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Every training day is a choice. Hills, or flats? Speed, or strength? A playlist focused on Olivia Rodgrigo’s break-up, or Taylor Swift’s break-up? What keeps me up at night is thinking about how those choices influence long-term adaptation trajectories.
As a coach, an athlete trusts you. You ask some questions and look at some data to get an athlete to reveal the initial conditions mystery: Where are they now, and where did they come from to get here? Those questions are immensely complicated, but you can usually approximate some answers. The questions that come next are why I stare at the ceiling at 2 AM.
Where might their potential allow them to go, and how can they get there?
The first part of that question digs into the interaction of genetics, environment, and behavior. It’s like seeing a little odd-looking rock sticking out on a riverbank in Montana, and realizing that it’s a fossil clue to a T.Rex under layers of sediment. You can never be sure what lies under the sediment, but with experience, you learn that there’s only one approach to finding out: believe, and start digging.
The second part gets into the cellular- and systems-level processes involved in adaptation. Stress plus rest equals growth is a comforting equation to start with. But then you see journeys unfold and start to realize that the wrong types of stress cause regression and the right types of stress lead to breakthroughs. You read the science and realize that no one knows for sure what is the wrong type and what is the right type, and there will never be a universal answer anyway due to unique genetic predispositions and environmental exposures.
RELATED: Tempo Runs 101
So yes, there may be a T. Rex beneath the surface. Here’s a blindfold and some tweezers, let me know what you find in 3 to 10 years.
The choices we make as athletes and coaches determine how that long-term trajectory unfolds. It’s daunting because each choice could be digging in a slightly different direction. Some directions might be wrong and entirely counterproductive, like a faster-twitch athlete doing massive training volume, or an athlete with unlimited speed potential slowing down from excessive vert in training. In a week or month, those choices might not add up to much variation. But over three to 10 years? Crappy choices could leave an athlete thinking they are nothing but barren rock, all while that T.Rex sits untouched forever.
Over time as coaches, my wife Megan and I (our podcast here!) have gathered lots of data that make the line from intervention to outcome a bit less blurry. The big two principles are what you’d expect from training theory: develop the aerobic system with plenty of easy running and/or cross-training, while building top-end output via strides and fast running. Those general elements are as close-to-universal as you’re going to get (and even they have exceptions). But what about workouts?
Each workout is a choice, a Choose Your Own Adventure novel that can have unpredictable outcomes. And it’s all compounded by the complexity of adaptation, which involves too many interlocking physiological variables to ever predict with certainty.
That’s why we love combination workouts.
As outlined in this 2020 article, combo workouts involve pace and/or time variation across multiple sets that introduce different stresses into a single day. Combo workouts can target a broad range of adaptation stresses given the variation in output, duration, and recovery. In our team data of pros racing on the trails and road/track to beginners just starting workouts, combos seem to have the most correlation with long-term progress in races (subject to a million confounding variables, like perhaps the athletes doing more complex workouts are more motivated, or maybe we are more willing to write extra lines in the training logs of athletes that are receptive to doing lots of mid-run math).
The 2020 article gets into the physiological reasoning. Going a bit further, what is most intriguing to me is how the multiple types of adaptation stresses interact to spur adaptation. I think the contrast with cycling is helpful, since the bike turns athletes into power generators plugged into the aerobic system, whereas running has unique biomechanical and neuromuscular demands that make fatigue act slightly differently. Example time, mothertruckers!
Workout 1: 2 x 20 minute tempo with 5 minute easy recovery
If you have read about cycling training, you’ll know this as the workout of death. Do it (or variations of it involving tempo intervals with recovery) over and over and over until you quit the sport and take up something less painful, like having bamboo shoots stuck under your fingernails. It’s notorious because it maximizes the amount of upper-level aerobic power that most athletes can put out in a single session. Consider the sponge totally wrung out.
Would that workout be smart in running? Perhaps, for a highly advanced athlete, in moderation during heavy training builds. But most runners will likely fatigue to the point that they have to reduce output on the second tempo, or start so slow that they end up getting a bit better at being a bit worse than they could be. The sponge gets slimy and raggedy before it gets wrung out. All of that brings us to the crux of the article, and two workouts I think would be better for most runners.
Workout 2: 20 minute tempo, 5 minutes easy, 6 x 2 minute hill or flat intervals with 2 minute easy recovery
Workout 3: 10 x 1 minute fast with 1 minute easy recovery, 5 minutes easy, 20 minute tempo
In Workout 2, athletes can really nail a fast and efficient threshold-or-harder effort (see tempo discussion here). Many athletes could follow that up by nailing the hills, calling on higher levels of muscular power to finish the workout fully fatigued, sponge wrung out entirely, while still going fast enough for optimal neuromuscular adaptations.
In Workout 3, the fast minutes to start will be smooth and strong, followed by a tempo that may have some fade at the end, but is a wonderful aerobic stimulus on top of that neuromuscular stimulus on the intervals.
And for both workouts, they target a wide range of physiological systems. For athletes that may be at their limits and searching for every marginal gain (like pros), combos can lead to unique compounding gains. Some speed after tempo or some tempo after speed just hits differently, and we can have theories for why (protein expression? mitochondria? EPIGENETICS?!), but all we truly know is that it works. That’s why different types of combo workouts are a staple of most track training, where every tenth of a second counts.
For everyone else, combos can be more fun and quite effective. If we can’t be exactly sure what sh*t will stick against the wall of long-term adaptation, sometimes the right answer is to confidently and consistently throw all different types of sh*t.
Tempo run combos approach one of those difficult training choices. Speed, or strength? And they answer… Why not both?
There are two ways to do tempo run combos.
Each of these approaches can be incorporated into your training once a week after you have a base of aerobic running and speed from strides, ideally in the middle of training builds. We like 5 minutes between the workout portions to allow for lactate clearance and provide a mental reset. Advanced athletes may even do cruise intervals or marathon-paced work to replace the tempo, but this article is long enough already.
Option 1: Tempo before intervals
Over time, this workout style has become one of my favorites for advanced athletes training for longer races, and it has been a building block for athletes we coach. The tempo is a quality threshold stimulus, around 1-hour effort or a bit easier to start, with some progression of effort in the second half. The intervals are usually on hills if we’re working more on power/climbing (or for master’s athletes), or flats if an athlete is developing their speed.
Note: Doing the higher-output work on slightly fatigued legs could be detrimental to athletes doing very short races that require max output, like track racing
For the tempo, 15-30 minutes is a sweet spot. For the intervals, 8 to 16 minutes of harder efforts really pushes the body to the within-day limits. Make sure the intervals involve nearly equal rest to avoid the pitfalls of output falling off a cliff with fatigue. Examples:
20-30 minutes at 1-hour effort with light progression in the second half, 5 minutes easy, 4-6 x 2 minute hills moderately hard with run down recovery
15-20 minutes starting at 1-hour effort and ending harder, 5 minutes easy, 1/2/3/2/1 minutes fast with 1-2 minutes easy recovery
30-60 minutes starting at marathon effort and ending around 1-hour effort, 5 minutes easy, 8 x 1 minute hills moderately hard with run down recovery
Option 2: Tempo after intervals
Coach Megan is partial to this approach and seeing the results of her athletes over time, I have become a convert too. The intervals are often high output, 10k effort or harder, like any other workout. The tempo is less about controlling effort and more about doing what you can with what you have. Most athletes will feel aerobically tapped out by the end. But then a cool thing often happens. The next time they do the same type of workout, the tempo is faster at the same or less effort. Adaptation station!
For the intervals, 10 to 20 minutes of harder work is ideal, in 1-3 minute intervals with half to equal recovery. Think of it as a workout that could stand on its own, you’re just adding a cherry on top… the tempo. A tempo of 10 to 20 minutes is plenty, starting at the low end unless you’re used to these types of difficult sessions. Examples:
10-15 x 1 minute fast with 1 minute easy recovery, 5 minutes easy, 15-20 minutes at 1-hour effort
5 x 2-3 minute hills mod/hard with run down recovery, 5 minutes easy, 10-15 min at 10k effort
4-8 x 3 minutes fast with 1-2 minutes easy recovery, 5 minutes easy, 20-30 minutes starting at marathon effort and ending harder
If these tempo combos were the only type of workout I could ever give to athletes, I think I’d be able to sleep at night. For a short distance runner, some tempo after fast intervals supports long-term aerobic growth. For a long-distance runner, tempo before or after hill intervals will harden them to the unique demands of fatigue resistance, while helping them get faster.
Tempo run combos don’t solve the adaptation mystery, because nothing ever will. But they may help us get closer to an answer that works for our unique potential.
Because every single one of us has so much to discover beneath the surface. Whether that digging leads to a full T.Rex or one of those badass little monsters that killed Newman in Jurassic Park…. well, we’ll need belief and 3 to 10 years to find out.
David Roche partners with runners of all abilities through his coaching service, Some Work, All Play. With Megan Roche, M.D., he hosts the Some Work, All Play podcast on running (and other things), and they wrote a book called The Happy Runner.