The Need for Speed - Volume 2

Coach Max Frankel's series on why triathletes NEED to train at higher intensities

Max Frankel is a former elite cyclist and collegiate runner and is currently a triathlete and coach based in Boulder, Colorado. Max is an accomplished coach in the marathon, track, and both short and long-course triathlon having coached multiple athletes to professional licenses in triathlon, wins at the marathon and ultramarathon distances, and numerous Boston Marathon, Ironman World Championship and 70.3 World Championship qualifiers. 

  • If you’d like to inquire about his coaching, or have any questions/feedback on this new segment of The Tempo, feel free to drop Max an email at [email protected]

Welcome back to The Need for Speed! In Volume 1, we introduced an overview of why polarized and high-intensity training matter for triathletes, even and especially including Iron distance-focused athletes. In this week’s edition, I’d like to discuss some practical applications of that philosophy, and how that plays out in designing training programs.

Sustainable fitness and strength in any zone come from cultivating holistic strength and proficiency in the zones both above and below the one you’re looking to improve. Before we get any further, I want to clarify what I mean when I discuss zones. I also want to emphasize that I am applying these principles to running and cycling only, for now. Many of these lessons do have a place in swimming, but proper swim training tends to rely less on zones of intensity than feel, perceived effort, and technique (all three of which are inextricably linked). 

Many runners and triathletes are used to a 5 zone model that looks like this:

  • Zone 1: Active Recovery (0-55% of threshold power)

  • Zone 2: Endurance (56-75%)

  • Zone 3: Tempo (76-90%)

  • Zone 4: Threshold (91-105%)

  • Zone 5: VO2 Max (106-120%)

However, a lot of what we’re discussing in The Need for Speed series covers an intensity not represented by that breakdown - above 120% threshold, or zone 6: neuromuscular power. 

For many triathletes, zone 5 is considered high-intensity speed work. Running sessions might look like 400m repeats at 5Km pace, which is ~ 110% threshold, and not even touching on the upper end of zone 5. At 115 to 120% of threshold we’re still talking about intensities that represent an all-out effort no shorter than 5 minutes.

  • If you told a swimmer that their speed work would all take place at 500y/400m race pace or slower, they’d casually and effortlessly laugh you off the pool deck at such a suggestion. 

Many triathletes seem to have a psychological attachment to training primarily in zone 3 because;

  • It’s hard (but not excruciating).

  • Doing it feels good and results in big endorphin releases.

Triathletes also apply the mantra “you are what you train” as a justification to stick to training in zone 3, because it represents their race intensity.

However, while it is true to some extent that “you are what you train,” the correct interpretation of that looks a little different. Each zone plays a role in increasing your capacity in the others, and getting more sustainably fit at one output relies on adaptations you’ve made above and below it. In other words;

Being well-rounded comes from a well-rounded approach to training, and that well-roundedness in turn can develop higher capacities at specific intensities within the spectrum. 

If you’ve made it this far, you’re probably a real-life nerd like me or have some desire to become one, so I’ll be a little less careful to not throw out dense physiological explanations that may otherwise lead readers to ask themselves how they possibly got down this rabbit hole. 

  • “You are what you train” is a mantra many of us have heard but its best application is an understanding that without training all intensities across the board, you become overly specialized - even if that is a goal within a racing context, that is not a good thing physiologically. 

Let’s start with zone 3, the one that, at the risk of sounding overly blunt, here is the most important for long-course triathlon racing and arguably the least important for training. Before I get hate mail, give me a chance to rephrase:

👉 Training zone 3 is incredibly important, but unless you are training holistically, with plenty of high and low-intensity sessions to complement your race pace work you’re leaving watts and speed at that pace on the table - possibly quite a lot!

  • Zone 3, as the name suggests, lies between zones 2 and 4, but is also the product of metabolic efficiency at its bordering zones as well. 

Zone 2 is purely aerobic, with a minimal reliance on carbs to provide fueling. Heart rate and power remain “coupled” together with little to no cardiac drift and almost all power is provided by contractions of slow twitch type 1 muscle fibers. Lactate is being accumulated just as efficiently as it’s being shuttled back out of the bloodstream. 

Zone 4 on the other hand, occurs at or near the maximum aerobic intensity we can hold with some degree of sustainability. Zone 5 represents maximal aerobic power, or MAP - which we’ll get into later - but that level of intensity is far less sustainable than zone 4.

  • Power at zone 4 is the product of our baseline low intensity aerobic capacity built in zone 2 and the oxygen consumption ability we have in our zone 5. 

If how good we are in zone 3 is determined by how good we are in zones 2 and 4, and how good we are in zone 4 is determined by zones 2 and 5, you might notice a pattern forming at this point: sustainable fitness at any intensity is determined by the sustainability of fitness at intensities above and below it, and this relationship is cyclical. Zone 3 is fed by zones 2 and 4; zone 4 is fed by zones 2 and 5… but competency in zone 3 doesn’t feed back to anything other than itself. 

Thus we’ve arrived at one of our first major principles: training in zone 3 is important to get better at race pace, but it is only one small part of getting better. Without a focus on higher and lower intensities as well, hammering zone 3 all the time will lead to stagnation and a very shallow depth of fitness.

  • The next edition will explore more of how the zones play off of each other and why intentional training across a variety of intensities is typically the best method to ensure continued success. 

  • In a future installment of The Need for Speed, I’ll discuss what Zone 6 training looks like, and why training it is critically important.

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