Jordan Santos, associate professor, discusses a number of topics within running science and their practical implications for triathletes. 

• Lactate testing best practices, validity of field testing to estimate lactate threshold, and using heart rate variability to estimate lactate threshold in the near future? 
• Running economy: how important is it and how can it be improved? 
• Strength training for running and its impact on performance. 
• The best predictors of running performance. 

0:35 - 

• Jordan is an associate professor at the University of Basque Country in Spain
• Jordan has conducted and supervised research in the variety of areas covered in today's podcast.
• In addition to his knowledge about the science of running, Jordan is a very good athlete himself.
• He has worked with Professor Tim Noakes and Dr Ross Tucker - two of the most famous sports scientists in the world.
  • This was when he worked as a post-doctoral research fellow at the University of Cape Town.

4:44 -

• Lactate threshold is one of the main physiological determinants of performance, together with running economy and VO2max.
• I try to understand which lactate threshold method is the best one to adequately measure running performance in runners of different levels.
• We have many strategies to measure lactate threshold these days, and every one has a different meaning.
  • Even if it's a small difference between methods, we may not calculate the exact data point that we want for our training plans.
• I am conducting research to see which equation is the best for lactate threshold determination, the ideal length of the workload and ideal recovery etc.
• The main problem with the incremental maximal test to determine ventilatory thresholds is that, in my opinion, the results are highly unreliable.
  • We need a gas analyser to determine them, and many runners feel a lot of discomfort during these tests.
  • Sometimes the results you get doing this on a treadmill are not great.
• I prefer the classic lactate tests on a track.
• The gold standard is the maximal lactate steady state method.
  • However you need 3-4 training sessions to determine this factor.
• I am trying to work on the best strategy to determine lactate threshold using only one training session.
• For what I've seen, the best method is the Dmax Strategy.
  • This is not the easiest to calculate but it's the most reliable.
  • During the session you have to do at least 6 workloads.
    • The initial workload lasts around 3 minutes, or you can use 3 laps (~1200m) on a track.
    • The initial intensity is around 50% of VO2max.
    • You have 20 seconds of recovery between each workload, and you incrementally increase the pace by 10%.
    • I.e. the second workload will be 60% of VO2max, the next will be 70% etc.
    • You complete 6 workloads with this incremental increase and you end up with good data points.
  • Using the data points, you can calculate the lactate threshold using different techniques.
    • I prefer the Dmax method.
• The Dmax method is already published.
• Once you get your 6 data points, you can perform a regression equation.
  • You can use two different regressions:
    • Polynomial regression is the most typical and easiest to understand
    • Exponential regression is more reliable because it doesn't get affect as much by the initial intensity, but it is complex to calculate and it's not easy to understand.

• You have to go to Excel and insert the data points. From here you can use Excel to calculate a regression line and you can select polynomial regression.
  • This gives you a lactate curve, and you then have to calculate the lactate threshold.
  • If you use the D-Max method you draw a straight line from the first point to the last one, and see what the maximal distance between that line and the curve you calculated.
  • The maximal difference will be the lactate threshold.
    
• I compared this test to the onset of lactate accumulation test, which corresponds to 4mmol of lactate.
  • Many athletes still use the 4mmol of lactate as an indicator.
  • However, we have seen that this is not the same for every athlete, so I wouldn't recommend the use of this test to estimate training intensities.
• Conducting field tests (e.g. estimating lactate threshold pace based on a 20-minute test) is not the most reliable strategy, but a lot of people don't have access to a lactate analyser.
  • For people with no resources this can be a good enough strategy.
• We have compared the results you get from a field test to what you get using lactate testing equipment and found the differences differ depending on athletes.
  • For some athletes, the 20-minute test underestimates the lactate threshold, but for others it overestimates it.
  • The error can be around 5%.
• If we are training elite level athletes we have to individualise the training plans perfectly, and a 5% difference to the real lactate threshold may imply that the athlete is training too hard and the risk of over-training is there.
  • For elite athletes I always recommend proper lactate testing equipment.

13:05 - 

• I worked on this topic as part of a project for a PhD student of mine called Mark Kennealy who was an Olympic marathon runner in 2012.
• He wanted to focus on training intensity distribution and is trying to see whether different periodisations are better for runners or not.
• At the moment, most runners use either the pyramidal or the polarised training intensity distributions.
• But we've seen that most of the best athletes in the world use the threshold periodisation.
• We are trying to basically unravel what's going on here - trying to see why the best athletes in the world (i.e. Kenyan's) are using threshold periodisation.
  • According to the scientific literature this periodisation is not the best.
  • We're trying to see why it works for them when studies say it's not the best method.
• Hopefully, in a few months we will have an answer!
• So far we've done a literature review published in the International Journal of Sports Physiology and Performance.
• At the moment, we are working with a team of elite endurance runners from Australia.
  • We are also working closely with an Australian coach called Nic Bideau who works with the best middle and lost distance runners in Australia.
  • We have tons of data but we haven't analysed it yet!
• In terms of the models, when we talk about periodisation we're discussing how we distribute the different training intensities.
• The difference between the three main models is how much time is spent at each intensity:
  • The polarised model involves spending a lot of volume at low intensities (far below lactate threshold), and a lot of volume at zone 3 (higher than lactate threshold). Less volume will be spent at zone 2 (lactate threshold).
  • The threshold model involves training a lot in zone 1 and zone 2, but less in zone 3.
  • The pyramidal model involves spending a lot of training volume in zone 1, a little bit less in zone 2, and a little bit less still in zone 3.
• For listeners who are used to 5-zone systems (or other versions), in scientific literature, training zones are typically often simplified and only three zones are used.
  • The first threshold (aerobic) is the border of zone 1 and 2, and the second threshold (lactate, anaerobic) is the border of zones 2 and 3.

16:50 - 

• Running economy is one of the main determinants of endurance performance.
• It has received a lot of attention in the last decade, and we've seen you can predict whether a runner is good or not based only on running economy.
• Running economy is the amount of oxygen or energy needed to cover a set distance.
  • Usually it's 1km.
• We have seen that elite Kenyan and other African athletes are more economical and efficient than European athletes of similar profiles.
• With running economy there is a huge margin of improvement.
  • Similar to other physiological determinants of performance, running economy can be improved with training.
• There are many ways to improve running economy, such as:
  • Improving your biomechanical technique.
    • If you have a bad technique (e.g. over-stride, or heel striking), by changing it you can improve your running economy, become more efficient and perform better.
  • Including proper strength training into plans.
    • This may dramatically improve running economy.
    • You can improve performance without affecting your VO2max or running threshold.
    • The improvements, according to the literature, can be close to 10%, particularly for recreational runners.
    • Strength training makes you stronger and able to tolerate higher training volumes.
    • It also helps reduce your risk of injury, increase efficiency and help you run faster.
• Running is not just going out to the park and doing a long run.
  • To be an elite runner you need to go to the gym and lift heavy.
• We've seen that the best strength training is doing heavy lifts, at the maximum speed you can move.
• I encourage every runner to try to level up their strength training and include 2 sessions a week to see real improvements.
• With strength training you need to work at low reps (4-5 reps) and that will be around 80% of 1-rep max.
• Go for the basic exercises such as bench press, squats, hip thrusts, dead lifts, lunges etc.

• Plyometrics, such as drop jumps or multi-jumps, can increase the stiffness of tendons.
  • This will also improve running economy and efficiency.
  • You improve the body's ability to release elastic energy out of the tendons so you can run the same speed but expend less energy.
• Plyometrics are great but they're not for everybody.
  • For an elite or middle distance runner they're fine.
  • For recreational runners, if you don't have a good technique or somebody supervising the exercises, you might be at risk of an injury.
• Progression is recommended, starting with steady lifts at the beginning of the season and moving into more explosive strength training.
  • E.g. including Olympic weightlifting such as cleans, and then including plyometrics closer to race season.
• The complication for triathletes is that the same applies in terms of heavy weights/low reps, but the explosive components isn't as helpful for cycling.
• For a runner, it's great to have a huge stiffness, but this might impair your performance in swimming.
• In triathlon, in order to be really successful the most important part is probably the running.
  • Cycling, with drafting (in elite, draft-legal racing) is not as important.
  • A good runner will be a more successful triathlete than a good cyclist who can run.
• It's important to find a balance.
• Strength training should be included twice a week minimum if you're aiming to improve your performance.
• Other factors that influence running economy are:
  • Gender - men are more efficient than women.
  • Age - we are less efficient as we get older.
  • Ethnicity - we've seen that African runners are more efficient.
  • Anthropometrical factors - if we have a lot of weight in the distal parts of the body (e.g. calf area) this will impair running economy.
• The only factors that we can change are biomechanics and strength training.
• Running technique exercises are key for a basic training plan.
  • These can be included in the warm up at the beginning of the season.
• According to certain new research, we know that a forefoot strike pattern is more appropriate for running economy.
  • But a lot of runners are heel strikers.
    • Barefoot running has been proposed as a strategy to change from heel strikers to forefoot running.
    • Some people are able to do an 8-week barefoot training plan to switch, but it doesn't work for everyone.
• We should aim for long strides and lower stride frequency.
• The first rule of biomechanical change is that every conscious change will negatively affect your running economy.
  • The way you run is the most economical way you can run.
  • The body adapts to that specific form.
• However, we've seen that the best athletes in the world have slightly longer strides and a slightly lower stride frequency.
• If we can unconsciously change our stride length and frequency, for example by getting stronger in the gym, doing strength training or being more flexible, we'll improve performance.
  • The changes have to be progressive and a consequence of training, not a conscious change.

28:50 - 

• When we try to predict performance we have to look for different factors.
• In endurance performance the typical factors are the physiological ones.
  • The three main pillars of endurance performance are:
    • VO2max - this is a good differentiator between bad and good runners, but it can't identify differences between a collection of good runners.
      • A minimum VO2max is necessary to be an elite runner, but after that it wont make much difference.
      • Most of the best African runners in the world have modest VO2max figures of 64-65, which isn't amazing.
      • I myself have a VO2max of 81 and I am definitely not an elite runner that could go to the Olympics!
    • Running economy.
    • Lactate threshold.
• There are other physiological parameters such as brain oxygenation, which looks at how much brain oxygen drops when we are close to exhaustion.
  • We have seen that African runners are able to keep the brain oxygenation stable even at maximal intensities.
  • In Europeans, high intensity exercise leads to brain oxygenation going down.
    • When brain oxygenation goes down by a certain amount we simply stop exercising, so we know it affects performance.
• This happens because when we are exercising at intensities higher than the respiratory compensation point, we are breathing a lot and giving out a lot of CO2.
  • As a result, the partial pressure of CO2 in our blood goes down and this leads to vasoconstriction.
  • The vasoconstriction reduces the blood flow to the brain so the brain oxygenation goes down.
  • This affects the cortical activation of the neurons in the frontal cortex.
  • This area is related to decision making.
• This doesn't happen in African runners.
  • One hypothesis about why this might be is due to early life factors such as exposure to high altitude and high amounts of exercise activities during childhood.
  • As a result of this, they develop certain characteristics including greater vascularisation of the brain.
  • This may explain why they don't suffer from brain oxygenation decrements at maximal intensities.
• Going back to predictors of performance, in swimming and some other sports the biomechanics is a key factor.
  • With a bad technique you cannot be an elite swimmer.
• Similarly in cycling, a good aerodynamic position is important but not determinant.
  • To be a great cyclist you need certain physiological characteristics.
• One of the main determinants of performance, especially at the elite level, is to have a very strong mind.
  • According to Samuele Marcora's theory, the main determinant of performance is the perception of effort. The mind plays a big role.

33:14 - 

• We've seen that the lactate threshold is related to certain heart rate parameters like heart rate variability.
• We are trying to develop a heart rate monitor that can estimate your lactate threshold just by measuring your heart rate variability.
• We are doing artificial intelligence models with an engineering company at the moment.
  • Hopefully in less than 1 year we will have a new heart rate monitor that can estimate lactate threshold without taking blood samples.
• In the future this will be a great thing!

34:10 - 

• What is your favourite book, blog or resource related to endurance sports?
  • Mind, body and the curiously elastic limits of human performance by Alex Hutchinson is a great book. I highly recommend everybody interested in the sport to read it.
  • Related listening: Mind, body, and the curiously elastic limits of human performance with Alex Hutchinson | EP#101
• What's a personal habit that has helped you achieve success?
  • Discipline. You have to be like a soldier. If you have discipline you can achieve everything you want.
• Who is somebody in your field of expertise that you look up to?
  • My former supervisor Timothy David Noakes.
  • Related listening: Psychology and the Central Governor Model with professor Tim Noakes | EP#43
  • Low-carb high-fat (LCHF) for endurance sports with professor Tim Noakes | EP#44

Links and resources mentioned

• The Effect of Periodisation and Training Intensity Distribution on Middle- and Long-Distance Running Performance: A Systematic Review
• Standardization of the Dmax Method for Calculating the Second Lactate Threshold
• Strength and conditioning for triathletes with Frank Velasquez | EP#15
• Brain training and psychobiology of endurance performance with professor Samuele Marcora | EP#17
• Psychology and the Central Governor Model with professor Tim Noakes | EP#43
• Low-carb high-fat (LCHF) for endurance sports with professor Tim Noakes | EP#44
• ​Threshold Confusion: Aerobic, Anaerobic, Lactate, Functional - Help! | EP#71​​​
  
• To lab test or not to lab test with Alan Couzens | EP#79
• The Triathlete's Strength Training Formula | EP#81
• What Type of Run Training Improves VO2max, the Aerobic Threshold, and Running economy? | EP#91
• Mind, body, and the curiously elastic limits of human performance with Alex Hutchinson | EP#101
​

Connect with Jordan Santos

• On Twitter @JordanSudafrica
• On Instagram @JordanSudafrica
• If anyone wants to email about Jordan's research or to request papers: jordan.santos@ehu.eus

Connect with host Mikael Eriksson

Hi! I'm your host Mikael,

I am a full-time triathlon coach and an ambitious age-group triathlete. My goal is podium at the Finnish national championships within the next few years.

I first started the website Scientific Triathlon in autumn 2015 as a passion project to share my learnings with a larger triathlon audience. Later on, in early 2017 I started the podcast That Triathlon Show. 

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