Podcast, Science, Training

Bas van Hooren | EP#411

 October 9, 2023

By  Bernardo Gonçalves


Bas van Hooren - That Triathlon Show

Bas van Hooren is a sport scientist, sport science consultant, and a runner with multiple national championship medals. In this interview we discuss a number of topics Bas has researched, including practical applications of these findings.

In this episode you'll learn about:

  • Are cool-downs necessary?
  • Is there a physiological or biomechanical difference between treadmill and outdoor running?
  • What do we know about the physiology and training characteristics of the best older athletes in the world (70+)?
  • Are there "sensitive periods" and what are the issues with the Long-Term Athlete Development model?
  • Strength and conditioning science and application for runners and endurance athletes
  • Devices and technology

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Bas' background

02:35 -

  • I primarily work at the University of Maastricht in the Nutrition and Movement Sciences Department. 
  • My research there covers various topics, most related to running. Additionally, I'm involved in a governmental organisation called Top Sports Topics, where I provide evidence-based answers to questions from national-level coaches about training, nutrition, supplements, and more.
  • I also work with an ARION wearable tech company in Eindhoven, Netherlands. ARION specialises in pressure-sensitive insoles that measure various metrics during running and other movements.
  • As for my athletic background, I started running during high school and discovered I had a talent for it. Despite minimal running training, I achieved a third-place finish at the national cross-country school championships. This success motivated me to pursue running more seriously. 
  • Over time, I increased my training volume and adjusted the intensity, gradually improving my performance. 
  • I still enjoy competing and aim to achieve personal bests, win national titles, and potentially participate in European Championships.

Cool down

05:32 -

  • This is a comprehensive review I conducted, stemming from my own practical experience as an athlete and a background in coaching. 
  • I became curious about the effectiveness of cool-down routines because they are commonly recommended for better recovery and performance. 
  • However, I wanted to investigate this from a scientific perspective.
  • During the review process, I encountered the challenge of defining and measuring recovery. 
  • Recovery can be subjective, involving factors like how individuals feel after a cool-down, or somewhat subjective, such as assessing muscle soreness. 
  • On the other hand, it can be objective, including measures like muscle damage from biopsies, lactate levels in blood or muscle tissue, and hormone concentrations.
  • Surprisingly, our review found limited pronounced benefits across these objective metrics when comparing cool-downs to not doing any after exercise. 
  • We also considered overall performance, which encompasses these various objective measures. Our analysis yielded similar results.
  • We examined performance in two ways: same-day performance and next-day performance. 
  • For elite athletes who engage in multiple sessions or competitions on the same day, we found that cool-downs were unlikely to have any beneficial effects, and there might even be negative impacts.
  • For next-day performance, it was mostly inconclusive, although there were indications that, for some individuals, cool-downs might have a slight positive effect. 
  • However, for the majority, they were unlikely to make a significant difference.
  • Additionally, we looked at adaptive responses. Some recovery modalities, like cold water immersion and vitamin supplementation, can suppress the body's adaptive signalling pathways. We explored whether cool-downs had a similar effect. Surprisingly, we observed a trend in the opposite direction. 
  • Regular cool-downs seemed to lead to slight performance improvements. This suggests that cool-downs might not necessarily enhance recovery but could provide extra training volume, indirectly benefiting performance.
  • From a practical perspective, I've always viewed cool down as a way to accumulate more training volume rather than as a method to enhance recovery. 
  • For example, if I plan to work on the track, I can run to the track, do a bit of extra warm-up, complete my workout, and then run back home. 
  • This allows me to achieve a longer overall run time. The cool-down itself doesn't necessarily provide extra value for recovery, but the additional volume is beneficial.
  • Many people face time constraints when it comes to training, so dedicating 15 minutes to an extensive cool down might not be practical. It's often more efficient to use the time for focused training and allocate a brief cool down to reduce immediate post-workout sweating.

Running outdoors vs treadmill

12:41 -

  • Many coaches and athletes recommend using a 1% incline on the treadmill to simulate the physiological demands of outdoor running more accurately. 
  • However, my research yielded some intriguing findings.
  • First, when it comes to physiology, I discovered that among numerous studies (approximately 20), only one supported the idea that setting the treadmill to a 1% incline better matches the physiological demands of outdoor running, particularly regarding oxygen consumption. 
  • The other 19 studies, on the other hand, indicated that running on a treadmill with a 0% incline (no gradient) still provides the same physiological stimulus as outdoor running. 
  • Therefore, based on this extensive review, I recommend that there's no need to set the treadmill at a 1% incline. Keeping it at 0% will suffice to replicate the physiological demands of running on solid ground.
  • You might wonder if an incline's need depends on running speed. Indeed, as you run faster outdoors, you encounter more wind resistance or drag. 
  • However, I also conducted a meta-regression analysis to examine whether the effect changes with increasing speed. 
  • Interestingly, my analysis suggested that up to 16 km/h, setting the treadmill at a 1% incline does not provide any significant advantage over a 0% incline in terms of matching the physiological demands of outdoor running.

Biomechanical differences running outside vs treadmill

15:22 -

  • There are subtle differences between treadmill running and running outdoors. 
  • We conducted a meta-analysis of existing studies and found minor discrepancies in variables like contact time. 
  • For instance, on a treadmill, the contact time was about five milliseconds longer than outdoor running. 
  • However, this difference is so minute that it may not be practically significant, given that a typical contact time for a recreational runner is around 250-280 milliseconds.
  • These variations fall within the typical margin of error in measurement. 
  • In most cases, treadmill running biomechanics closely mirror those of outdoor running. There are exceptions, though, and two key factors contribute to this. 
  • First, individuals may not be accustomed to treadmill running. 
  • For accurate gait analysis on a treadmill, it's advisable to allow at least eight minutes for participants to get accustomed to the machine. 
  • Early measurements may reflect the adaptation process rather than the true running technique.
  • The second factor is the stiffness of the treadmill surface. 
  • A comprehensive study compared treadmill surface stiffness with overground surfaces, including concrete, tracks, and artificial turf. 
  • Most treadmills have a surface stiffness more akin to artificial turf than to concrete. This difference can influence leg stiffness as the body adapts to the surface it's running on.
  • For a treadmill to perfectly replicate the experience of running on concrete, it would require a very rigid surface, often found in specialised clinical-grade treadmills. 
  • In typical gym settings, treadmills have a more compliant surface, which can subtly affect running mechanics.
  • Contrary to a common myth, you don't need to push off less on a treadmill; you still need to generate equal force to stay on the moving belt. 
  • There are some subtle differences in mechanics, but they might not be too relevant for the average listener.
  • Running on a treadmill can be effective, especially at lower speeds. 
  • You don't necessarily need to set the treadmill to a 1% incline to mimic outdoor conditions; running generally on the treadmill can be biomechanically and physiologically similar to outdoor running. 
  • It can be a convenient option when the weather is unfavourable for outdoor training.
  • However, I should note that treadmill running might not help you develop pacing skills as effectively as outdoor running. 
  • On a treadmill, you simply set a pace and maintain it, whereas outdoor running requires more self-regulation.
  • Regarding treadmill running, core body temperature can become challenging, especially in workouts with active recoveries and longer intervals. 
  • The lack of natural airflow and cooling when running outdoors can lead to overheating, mainly if you're doing longer intervals with shorter recovery periods that involve jogging instead of passive rest. 
  • In such cases, I also prefer to take these workouts outdoors when possible.
  • Shorter intervals with passive recoveries tend to be more manageable regarding core body temperature when done on a treadmill. 
  • However, you're right; the effectiveness of treadmill workouts can also depend on the ventilation quality and the gym's temperature.
  • Another factor to consider is the speed adjustment on the treadmill. Some treadmills may take some time to reach higher speeds, which can be less conducive to certain types of interval training. 
  • When you want to quickly reach and maintain a specific speed, especially for shorter, faster intervals, it can be frustrating if the treadmill doesn't respond as quickly as you'd like.

Older athletes

22:09 -

  • Two world-class master athletes were the subjects of the study. At 75 years old, Hans had an exceptional VO2max of 50.5 mL/kg-min, the highest ever recorded for someone his age. 
  • He also exhibited a significant anaerobic speed reserve, which explained his success in the 800 meters, where running at or above VO2max speed is expected.
  • Jo, 71 at the time of measurement, had a VO2max of 46.9, still remarkably high for his age group. 
  • His standout feature was his exceptional running economy, meaning he had a low oxygen cost during running. This efficiency and his high VO2max contributed to his world record-breaking performances in marathon and ultra-marathon running.
  • Comparing Jo's values to a previous world record holder revealed that their VO2max was similar. 
  • Still, Jo's superior running economy could be attributed to his high training volume of approximately 140 kilometres per week, which is exceptional for someone in their 70s.
  • Consistency in training was a key factor for both athletes. Hans had trained consistently for 25 years without missing more than a week of training, while Jo had trained every single day for two years leading up to his marathon world record performance. 
  • This consistency in training played a crucial role in maintaining their performance at their respective ages, as injuries at older ages can rapidly decline performance.
  • It's fascinating to see how both athletes started their running careers relatively late, beginning at 36 and the other during his later years. 
  • This illustrates that it's never too late to pursue a sport, and their journeys from late starters to world-class athletes are truly inspiring.
  • Starting later in life might have its advantages, such as not having prior peak performance times to compare to. 
  • This can help maintain motivation and focus on the present rather than past achievements. 

Sensitive period and long-term athlete development model

30:02 -

    • The concept of sensitive periods in athletic development has been influenced by research on singing birds.
    • In birds, there are critical periods during which they must hear certain songs to learn them; otherwise, they cannot learn them later.
    • This concept has been applied to humans and athletic development.
    • Natural development studies have examined how individuals improve performance skills due to growth and maturation.
    • During childhood and adolescence, there is variation in the timing of performance improvements, such as sprint speed, grip strength, and flexibility.
    • It has been hypothesised that humans also have sensitive periods during which they are exceptionally responsive to specific training stimuli.
    • Training during these sensitive periods, such as agility, speed, endurance, or flexibility training, is believed to lead to significant long-term performance improvements.
    • The concept of sensitive periods has been incorporated into models like the Long-Term Athlete Development (LTAD) model.
    • The LTAD model suggests specific sensitive periods for training physical attributes like speed, strength, flexibility, and endurance.
    • Despite the initial interest in sensitive periods, the author conducted extensive research but found little empirical evidence to support their existence.
    • The complexity of sports performance, which integrates psychological and physical factors, makes it difficult to isolate and measure specific attributes that align with the concept of sensitive periods.
    • Sports performance is multifaceted and involves a combination of psychological and physical factors.
    • Attempts to measure specific attributes like strength, flexibility, and endurance often oversimplify the complexity of real-world sports performance.
    • These models attempt to isolate different components of athletic performance, such as strength, sprinting, and agility and assume that each has distinct neural and developmental pathways.
    • However, the problem with this approach is that there aren't separate neural components solely responsible for strength, speed, or coordination. 
    • While there are variations in coordination within the brain and muscles, they all operate within the same system.
    • The concept of sensitive periods for these different performance components doesn't align with how our bodies work. 
    • In our review, we didn't find any substantial evidence supporting the existence of these proposed sensitive periods in the literature.
    • Interestingly, a study suggests that training speed during the supposed sensitive periods might be less effective than training at a younger or slightly older age. This finding challenges the notion of sensitive periods further.
    • While models may suggest specific periods for training particular abilities, such as speed or coordination, they often lack detailed guidance on effectively implementing these training methods. 
    • Furthermore, it's essential to recognise that many of these abilities are interconnected, and you can't isolate them entirely. 
    • For instance, when doing speed training like sprints or strength training like squats, you're inherently working on coordination to some degree.
    • In practical training, it's more valuable to take a holistic approach and focus on developing a well-rounded set of motor abilities. 
    • While you can emphasise specific areas, there's no need to overly fixate on sensitive training periods. 
    • Instead, consistent and balanced training over time yields the best results, allowing athletes to naturally develop various physical skills.
    • The key is ensuring that training programs are tailored to an individual's goals, abilities, and needs and executed safely and progressively.

Strength training

39:04 -

  • We explored a novel strength training approach, specifically at cluster training or rest redistribution within sets. 
  • Traditionally, strength training involves doing multiple sets with a fixed number of repetitions, such as three sets of five repetitions with three minutes of rest between sets.
  • In cluster training, we introduced additional rest within each set. For example, instead of doing all five repetitions consecutively, we did three repetitions, took a minute of rest, and then completed the last two repetitions. 
  • This approach can be applied to various strength training exercises, including squats, weightlifting, and jumping.
  • Our findings indicated that cluster training had advantages for specific outcomes, particularly those related to explosiveness, like jump performance. 
  • Cluster training showed more benefits than the traditional set structure with continuous repetitions and fixed rest intervals between sets. 
  • The underlying mechanism is that introducing rest between repetitions allows for faster recovery of the neuromuscular system. 
  • Consequently, athletes can generate slightly higher power output and achieve a slightly higher rate of force development during the later repetitions. 
  • Over time, this leads to improved neuromuscular adaptations, which aligns with our previous research findings.
  • I would recommend using heavy weights in your training regimen from an endurance perspective. Cluster training can be particularly beneficial in this context. 
  • In cluster training, you can perform a set of, for instance, five reps. However, you can break this set into smaller clusters, like doing the first three reps, taking a one-minute rest, and then completing the last two reps. 
  • This approach allows you to reduce the overall rest period between sets.
  • Alternatively, if you typically take a more extended rest period (e.g., four minutes) between sets, you can incorporate shorter rests within the set. 
  • For example, you might allocate two minutes for the rest within the set and keep the remaining two minutes as the inter-set rest. 
  • This adjustment can help you manage your training duration more effectively.

Strength training practical applications

43:00 -

  • Regarding my strength training routine, I like to keep it within an hour, which sets a time constraint for the exercises I include. 
  • I aim for about three to four different exercises during this time. 
  • I usually incorporate two heavy resistance training exercises and one or two plyometric exercises, although the mix may vary between sessions.
  • For the heavy resistance training exercises, crucial for tendon adaptations, I focus on using heavy loads, typically above 85% to 90% of my maximum voluntary contraction. 
  • The goal is to achieve sufficient strain for tendon adaptations, crucial for injury prevention and performance improvement, such as enhancing running economy. 
  • My recommendation here is to use a weight that I can lift about six times but stop at the fifth repetition, leaving one repetition in reserve. 
  • This approach avoids training to muscle failure, which can lead to hypertrophy, something endurance athletes typically want to avoid. 
  • However, it still provides the neuromuscular stimulus necessary for strength adaptations. I usually perform three to four sets of these exercises.
  • In addition to heavy resistance exercises, I complement my routine with plyometric exercises like box and drop jumps.
  • Regarding lifting explosively, I use the intent to lift as explosively as possible. Even when lifting heavy weights, the goal is to make the concentric phase as fast as possible, while the eccentric or lowering phase typically takes two to three seconds.
  • As for single-legged versus double-legged exercises, I tend to focus more on single-legged exercises. They offer specificity and can be very effective once you've become proficient in them. 
  • However, there are instances where double-legged exercises can provide a bit more overload, although they might be less specific. 
  • For example, I often prefer single-legged exercises like split-step squats. Still, for exercises like deadlifts, where single-leg variations can be challenging, I opt for double-legged deadlifts. 
  • In terms of strength training exercises, I'd start with single-leg squats. Initially, I wouldn't go too heavy but aim to progressively increase the weight. 
  • This exercise targets the glute quads and can improve neural and voluntary activation in those muscle groups. 
  • It also benefits the patellar tendon, an injury-prone area in endurance athletes. 
  • So, it serves both performance enhancement and injury prevention purposes.
  • Another essential exercise would be heavy-loaded calf raises, focusing on the Achilles tendon. 
  • Research suggests a strong Achilles tendon is crucial for running economy and injury prevention.
  • I'd also incorporate plyometric exercises like drop jumps or box jumps, emphasising maximum effort. These exercises are proven to enhance performance.
  • Depending on the season phase, I might include heavy deadlifts or step-ups.

Devices & Technology

48:47 -

  • When it comes to recommending wearables for runners, I find it a tricky question because the accuracy of many devices can be questionable, even for equipment where accuracy would be expected. 
  • This uncertainty makes me somewhat hesitant to endorse a wide range of wearables.
  • Furthermore, even when we have reasonably accurate wearables, there's often a lack of clear guidance on interpreting the data they provide. 
  • For instance, in biomechanical research, we often don't have well-defined thresholds for what constitutes "good" or "bad" data. 
  • So, while we can measure things with great accuracy, we may still struggle to understand the significance of those measurements.
  • That being said, a heart rate monitor can be helpful for recreational runners. 
  • It helps individuals calibrate their effort level, mainly if they are unsure what "easy" or "hard" running feels like. 
  • It provides a tangible measure that aligns with their perceived effort, helping them understand whether they are running within their intended intensity range.
  • Additionally, a watch that tracks distance, speed, and pace helps maintain training progress and adhere to a training schedule.
  • Ideally, it would be beneficial to have a wearable that provides personalised feedback on how hard one is running concerning physiological thresholds, like ventilatory thresholds. 
  • Understanding whether you're running below the first ventilatory threshold, above the second one, or below the second one can be valuable information, as these thresholds can significantly impact fatigue levels.
  • I've also explored the potential utility of trend of fluctuation analysis alpha one in assessing fatigue and performance, which could be attractive for runners.
  • In the future, it would be valuable to have wearables that provide metabolic data and offer insights into mechanical loading on various injury-prone tissues. 
  • For example, knowing when you've accumulated enough load or damage on your Achilles tendon to increase the risk of injury could prompt a well-timed rest day or an easier run. 
  • A lot of people expect me to use fancy equipment and do extensive testing, but I don't do that. 
  • One primary reason is that I'm swamped and lack time for extensive testing. Another reason is that I've found that many wearables and testing tools don't provide additional benefits for me.
  • For example, I've used heart rate monitors in the past, and while I still occasionally use them during runs, I've realised that they often tell me what I already know. 
  • I can tell when my heart rate is high during intervals or lower after them without needing a monitor. 
  • Sometimes, my heart rate might be slightly higher or lower when I feel less fit, but this doesn't always correlate consistently. 
  • Initially, these tools helped me become more aware of my feelings and calibrate my perceptions, but eventually, they didn't add much value.
  • I've also tried technologies like detrended fluctuation analysis, which didn't work consistently during running and had technical challenges during cycling. 
  • Many of these technologies are attractive for a few sessions but don't provide ongoing extra value.
  • Part of this is because I've been training for years and know my body well. 
  • For recreational athletes or those who haven't been training at a high level for as long, these wearables might be more valuable over a more extended period.
  • If I were coaching or training someone else, I could see the value in wearables because they provide objective data that can inform decisions. 
  • However, I don't need additional tools to tell me this because I'm training myself and understand how I feel well.
  • I'd like tools that provide specific information about my thresholds and mechanical loading in the future. Still, I'm not sure if wearable technology has reached the level of accuracy I'd want for those purposes yet.
  • Combining accurate wearables to monitor various performance metrics over an extended period could provide valuable insights into what works well for performance and what doesn't. 
  • However, this approach requires a significant investment of time and effort. 
  • I haven't been using wearables lately because I find it challenging to consistently measure and analyse all these metrics, let alone find the time to review and reflect on the data to identify areas for improvement. 
  • While wearables can be a powerful tool for performance optimisation, they require dedication and a structured approach to maximise their potential benefits.

DFA Alpha 1

57:51 -

  • It appears that the technology for measuring specific parameters has its challenges.
  • Even missing just one heartbeat can significantly impact the accuracy of the data. Additionally, there are issues related to setting appropriate thresholds, and now there's a recognition that overall fatigue can affect the values obtained.
  • This means that using DFA-alpha 1 to determine training intensity may only be effective when an athlete is entirely fresh. 
  • When fatigue sets in, it can distort the values and make interpretation challenging. 
  • So, it becomes difficult to determine whether to train below the first threshold, below the second one, or somewhere else, given that fatigue can also influence these values.

Rapid-Fire Questions

58:49 -

What's your favourite book or resource related to endurance sports?

Running: Biomechanics and Exercise Physiology in Practice - book by Frans Bosch. I read it extensively about ten years ago during my training camps. I brought it along five times and would immerse myself in it between training sessions. It's an incredibly fascinating book that delves deep into the fundamental biomechanics of running. 

What's an important habit you've benefited from athletically, professionally or personally?

Planning my training sessions as the first thing in my day. I structure my day around my training because it gives me a sense of structure and discipline. Interestingly, I've noticed that my focus tends to wane when I'm not training, which is rare except during tapering weeks. I've realised I need that training stimulus for physical fitness and mental sharpness.


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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