Physiology, Podcast, Training

Anybody can be a Kona qualifier: genetics is not your limiter with Alan Cozens | EP#186

 June 17, 2019

By  Mikael Eriksson

Anybody can be a Kona qualifier: genetics is not your limiter with Alan Couzens | EP#186

TTS186 - Anybody can be a Kona qualifier_ genetics is not your limiter with Alan Cozens

Alan Couzens is a coach and exercise physiologist in Boulder, Colorado. Through his laboratory testing of a large number of athletes over a long time period he has found that triathlon and endurance sports potential (specifically VO2max) is far more trainable and less limited by genetics than what most textbooks and university courses would have us believe. In fact, most triathletes may actually have the potential to qualify for Kona - with the right training.

Discuss this episode!

  • Let's discuss this episode and the topic in general. Post any comments or questions in the comments at the bottom of the shownotes. Join the discussion here!

In this Episode you'll learn about:

  • How trainable is VO2max really?
  • Why do most athletes fail to reach their athletic potential even though they are putting in a lot of hard work?
  • What is the right way to train to reach your athletic potential?
  • The importance of training at the first lactate/ventilatory threshold (aerobic threshold). 
  • The importance of proper testing so you can do the right testing for you.
  • When to use heart rate vs. pace/power in training. 

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About Alan Couzens

5:30 -

  • I am primarily a coach, I have a background in exercise physiology.
  • I spent a good portion of the last couple of decades testing athletes, with a focus on endurance athletes and long course triathletes. 
  • I've been in Boulder for the past 15 years, which has given me some good access to high level triathletes.

    I've had the good fortune to test some of the best athletes in the world. 
  • I have now moved more into the coaching and consulting domain. 

What is VO2max and why is it important?

7:04 -

  • VO2max is the maximal rate of oxygen uptake by the muscles. 
  • It's often express relative to body weight - ml/kg/minute. 
  • It's very important because it's a good general indicator of everything that goes on within the aerobic system. 

    We've got both central aspects, where there's a component related to how much cardiac output is being put out by the heart.

    There's also a muscle aspect to it - the ability of the muscles to extract oxygen from the blood that they're receiving. 
  • When an athlete has a high VO2max we know they have a really strong central system and the ability to get a lot of oxygen to the muscles, and also a strong ability within the muscles to get oxygen out of the blood they receive. 

    This means their aerobic power is very high. 
  • For all the events you do as a triathlete, they're all aerobically dominant.

    Anything belong a minute duration is reliant on energy production from the aerobic system. 

VO2max benchmarks 

9:05 -

  • World class levels are in the range of 75-85ml/kg for men, for more of the short course athletes. 

    Generally about 10ml/kg less for females. 
  • Most of us will be seeing 55-60 on our Garmin which shows how strong the aerobic system is in world class athletes!
  • Ironman athletes are a bit lower than short course athletes in my experience, more in the range of 70-80ml/kg for the males, 60-70 for the females. 
  • Kona qualified type athletes you're starting to get down a bit below that - probably the 65-70 range for males. 
  • Average for middle of the pack recreational athlete would be 50-60 range for males, 40-50 for females. 
  • The rate of decline with age is very different depending on whether you're a life long trained athlete, compared to either a sedentary athlete or an athlete that was serious but then retired. 

    There's been a lot of studies that have shown in athletes that train over the course of their entire life the drop in VO2max per decade can be as low as 5%. 

    When we see 70-75 year old athletes who still have a VO2max higher than an untrained 20 year old it gives an indication of just what a potent stimulus exercise over the entire lifespan is!
  • Typically there is a bit of a gap between bike and run - it depends a little bit on the size of the athlete. 

    Athletes who are larger will tend to be able to narrow the gap more than smaller, lighter athletes. 

    Somewhere in the range of 5-10% would be a typical gap (with the running being higher) I'd see when bike and run testing the same athlete.
  • In swimming we have done some VO2max testing when I was at the institute of sport but typically it's not really done. 
  • The swim values are interesting because swimmers would be an example where they tend to get by with a lower VO2max than other sports, purely because of the muscle mass involved in swimming versus running and cycling. 

How trainable is VO2max?

13:33 -

  • In my undergraduate degree it was drilled into us that VO2max is largely genetically determined and at best you can expect to increase it by 5-15%.

    But my experience hasn't gelled with this at all!
  • The research it was based on was a lot of short term studies, including one by Jack Daniels that is often cited.

    It was an 8-week study that showed a big increase in untrained athletes VO2max in the first 4 weeks, and then a plateau after that.

    That pattern has been replicated again and again in short term studies.
  • I think because a lot of studies are limited to short time spans we don't see the pattern beyond that, and that is responsible to the rule of thumb that you'll get close to your maximal potential in a short amount of time and then it won't go up. 
  • The article I did was a case study of an athlete I worked with over 3 years.

    He came in as a very 'normal' athlete, middle of the pack. 
  • We tested him and his initial VO2max was 53ml/kg, right in the average range for someone who is relatively fit but no indication he could become elite based on that measurement. 
  • Over the course of 3 years he increased his VO2max from 53ml/kg to 74ml/kg.

    74 is starting to get up to a fairly elite level of performance - and it was a bump of 40% over three years. 
  • We tested a couple of times per season to it's hard to discern how quickly the improvement was. 

    I've had other athletes that I've tested more frequently and we do definitely see the large increase, particularly if we're doing a high intensity cycle in  a short period of time. 
  • This adds confusion because there is almost two types of increase: 

    The type you get from short duration, high intensity training. 
    The type long steady grinding increase that you get from the volume. 
  • We see that when we do a high intensity block you get a boost, but it always plateaus out because it's not sustainable in the long term. 

Training to increase VO2max

19:42 - 

  • The big confusion point often comes from the fact athletes think they have to train at a certain point to improve that point.
  • With VO2max, it's a composite of a lot of different things going on within the aerobic system - oxygen delivery, oxygen extraction from the muscles - and all fibres are helping out.
  • My perspective is that the training we do to increase all the variables - economy for athlete, threshold, etc - the right training leads to improvements in each of the aerobic system elements to a varying degree.
  • When we're doing a lot of low intensity training around the first aerobic threshold, we're not only improving the threshold but also all points north of that - which includes VO2max. 
  • For the athlete in the case study, his fat burning was not a strength initially, and I place a lot of importance on this. 

    So we spent a lot of the initial period over the first couple of years really focusing on increasing his metabolic strength and fat burning capacity. 

    His goals were long course, Ironman specifically, so we did a lot of training around that first aerobic threshold. 
  • It was interesting to see just how much training that was designed to increase his VO2max actually did so vicariously. 
  • For this athlete we were doing 8/10 sessions per week at the aerobic threshold, and a couple of speed maintenance sessions. 

    It was a lot of volume, heart rate usually at 120-135bmp. 

    This continued essentially for the first two years, and he had impressive improvements in fat burning from this.
  • There is a pattern of athletes who come from a high intensity programme, and when they get tested the metabolic side of things is generally the least impressive. 

    Even with athletes who have a good VO2max, if it's been from extended periods of sweet spot or high intensity training the metabolic system is negatively affected. 

Typical VO2max improvements in 'normal' cases

26:33 - 

  • When I was putting together the case study I pulled all my data down from all athletes I'd worked with over multi-month periods and built a linear model to see what the average VO2max increase was over a 3 year period. 
  • The case study athlete I mentioned went 40%, but the average from all athletes was 24%.

    This is still significantly greater than that 15% lifetime improvement that is often quoted. 
  • A lot of these athletes aren't in the same shape when they come to me as the case study athlete was. 

    Typically they are fairly good - and if you're coming with a VO2max of 60-65, to see a 40% increase on that would be slightly unrealistic. 

    So we might not see the same percentage jump if athletes have already eked out a good amount of their potential improvement. 
  • I think most athletes physiologically have the ability to get to Kona qualifying fitness.

    Given the right training over a sufficient period of time, most athletes are able to reach the 65-70ml/kg range. 
  • If you're putting in more than 1000 hours a year and you're not qualifying for Kona, that would be rare. 

Training volume needed to improve VO2max 

31:48 - 

  • There's a paradigm at the moment that is largely bourn out of the TSS obsession that more load = better performance. 

    It's important to tear that apart a little, and let people know it's not the load that will lead to performance, it's the right balance of different training and energy systems. 
  • For a lot of athletes, they get in the mindset that if they can't do volume they're going to do intensity, but it shouldn't be an either or. 

    There's the right intensities that are going to each add a certain element to your physiology, and then there's the volume you can do within the context of your greater life. 

    These factors ultimately determine where your fitness reaches. 
  • Stephen Seiler did a good study that spoke to this looking at recreational athletes training 8 hours per week.

    The amount of zone 2 time for the high intensity group went up to 40% of total volume, whereas the low intensity volume only did a small amount in Seiler zone 2. 

    All that extra effort and mid-range sweet sport work that the zone 2 group did, did not equate to any improvement in performance. 
  • Cranking up the intensity doesn't mean you'll have a big performance boost.
  • If you want to go to Kona, the typical yearly training hours is probably 800 hours on average. 

    It is around 16 hours a week, but it'll fluctuate throughout the year - in the early season it may be 10-12 hours, but in the late season there may be some 20+ hour weeks. 
  • I've worked with athletes who are well below though - the proverbial 'get to Kona on 10 hours a week' athletes, but they won the genetic lottery. 

    I've also worked with the other side of the equation - athletes who have had to put in more than 1000 hours a year to get to that level of performance. 

    There is a wide range in training response. 
  • Consistency is key - 16 hours per week doesn't sound too hard but it's about doing this consistently throughout a whole season. 

How to use high intensity training

38:29 - 

  • One of the big influences on my view of high intensity training was an Australian swim coach called John Carew. 

    He was the coach of Kieren Perkins, a multiple Olympic champion and record holder in the 1500m. 

    He was big on heart rate training so all his high intensity training sets were done to given heart rates. 

    For Kieren, most of these heart rate ranges topped out around threshold, but he would do short duration - e.g. sets of 100's with 30 seconds rest.

    So the pace may be VO2max but the demand of the session with a threshold level.
  • I tend to favour that approach for most of the year - we will do some fast workouts but generally, from a metabolic or total stress perspective, the heart rate doesn't reach very high levels. 

    We control the work/rest ratio to keep it in and around the threshold level, which sometimes means doing quite short intervals. 
  • For very short events there is probably a period of sharpening, where you'll do longer intervals that have significant lactate accumulation. 
  • For long distance athletes, those sort of intervals that don't create a lot of stress and you can maintain week after week do enough to preserve the top end. 

    This is important for the long term development of the athlete as we want to stay in touch with those fibres. 
  • We've done lactate measurements during those sessions and it's typically a 4mmol session - it's very much threshold in both lactate and heart rate. 

    There's not a lot of acidosis or central demand, it doesn't tire the athlete out like a session of 10 x 1km would on the track.
  • It's a high value with relatively low risk way of approaching speed work. 
  • The two high intensity sessions I'd prescribe would usually be a speed session and then something more in the moderate range - often big gear/high resistance sweet spot work.
  • If I had an athlete where I was trying to significantly improve their specific endurance we might pay more attention to moderate, sweet spot sessions.

    Vice versa would apply, if we have an athlete very good at grinding it out but has a hard time accessing the top end, we'd cut back on the sweet spot sessions and increase emphasis on speed work. 

Low intensity training & recovery

44:43 - 

  • The bulk of the training sessions that I prescribe are in and around the aerobic threshold, plus or minus 5-10 beats either side. 
  • Recovery sessions serve an important point to get the benefit from the training. 

    I don't see those sessions as training themselves, but by doing recovery work you can more bang for your buck from the work. 

Training execution & training zones 

46:02 -

  • Typically the first part of the season will always be heart rate based. 
  • Over time as you progress to the A race we'll start doing more power and pace work, generally revolving round the goal pace for the race. 

    In the beginning that might be sweet spot sessions for the Ironman athlete because we're expecting their fitness to increase over those months. 
  • I'm a big fan of insisting athletes get regular testing done. 

    We then use the zones we get out of testing, whether lactate or metabolic. 
  • We test multiple times per year as I think the data is essential for setting appropriate zones. 
  • The most important one I'm interested in is seeing where that aerobic threshold is on the curve.

    A lot of the sessions will be in an around this point so I want to see how it's shifting over time. 

    The zones we use will be very much centred on where that point is on the lactate curve. 
  • The second threshold is obviously important too, because we want to be able to prescribe the right intensity for sustained aerobic work. 
  • With swimming it's more challenging to test. For athletes that I have physical access to we would still do lactate testing - you just need to keep the ear lobe under the cap and spike it every few 100m's! 
  • For athlete who are remote we have to approximate more and use general zones. 
  • If you at least have an idea what the athletes lactate curve looks like you get a sense of what type of athlete they are, and you are then generally able to dial in the percentages a little better. 

Swim training 

50:35 - 

  • For a lot of athletes, they're always training at anaerobic threshold or close to it on the swim.

    Often this is not intentional and may be due to a lack of technical ability. 
  • Getting the athlete able to swim at very low efforts, and having the technical ability to do that, is really important. 

    This can often involve getting the breathing dialled in so they don't expend a lot of energy taking a breath. 
  • This gives the athlete access to lower ranges of outputs so we can start to do more threshold work. 
  • Without that ability, no matter what you do you'll be in Seiler zone 2, or Friel zone 3-4 range when they swim. 
  • Tools can become a bit of a crutch - it's important to develop the ability to swim easy and not have a high heart rate when you're doing that. 
  • We use heart rate in the swim, and do a heart rate test every block. 

    I want to know what pace they're at for their low intensity heart rate and their 'close to threshold' heart rate. 

    I can then get a sense of how those things relate, which tells me a lot about the type of swimmer that they are - whether they're technically proficient at low intensity or more of a one gear swimmer. 
  • These swim measurements are particularly important in a race situation as athletes often typically underestimate their heart rate by 20-30 beats.

    It can be helpful to look back after the race and see just how high the heart rate was in the water. 
  • It's just so important to get into the lab and get this data, we can approximate it but nothing beats getting into the lab, seeing what metrics you're at, then reassessing after training to see the improvements! 

Key takeaway

  • Patience is vital - stick to the plan and follow through with great discipline. 
  • There's no shortcut, if you did not win the genetic lottery you can still get very competitive but you need to put in the work. 

    Also look at your training year, not just the week. 
  • Proper testing takes much of the guess work out of the planning process and finding what training is right for you. 

Links, resources and contact

Links and resources mentioned

    Connect with Alan Couzens

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  • Alan says: “The bulk of the training sessions that I prescribe are in and around the aerobic threshold, plus or minus 5-10 beats either side.”

    This seems like an incredibly hard training. Your marathon race pace is at VT1, so if you train at this pace it’s very taxing especially if you
    have good aerobic endurance (your pace at VT1 will be pretty fast

    Also, if the spread between VT1 and VT2 is small (for trained athletes less than 10%), you can be pretty quickly training in the middle of the VT1/VT2 zone.

    • I agree that for well-trained athletes this seems very hard. I don’t want to put words in the mouth of Alan, but my interpretation would be that the more trained you are, the more you skew towards the minus 5-10 beats side, and also the more you will have pure recovery sessions so it’s not just LT1/VT1 sessions.

      Erring on the side of minus 5-10 bpm also ensures that you avoid that mid-zone between VT1 and VT2.

      This is pretty much how I approach things and also how I would interpret the interview.

  • Thank you for a great episode with an interesting subject!

    I am wondering if you have some thoughts about how long duration the low intensity sessions has to be to be of any use? I typically do my long rides / runs at or below the first aerobic threshold point with duration of 2 hours and more. But would for instance two sessions of 1 hour at low intensity be just as good as one session of 2 hours, or does it require some length to be productive?

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