and transcranial electrical stimulation.
  • I also have other interests. I still follow English football (Premier League), but it is not something I do purposefully.
  • I also listen to many audiobooks and am interested in understanding how the world works.
  • I am listening to some audiobooks on the geopolitics realms.


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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