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An unfortunate part of training theory is that it’s difficult to isolate the true causation relationship of any single intervention. You’ve heard the term “correlation not causation,” right? A more accurate formulation sometimes feels like “solid correlation but not causation unless we’re talking about a specific type of athlete with a specific background when Mercury is in retrograde.” It can feel a bit like astrology, where broad applicability requires general statements that lose some specific meaning. Gosh, that was such a Leo thing of me to say (broad-minded and expansive, yet pompous and patronizing).
While almost all statements of broad applicability in training theory have a laundry list of exceptions, there are a few areas where I have seen the strongest correlation with long term growth in athletes I coach. Resting, eating enough, and a focus on easy running are ones I have written about. Here is another: I think many athletes can benefit from what this article will call power hill strides.
Perhaps the biggest confounding variable of all is that the universe is vast and cold and governed by chaos theory, making any attempt at certainty a Quixote-esque lunge at a windmill. I think that wins for my most nihilistic disclaimer yet.
These 15-to-30-second hill intervals with one to two minutes easy running recovery have been one of the only universal elements in training plans for athletes coached by Megan and me. In fact, when Megan started coaching during medical school, I saw that as she gathered more real-world data, she prescribed these efforts far more often than I had previously. She also added the word “power” as a form/effort cue, though I still just call them hill strides or hills. Her athletes had breakthroughs, and I took notice.
The disclaimer is that it’s all empirical (or anecdotal) rather than proven, and different things can work for every athlete. If hill strides don’t fit with your approach, it’s totally cool to bag them like it’s trash day. Perhaps the biggest confounding variable of all is that the universe is vast and cold and governed by chaos theory, making any attempt at certainty a Quixote-esque lunge at a windmill. I think that wins for my most nihilistic disclaimer yet.
Let’s break down some possible benefits, then get into how to add some power to your stride.
Running economy benefit from higher output running
Numerous studies and empirical evidence indicate that speed endurance training improves running economy, reducing the amount of energy it takes to go a given pace. For example, a 2018 study in Physiology Reports had 20 athletes do 10 sessions of 30-second intervals in a 40-day study period while reducing overall training volume, and their 10K times and velocity at VO2 max improved by a couple percent.
It’s all variable, but the intuitive conclusion is probably right: for sustainable, efficient output in most endurance events, you need to be able to put out short-duration, higher output efforts too.
In addition, most training approaches in narrow-margin settings (like road marathons and track racing) have some emphasis on high-output, short strides at some point in training cycles. And fast road and track athletes who can run effectively on trails almost always excel. It’s all variable, but the intuitive conclusion is probably right: for sustainable, efficient output in most endurance events, you need to be able to put out short-duration, higher output efforts too. A car probably can’t hold 80 mph on the interstate if its top speed is 85 mph. Why might short intervals be effective even if they look nothing like the races and adventures we are training for?
Possibly minor aerobic adaptations for heart and oxygen processing
A super-small ingredient may be aerobic adaptations. On strides, your heart rate rises rapidly—I’ll sometimes see athlete graphs where heart rate goes from 120 to 180 seemingly in an instant. That process could have cardiac output benefits. On the flip side, too much high intensity work could lead to aerobic inefficiency, so it needs to be balanced.
Potentially major adaptations for musculoskeletal system
My hypothesis (i.e. throwing a dart against a guess board) is that musculoskeletal adaptations are the key element in hill strides. Each stride provides a stimulus with substantial force in a short time. In addition, unlike flat-ground strides, most athletes will self-select a lower cadence that is more similar to sustainable faster running.
For example, an athlete that races at 180 strides per minute may do a flat-ground stride at 210-220 strides per minute and a hill stride around 180-190. To throw another guess dart, maybe the higher output per stride makes hill strides improve muscle output in a way that is conducive to sustainable improvement (though there is probably a place for strides on both hill and flats, particularly when thinking about neuromuscular adaptations). Plus, doing efforts on hills often comes with reduced impact forces and strain on musculotendinous units, possibly reducing muscle pulls and other injuries.
Plus, doing efforts on hills often comes with reduced impact forces and strain on musculotendinous units, possibly reducing muscle pulls and other injuries.
If that paragraph had any more uncertain guesses, it’d be leading a pandemic task force.
Potentially major neuromuscular adaptations
The role the brain plays in the complex task of running is easy to overlook, but neuromuscular changes can explain large variations in performance over time. In some studies, authors theorize that maximization of motor unit recruitment seems to play a role in improved running economy. To simplify it, you have to learn to maximize output and go fast, and that stimulus needs to be reinforced consistently for many athletes (with variation based on age, background, and goals).
How we use power hills strides
For our athletes, we generally introduce hill strides early in training as a low-impact way for athletes to adapt to higher-output running. This approach seems to be effective from the beginner level to professionals. After they adapt, flatter strides often become a bigger part of training to develop top-end speed, though the approach varies. Once they can actually go fast, hill strides again become a primary focus to work on output over time. Masters athletes and athletes that have had injuries in the past may focus on hill strides all year.
Side note: seeing the success of some of the athletes that had a heavier emphasis on hill strides is what led to them becoming a bigger part of the focus for all of our athletes. “Nancy’s Hills” are an alternate name we use for this style of hill stride, after age-group champion Nancy Thomas, who added 20-second hills to many of her runs.
The final recipe we use: feed the neuromuscular stimulus back into musculoskeletal and aerobic adaptations, layer it on a balanced long-term training plan focusing on health and adaptation, mix it with environment and genetics, and bind it all together with pizza.
Reminder: if we delved into the physiology more deeply, there’d be an immense amount of uncertainty next to almost every term and clause above (except for the pizza thing). The interaction of training theory with biology is so complex that any distillation of it is lacking by definition. You know what’s not lacking? Pizza. Pizza: because the universe may be cold and uncaring, but your warm slice loves you.
For our athletes, we have developed a general approach to hill strides. Now we’re venturing to anecdotal coaching practice, so find what works for you.
Each stride is 15 to 30 seconds up a moderate grade of 4-8%
Short duration allows athletes to maximize efficient output while avoiding recovery costs (or risking aerobic inefficiency) from longer efforts. 20 seconds seems to be a sweet spot. Some coaches do hill sprints that can be even shorter. The moderate grade is good to maximize output without crazy high or low cadence, or changed biomechanical patterns like you may see on a steep grade. But feel free to mix it up. If I ever robbed a bank, the wanted poster would probably say: “Last seen doing running up and down a random grassy knoll. Talking about pizza for some reason.”
Recoveries involve jogging back down and around until you are ready, usually 60 to 90 seconds, but err on side of more rest
Since the goal is not the aerobic stimulus, it’s better to recover more than to rush into the next interval. Other training systems will encourage even more recovery before short hills.
You can do 4 to 8 of them
We haven’t seen substantial long-term benefit from doing more per session. Instead, the benefit in our cohort of athletes is related to repeatability of sessions. Some training systems even have athletes do 10 to 20 short hills.
They can be added to almost any run, particularly the day before workouts or hard efforts
Because there is almost no recovery cost after an initial adaptation period, hill strides can be effective multiple times per week near the end of runs. In general, our athletes do them one to three times in a normal week, more often the day before harder efforts (or after harder efforts, as in a combo workout), and more often early in training than right before longer events. But probably don’t do them or other speed if you are dealing with any injuries.
Think strong strides, rather than the quickest turnover you can
Thinking about force maximization during the stride may be helpful for some athletes, even if it doesn’t fundamentally alter form in practice. We like athletes to think of it more like a bound for the first several strides, working into powerful and efficient running, rather than using quick little strides or sprinting out of the gate. One way to do that is to focus on knee drive.
Start relaxed and increase output, finishing with the highest output you can do without sprinting or straining excessively
Really ease in—that will decrease injury risk from speed changes, plus it will help key you into proper form. You don’t want these to be a sprint, which can increase injury risk and be less repeatable.
Hill strides will look different for each athlete based on background. That is OK! Don’t worry if you feel a bit awkward at first. Basically, if you’re putting out higher power up a hill, you’re doing it right, no matter what it looks like or what speed that is. You are rocking it, I promise.
Coolest of all: hill strides can be really fun. You may be shocked at how quickly you can get up your hill of choice, all without sprinting, feeling yourself getting stronger with each stride.
And maybe that’s the most important adaptation of all. Power hill strides are empowering.
David Roche partners with runners of all abilities through his coaching service, Some Work, All Play. His book, The Happy Runner, is about moving toward unconditional self-acceptance in a running life, and it’s available now on Amazon.