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One of the trickiest principles in running training is “supercompensation.” All the time, I talk about how little we actually know about adaptation to training stimuli. I’m like the world’s worst Jeopardy contestant. “What is adaptation? SERIOUSLY PLEASE TELL ME WITH A DIAGRAM AND SOURCES.”
While the specifics are immensely complex and individual-specific, the general idea is pretty simple. Introduce a stress, let the body compensate for that stress during a rest period, grow back stronger.
You can picture it like a gentle wave. The fatigue disturbs equilibrium, causing you to go below baseline, initiating a need to recover, followed by a rise just above baseline. Stack up enough of those incremental improvements, and an athlete can transform over time.
Sometimes, though, we don’t need a wave. Perhaps that gentle oscillation has led to a stagnation period, where aerobic development and muscular strength are leading to more of the same for months at a time. Even worse, maybe an athlete finds themselves getting slower, losing some of the ability to push themselves, without the presence of overtraining or underfueling. In those cases, it might be the neuromuscular and endocrine systems that are not responding as hoped.
Or maybe a big event is coming up, and an athlete knows that they won’t make big waves by relying on small waves. If the first time they push over the edge is on race day, the flood of fatigue byproducts and deluge of muscular strain could leave their potential uncovered.
In those cases, an athlete might not need a normal wave. They might need a MOTHERTRUCKING TSUNAMI.
Why Do Hard Workouts?
Supercompensation relies on incredibly difficult break-down stresses that cause an athlete to build back at levels that may exceed what is predicted by a typical adaptation model. Think of it as an exponential growth stimulus, applied via the chemical context in the cells and the stress felt across the aerobic, muscular, and nervous systems.
What causes supercompensation? Call me Q, because I’ve got some THEORIES. The most direct rationale is that by fully fatiguing the muscles in conjunction with flooding the body with fatigue byproducts, the neuromuscular system interacts with normal muscular/aerobic adaptation processes to cause an unexpected fitness jump. In that theory, the nervous system via something like the central governor (itself a theory about the brain’s modulation of exercise performance) plus cellular-level changes via protein expression (or similar) take control of normal adaptation processes to bump up performance, particularly in subsequent extremely hard efforts.
While that theory is a bit sexy, it’s not going to make anyone storm the Capitol. Put on your aluminium hats and steel-toed tighty-whities, because now we’re diving into the deep end.
Most likely, there is some explanation in the complex interplay of the endocrine system and nervous system. The influx of stress hormone cortisol combined with other hormone perturbations interact with how the nervous system controls fatigue to cause that non-linear growth.
Another theory could involve genetic expression, where some dormant epigenetic switches rely on giving them a really powerful whack. I’ve always said that if it works for a PC computer, it works for the building blocks of life on Earth.
Hard workout principles
While the mechanistic theories for supercompensation are uncertain (and the differentiation between supercompensation and normal adaptation is somewhat arbitrary anyway), the principles of extremely hard workouts throughout a training build are rather constant in elite athlete training. Quenton Cassidy’s 60 x 400 meter workout was fictionalized in Once A Runner, but was exaggerating a relatively common principle for track athletes. Just last week, the social media grapevine indicated that HOKA NAZ Elite did 40 x 400. And before the Olympics, there were whispers of athletes in a training camp doing 6 miles at 5K race pace or faster in a single session. The honorary coach of these workouts is always Kelly Clarkson, because what doesn’t kill you makes you stronger.
Stand a little taller.
Doesn’t mean I’m lonely when I’m alone.
But I digress. My favorite example is a Canova block, involving two hard workouts in one day. The Ingebrigtsen brothers are world-renowned for their double threshold days, with AM and PM tempo-focused sessions (see this 2019 article in the International Journal of Sport Science and Coaching), and brother Jakob just won a gold medal.
Supercompensation For Trail Runners
On the trails, these supercompensation concepts can be a bit tougher to quantify. For track and road runners, you can do a workout until you fall off pace, with supercompensation workouts designed to nudge that inflection point back by splitting it up into two sessions, using combo principles to distribute stresses, or doing an extremely high volume of intervals at slightly slower paces. But most trail runners are not specifically trained to optimize their output on a road or track in the same way, so doing a similar workout would likely just be inefficient and risk injury.
That’s where hills come in. On hills, runners can utilize their disproportionate strength (I’m like an ant carrying a potato chip!) to maximize aerobic and muscular stress without too much impact or injury risk. Focusing the biggest, scariest efforts on hills could improve climbing, but that’s just a secondary goal. The main goal is to improve EVERYTHING, all at once, in a single tsunami of training stimulus.
TL;DR: Empty the tank, see what fills it back up.
BUT! Don’t Empty The Tank Too Often
These types of workouts are reserved for very special occasions, for athletes that are stagnating (while healthy and motivated) or already checking most of the training boxes for sustainable growth. At most, athletes coached by Megan and I will see a workout like this a few times in a training block, usually 3 and/or 6-8 weeks before a big event for most athletes, or approximately every month for pro athletes. All of the workouts end with athletes feeling like they are running through a dirty, nasty sludge.
If you want to mess around with these workouts, we have more disclaimers than a commercial where a guy throws a football through a tire swing. Make sure you have a big base of training, and that you’re confident you can handle the training load. Take at least 2 easy days before and 2 easy days after. Do a very easy warm-up of 15-20 minutes before the workouts, then do a cool-down of stuffing all the food in your house into whatever orifices you can. Splitting each of these workouts in half would be adequate for long-term growth, so these efforts are breaking our usual rule of never compromising sustainability for immediacy.
But rules, like metatarsals, are meant to be broken. Let’s do this.
Workouts Focused on vamLT
A variable we use to project race results is vamLT. Initially a cycling term, “vam” stands for “velocità ascensionale media” or “average climbing speed.” We like vamLT because it has overlap with vLT, or velocity at lactate threshold, a common term used for road running. Also, it sounds exotic, like it’ll bring us espresso while wearing a shirt with just one button.
This first set of workouts aims to maximize climbing ability around lactate threshold, approximately what an athlete could hold for one hour. In our team data, that is the most reliable predictor of peak potential in steep trail races and hilly ultras. They can work as final big efforts 2-3 weeks before longer races, or to replace training races every 4-6 weeks.
One: 15-20 minute tempo around 1-hour effort, 5 minutes easy, 5 x 3 minute hills around 5k effort, 5 x 30 second hills fast
The tempo to start is a wonderful threshold stimulus, with the option to do it on flat or rolling terrain to focus on running economy. The 3-minute hills are a crushing muscular strain on top of that aerobic strain, and the short hills to finish will recruit every muscle fiber and strand of self-belief you have left.
Two: 8 x 2 minute steep hills around 5k effort with light progression of effort in second half of each interval, 5 minutes easy, 15 minute tempo starting at 1-hour effort, ending hard
Starting the combo with steep hills will turn your quads and glutes into a yogurt-like mixture. The aerobic tempo stimulus after the full muscular stimulus really prepares athletes for the ends of longer races.
Three: 10/8/6/4/2 minute hills moderately hard around 10k to start, progressing to hard at the end, 6 x 45 second steep hills fast
The notorious Hill Beast is a staple for skyrunning athletes we coach. By the end of the descending ladder, you’re running on al dente stilts, with the bonus power strain of the steep hills fully launching you into soggy noodle territory. Do it on a steep hill for the entire session and you can be ready for even the most brutal terrain.
Four: 20 minute mod/hard hill climb, 5 minutes easy, 6 x 1 minute steep hills around 5k effort, 5 minute all-out hill climb
Of all the workouts in this article, this one is the hardest for many athletes to complete. The tempo and steep hills will have you hands-on-knees, and working directly into the all-out hill climb is a test of will as much as fitness.
Workouts Focused on vamVO2
While the vamLT workouts all had a strong aerobic component mixing sustainable efforts with hard ones, the vamVO2 workouts are all power, all the time. The goal is to have a complete muscular and aerobic capacity workout, where a coach could surprise you with one more interval at the end, and you’d possibly be unable to do it without a sharp fade. There are parallels in training theory for 10k and below track runners, or even in weightlifting or track cycling.
An athlete with a high vamVO2 has a really high longer-term ceiling, because all they need to do is add some lower-level work to become beasts on more sustained efforts. With that in mind, they are often best 6-8 weeks before longer races, as periodic intense stimuli that support longer efforts, or a couple weeks before shorter races.
Five: 3 x 3/2/1 minute hills around 5k effort, with a bit more effort on the 2s and 1s, 6 x 45 second hills fast
Six: 6 x 2 minute hills around 5k effort, 6 x 1 minute hills a bit harder, 6 x 30 second hills fast
Both workouts involve 18 minutes of intense hill intervals, followed by faster strides to finish. Most athletes will get close to their limits with ~20 minutes around VO2 max on hills, since muscular fatigue becomes a major limiter before the aerobic system is fully tapped out. The bonus hill strides often feel like a welcome respite at first, before the muscles fully give up by the end. For pro athletes, I’ll often program a workout like this every few weeks in heavy training.
Seven: 6 x 90 second steep hills 5k effort, progressing effort as you go, 3 x 3 minute hills all-out
This workout is more focused on the neuromuscular system, as the all-out hills to finish will create a world of hurt that may make future workouts and races feel like worlds of manageable discomfort. Steep hills fatigue the muscles and stimulate VO2 max as a marinade, all-out hills light the stove to 1000 degrees and turn an athlete into a well-done steak. Only do this type of workout in periods of stagnation, or a week or two before intense races.
Eight: 10 x 1 minute steep hills starting hard and ending all-out
The final workout is simple, and relatively short. But it emphasizes how much a training stimulus depends on effort rather than workout design. Do 10 hard hills, and if you push yourself enough, you can transcend what you thought was possible in the future. If you like this sort of workout, or 6 x 2 minute hills, or 8 x 90 seconds, you can push yourself to empty the tank every few weeks with relatively low risk, just make sure you’re always developing the aerobic system.
Keep your fitness tank close to full most of the time. Maybe my favorite article I have written is titled “It Is Good To Feel Good In Running And Life,” describing the physiology of maintaining freshness throughout training cycles. Sustainable adaptation happens when an athlete feels good. But sometimes, to upgrade from “good” to “great,” you have to be willing to feel a bit bad. That’s where these workouts come in.