Podcast, Science and Physiology

Michele Zanini (part 1) | EP#393

 June 5, 2023

By  Bernardo Gonçalves


Michele Zanini - That Triathlon Show

Michele Zanini is a PhD candidate at the University of Loughborough studying the connection between running economy, durability, and strength training). He is also a physiologist and strength and conditioning coach with the Italian Triathlon Federation, and he has been working alongside the legendary running coach Renato Canova. This is part one of a two-part interview.        

In this episode you'll learn about:

  • Michele's role within the Italian triathlon federation
  • How physiologists support athletes and coaches in a high-performance environment
  • Testing protocols and how to make test results actionable
  • Running economy, its determinants, and how it can be improved
  • Durability, its determinants, and how it can be improved

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Michele's background

03:10 -

  • I am pursuing a PhD in exercise physiology at Loughborough University, focusing on the relationship between running economy, durability, and fatigue resistance. 
  • My work involves collaborating with professional athletes in running and triathlon, where I serve as a strength and conditioning coach and physiologist. 
  • I have worked with renowned coaches and experts in the field, including Renato Canova and Rich Blake.
  • My background primarily lies in working with runners, and I have spent several years gaining experience in this domain. 
  • I have even had the opportunity to visit Kenya and work with different coaches to broaden my knowledge. 
  • Besides supporting professional athletes, I also apply my expertise to recreational and non-professional runners.
  • In my PhD research, I aim to understand how physiological factors change as fatigue sets in and how this impacts performance, particularly in running economy. 
  • Additionally, I explore the role of strength training in preventing fatigue development. 
  • I collaborate with experts such as Rich Blake and Jonathan Folan, who specialise in neuromuscular performance and running economy.

Being a physiologist and strength and conditioning coach in the Italian Triathlon Federation

05:59 -

  • In the realm of applied physiology for supporting athletes, there are three primary objectives we aim to achieve in collaboration with the Federation. 
  • The first is racing analysis, where we analyse the specific demands of a race and work with individual athletes to bridge the gap between their current performance and the race requirements. 
  • The second objective is supporting training prescription through physiological testing, ensuring athletes train appropriately and identifying areas needing additional focus. 
  • Lastly, we strive to assist in training methodology and racing strategy by providing evidence-based support, which coaches can tailor to each athlete's needs.
  • An example of how these objectives are implemented is a recent case with an athlete competing in the World Triathlon Series. 
  • This athlete demonstrated strong swimming and cycling abilities but lacked the necessary pace in the run segment of the races. 
  • Reviewing the training logs showed that training was deficient at the required intensity for the run. 
  • In the World Triathlon Series, achieving a top-10 position requires a run time of around 2min55s to 3min2s, with a flat 3min being a standard benchmark.
  • Without training in proximity to these times, it becomes challenging to achieve the desired performance, especially during the run segment following the bike portion. 
  • Consequently, our focus for this athlete has been on developing consistent training in the specific intensity range around or slightly above the second threshold.
  • By analysing race demands, conducting physiological testing, and providing evidence-based support, we aim to optimise athletes' performance and enable them to excel in their respective disciplines.
  • In assessing this particular athlete, it became apparent that they required additional speed support. 
  • While his speed at VO2max and the first ratio were satisfactory, there was a significant gap between VO2max and the second threshold. 
  • Upon examining their training logs, it was evident that the necessary intensity in training was lacking. 
  • This observation intersects with the three critical areas of focus: physiological tests, race demands, and training log analysis.
  • Physiological tests provided insights into the athlete's deficiencies while understanding the race demands highlighted the required running pace at their competitive level. 
  • The training logs revealed a need for more specific work in that realm. It is crucial to progress towards various intensities, with the target speed as the training advances. 
  • This approach encompasses endurance and speed components, gradually honing in on the desired race pace.
  • Unfortunately, the athlete was not consistently hitting those specific paces as indicated by their training log. 
  • Even when they did achieve them, it was for only a tiny portion of the overall workout, which is insufficient considering the distance they would need to cover in a race, such as the Olympic distance of 10 kilometres.

Analysing race demands

13:36 -

  • The work I'm discussing is not solely my own. It is a collaborative effort involving a team of four individuals, including a dedicated data analyst. 
  • This teamwork adds significant value to our research as we bring different perspectives and ideas to the table, ultimately enhancing the overall quality of our work.
  • Regarding data analysis, we utilise Stryd footpads for monitoring running performance. 
  • These footpads are used with athletes before their races, and we record the data they provide. 
  • The footpads offer valuable biomechanical data and are highly accurate in measuring speed. We have conducted comparisons in the lab against treadmills and outdoor tracks, confirming their precision. 
  • Calibrating the foot pods for the specific shoe is essential, as different shoe types can introduce some errors. However, with proper calibration, the footpads provide reliable and accurate measurements.
  • One notable advantage of using the footpads is the ability to track pacing during races comprehensively. 
  • While race splits provide some information, they often do not capture crucial moments, such as the final kick or the initial burst after the bike segment. 
  • With the footpads, we can observe the complete profile of the race, allowing us to analyse how behaviour and performance change throughout the run portion of the event. 
  • This comprehensive insight enables us to assist coaches in implementing pacing strategies and optimising racing tactics for the run.
  • By comparing training data with race data, we can better understand an athlete's performance and make informed adjustments to improve their overall results.

Performance testing and training prescription

16:30 -

  • Finding a balance between thoroughness and efficiency becomes crucial when testing athletes, particularly triathletes with limited time available due to their extensive training schedules. 
  • Complete protocols with high accuracy may require a significant time investment, often not feasible for athletes who train 25 to 35 hours per week. 
  • Therefore, it becomes necessary to streamline the testing process while still capturing essential data.
  • The testing approach may vary depending on the athlete's training phase and goals. 
  • For example, during the early season, the focus may be on the bike segment, ensuring athletes accumulate the necessary kilometres and train at the appropriate intensity. 
  • Alternatively, after a winter period of general preparation, a comprehensive assessment, including biking and running, might be conducted to establish a baseline ahead of races.
  • Swimming testing presents additional challenges, as measuring multiple variables is more complex than running and cycling. 
  • Efficiency becomes paramount to keep the testing duration within a manageable timeframe of 45 minutes to an hour.
  • For biking, a ramp test is typically employed. In contrast, running involves a step test with lactate measurements, as it provides a more reliable method for assessing thresholds. 
  • Ventilation differences between running and cycling can make interpreting running ramp tests more challenging, making lactate threshold measurements preferable. 
  • These measurements, specifically lactate thresholds 1 and 2, offer valuable insights into an athlete's performance markers and the distance between the two thresholds.
  • The ramp test is preferred over the step test for several reasons, primarily because it is quicker and provides more reliable ventilatory thresholds on the bike than lactate thresholds. 
  • Our team has a dedicated physiologist who primarily focuses on the cycling aspect while I take care of strength and conditioning and running. 
  • It is a collaborative effort where compromises are made to find the best approach.
  • In terms of research, the ramp test has proven to be effective and reliable. 
  • However, when it comes to running, there may be more variability and noise due to the impact and bouncing movement, which can affect the accuracy of measurements. 
  • Additionally, ventilation-wise, there tends to be more variability during the ramp test on the bike compared to running.

Other physiological parameters

20:25 -

  • Our testing protocol aims to capture a comprehensive profile of the athletes' performance determinants, including VO2 max thresholds, exercise economy, and strength-related metrics.
  •  We can gain insights into their overall performance potential and developmental progress over time by assessing these factors.
  • VO2 max, whether powered or speeded, provides a ceiling for the athletes' aerobic capacity. 
  • Based on our database, we have established the expected ranges for these types of athletes, including junior and under-23 athletes.
  • This information allows us to track their longitudinal development and assess their proximity to their VO2 max ceiling.
  • Additionally, we examine the two thresholds that delineate different exercise domains: LT1 and LT2 (or VT1 and VT2). 
  • These thresholds indicate the transition from moderate to heavy exercise intensity and heavy to severe. 
  • By analysing their proximity to these thresholds, we can determine the scope for improvement. For example, if an athlete's LT1 is already at 95% of their VO2 max, it becomes challenging to increase it further without raising their VO2 max capacity.
  • Our testing also focuses on assessing fat max for cycling, although we have also considered its applicability to running.
  • However, given the relatively low speeds involved in running, we are uncertain if it would be a trainable metric. 
  • We are not estimating the Fatmax for running but may explore it in the future.
  • Furthermore, we incorporate maximal efforts on the bike to evaluate power production and maximal power output. 
  • These assessments provide insights into the athletes' anaerobic capabilities and overall strength.
  • Lastly, from a strength perspective, we conduct tests such as drop jumps and utilise metrics like mid-type pool. 
  • These assessments allow us to evaluate aspects of strength and reactivity. We typically implement these tests during training camps when athletes gather, enabling efficient and consecutive testing of individuals.

Working with coaches

23:11 -

  • Establishing trust and effective communication is crucial when entering a new coaching environment. It is essential to understand the coach's and athletes' way of working and their preferred methods of communication. 
  • Communicating is vital as it determines the impact and opportunities one can create. 
  • Before providing input, building trust and ensuring that the coach is open to receiving suggestions is crucial.
  • It can be challenging to prove oneself in a new environment where nobody knows your capabilities. Instead of trying to showcase all skills and expertise from the start, it is more effective to provide value gradually. 
  • Taking the time to observe and analyse the coach's work and the team's current approach allows for meaningful insights and suggestions to be offered. It is about understanding what can be improved or optimised based on their existing practices.
  • This approach can be seen in the context of strength training. 
  • A collaborative relationship can be established by observing the athletes' training sessions, engaging with coaches, and gradually sharing opinions and suggestions. 
  • Over time, coaches may begin to seek your expertise and implement your recommendations. 
  • This organic process of understanding the environment, providing insights, and building collaboration can lead to supporting a significant portion of the national team and overseeing the methodology of other coaches.
  • Efficient and effective communication and teamwork are crucial aspects of the collaboration between the sports science team and coaches. 
  • Maintaining a two-way communication channel facilitates the exchange of information, ideas, and feedback. 
  • It is essential to recognise that coaches often face more pressure than the sports science team, as the outcomes of the athletes' performance primarily rely on their coaching strategies. 
  • This understanding can help when introducing new concepts or suggestions, as coaches may require time or specific circumstances to consider implementing changes.
  • Timing plays a significant role in proposing new ideas to coaches. Well-timed suggestions, presented at appropriate moments, can increase the likelihood of acceptance and implementation. 
  • Coaches are generally more receptive to trying new approaches during an offseason or when positive results are achieved.
  • Strategically aligning the introduction of innovative methods with these periods can have a more significant impact and foster a more receptive environment for change.

Running economy

28:13 -

  • Running economy is a crucial factor in determining endurance performance. 
  • It represents the cost of exercise and can be measured through energy or oxygen costs. 
  • Both measures have their merits and can be used depending on the focus of the study. 
  • Running economy becomes increasingly important as the race lengthens because it affects how efficiently an athlete utilises energy during prolonged efforts. 
  • While it may have less impact in shorter distances, like 800 and 1500 meters, it becomes more influential in longer races where aerobic endurance plays a more significant role.
  • Running economy is especially significant for elite athletes, as studies have shown that it can be more strongly correlated with performance than Vo2max. 
  • While Vo2max levels tend to be similar among top athletes, running economy varies, and those with better economies can achieve superior results. 
  • Improving the running economy is a trainable aspect of performance and can substantially impact an athlete's speed at Vo2max and maximal speeds.
  • Longitudinal data on elite runners, such as Paula Radcliffe, have demonstrated that the running economy can be enhanced with training over time. 
  • While Vo2max performance may remain relatively stable, improvements in running economy of around 15% have been observed, leading to increased performance and faster speeds at Vo2max.

Factors that influence the running economy

33:23 -

  • Several factors influence the economy and efficiency of exercise performance, particularly in activities like running. 
  • These factors can be categorised into different aspects, such as physiological, biomechanical, and neuromuscular parameters.
  • Physiologically, factors like fibre type composition play a role. Type I fibres, which are more economical and efficient due to their higher mitochondrial density and efficiency, contribute to improved performance. 
  • Substrate availability and utilisation also affect the economy, as the proportion of carbohydrates and fats used for energy impacts oxygen consumption. 
  • Oxygen availability and delivery, including adaptations at altitude and the enhancement of VO2 max, are additional factors influencing the economy.
  • From a biomechanical and neuromuscular perspective, the stiffness of elastic structures in the leg, particularly the Achilles tendon, plays a crucial role in energy storage and propulsion during running.
  • The ability to efficiently use the energy generated from the landing of each step can significantly impact the running economy. 
  • However, accurately quantifying the contribution of this energy is challenging, and estimations vary in the literature.
  • Muscle activation is another critical aspect affecting the economy, although it can be difficult to measure precisely. 
  • Strength training has been shown to reduce unnecessary muscle contractions and improve muscle efficiency, thereby reducing the cost of exercise. 
  • Other biomechanical parameters, such as ground contact time and vertical oscillations, influence the economy. 
  • A shorter ground contact time and lower vertical oscillations indicate a more spring-like and efficient running style.
  • Lastly, footwear has become a game-changer in running and triathlon.
  •  Properly designed and fitted footwear can enhance running economy by providing cushioning, support, and energy return properties.

Training interventions to improve running economy

40:40 -

  • Several interventions have been explored to improve the running economy. High-intensity training has been found to enhance running economy acutely. 
  • Altitude training can also be beneficial by increasing the mass of red blood cells involved in oxygen delivery to the muscles. Strength training can modify muscle stiffness, improve muscle coordination, and increase individual muscle fibres' strength. 
  • By increasing the strength of each fibre, fewer fibres may be needed to produce the same effort, resulting in improved efficiency. Furthermore, strength training can enhance capillary oxygen delivery and reduce running costs.
  • In terms of specific interventions, a study from 2017 investigated the effects of downhill running on the running economy but did not find significant improvements. 
  • However, it is essential to note that research in this area is often limited by small sample sizes, which may impact the ability to detect meaningful effects. 
  • Another study examined the effects of uphill running interventions. Although some positive effects were observed for specific training sessions, the small sample size (less than six people per training type) makes it difficult to draw definitive conclusions.


44:10 -

  • Durability in endurance performance refers to an athlete's ability to consistently maintain their physiological and biomechanical efficiency over time.
  • Durability encompasses the capacity to sustain performance-related parameters throughout an event or training session, even as fatigue sets in.
  • Research has explored durability in cycling, examining how the power-performance relationship changes with fatigue. 
  • It has been observed that elite cyclists can maintain high power outputs even after prolonged exertion, unlike junior or under-23 athletes. 
  • This indicates their ability to sustain performance at a high level throughout a race or after a significant workload.
  • Furthermore, ongoing research focuses on the impact of interval training on variables such as the power duration curve.
  • Understanding how interval training affects these parameters can provide valuable insights into optimising endurance performance.

Physiological parameters influencing Durability

47:00 -

  • The question you raised about the physiological changes that occur during prolonged exercise is of great interest, and there is ongoing research in this area. 
  • While field data is available, the evidence regarding the specific physiological changes is somewhat limited. 
  • Fatigue-related studies have primarily focused on understanding how fatigue affects the development of specific parameters.
  • One important consideration when examining performance and physiological changes is the specificity of the task. 
  • For example, cyclists who maintain a given power output for several hours must sustain that performance level without experiencing cardiac drift or changes in biomechanics. 
  • In triathlons, the demands and performance determinants differ across disciplines, such as the high-intensity efforts during cycling and the even-paced nature of running.
  • To investigate the physiological changes and their impact on performance, it is crucial to design specific fatigue protocols tailored to the discipline under study. Some general observations include drops in critical power and VT1 (ventilatory threshold 1) with increasing fatigue. 
  • A study in 2022 found that VT1 dropped after two and a half hours of cycling around VT1 in highly trained athletes. 
  • Cycling efficiency and running economy also tend to change, leading to increased oxygen cost and a higher fraction of VO2 max utilisation.
  • Additionally, there may be reductions in VO2 max or VO2 peak, which affects the ability to produce high-intensity efforts.
  • Fatigue-related parameters, both from a central and peripheral perspective, including neuromuscular factors, can change during prolonged exercise.
  •  Dehydration is also likely to occur during exercise, and significant dehydration (above 2 to 3%) can impair performance.
  • The increased core temperature during exercise in hot conditions affects metabolism and may impact homeostasis and performance optimisation.
  • Other parameters that can be affected by prolonged exercise include maximum sprinting speed. 
  • Studies from Finland have reported decreases in maximum sprinting speed of around 10 to 15 % after continuous running. Additionally, measures of W' (anaerobic work capacity) and D' (anaerobic energy reserve) may also be reduced due to fatigue.
  • It's important to note that the relationship between these physiological changes and performance highly depends on the specific event and the level of specificity considered. 
  • The literature in this area is continually evolving, and further research is needed to understand better the complex interactions between physiological changes and performance outcomes.

Fatigued testing

54:18 -

  • It is challenging to conduct the desired testing due to logistical difficulties. 
  • However, it would be valuable to explore parameters that may be influenced by fatigue development, particularly after cycling. 
  • Although we have not yet tested these specific parameters, we have been persuading athletes and coaches to participate. The Danish team is undertaking related research, focusing on half Ironman and Ironman distances. 
  • As for other teams, I am unaware of any currently conducting similar testing during trials or world events.
  • One of the main challenges lies in assessing athletes' capacity without disrupting their training. 
  • With elite athletes, significant changes in parameters require pushing them to their limits, often resulting in two to three days of recovery. 
  • Unfortunately, athletes typically do not have the luxury of time to recover. 
  • Moreover, from a support team perspective, there are limitations on the amount of testing that can be carried out within a given day. 
  • Testing a single athlete may require two to three hours, and when considering a larger group of six or seven athletes, it becomes an extensive and time-consuming endeavour. 
  • Additionally, conducting tests in fresh and fatigued states is preferable, adding to the complexity of scheduling and logistical considerations.
  • Standardising testing for triathletes can be feasible since they consistently train in a semi-fatigued state due to their training volumes. 
  • However, it may require compromising certain aspects. For example, testing VO2 max in both fresh and fatigue states would be ideal for maintaining a similar workout or training session a couple of days before the test. 
  • Conducting such tests during the off-season may not yield accurate results as the athlete's physiology would be different without the accumulated training load leading up to races.
  • One approach that could be helpful in analysing training data, particularly for long rides or runs off the bike, and observing changes over time. This could involve examining variations in heart rate or the ratio between heart rate and pace. 
  • The concept of "decoupling" may be applied, which refers to differences in heart rate and pace during fresh and fatigued states. 
  • Decoupling can provide insights into how the athlete's effort level is affected by fatigue, but it does not directly indicate physiological changes.
  • Field testing may offer some insights, albeit limited from a physiological perspective. 
  • Monitoring factors like pace, heart rate, and decoupling can indicate fatigue's impact on performance. 
  • However, more specialised testing would be necessary to understand physiological changes comprehensively.

Interventions to improve durability

1:01:41 -

  • Several studies and interventions have explored different approaches to enhance performance in a fatigued state. One notable area is the investigation of strength training. A group from Norway conducted research in 2011 involving elite cyclists, where they observed a 7% improvement in five-minute time trial performance after 11 weeks of strength training. 
  • They replicated similar patterns with cross-country skiers and female duathletes in subsequent studies published in 2017. T
  • These studies measured parameters like oxygen consumption and found a decrease in the drift of oxygen during exercise with strength training.
  • Furthermore, a recent intervention conducted at Loughborough University focused on runners. They divided 14 well-trained athletes into two groups and implemented a 10-week strength training program. 
  • The study found that the group undergoing strength training exhibited less drift in oxygen consumption toward the end of a 90-minute run and experienced a 40% improvement in time to exhaustion at 95% of maximal oxygen uptake. 
  • Although no improvement in running economy in a fresh state was observed, these results indicated enhanced fatigue resistance and durability.
  • Other interventions and factors that may contribute to performance in a fatigued state include carbohydrate intake and consistent exposure to aerobic exercise over time. 
  • Some research demonstrated that carbohydrate feeding during exercise helped maintain critical power levels compared to a placebo condition. 
  • The ingestion of carbohydrates supports physiological functioning and reduces the reliance on less efficient fat metabolism during prolonged exercise.
  • Additionally, long-term training volume and consistent aerobic exercise exposure appear beneficial. 
  • Athletes with higher training volumes over the years tend to perform well, as evidenced by comparisons between 123 athletes and world-class cyclists. 
  • Younger athletes can succeed in some sports, such as middle-distance running.
  •  However, for disciplines like the marathon, it is uncommon to see high-performing athletes under 25 or 26. 
  • This suggests consistent training and gradually moving towards longer distances may be essential for athletic development and performance.


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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