Running has several metrics for improvement. The clock, the track oval, mile marker, GPS running watch, and even the bathroom scale are frequently used as measuring sticks for fitness and health. But how do we know if our bodies are positively adapting to our run training, and doing so with decreased stress and enhanced health?
As a runner of 20-plus years and a coach for 15, I have but one reliable tool: the heart-rate monitor. It is all-knowing. Nothing can hide from it.
But using a heart-rate monitor to guide training has its challenges and pitfalls. After several years–and a lot of trial and error–I present the following concepts, challenges, and tips for using the heart-rate monitor in ultra-trail training and racing.
The author monitoring his effort while on a Central Oregon trail run. All photos: Joe Uhan
Heart Rate and Its Meaning
Since the dawn of exercise-physiology study, heart rate has been known to correlate with overall system output, or response to activity. The harder we work, the faster our hearts beat. It is our best measure of how hard the system is working to produce energy and, simply put, keep us alive. And like the stopwatch or mile marker, heart rate can be used as a measuring stick of energy output and performance.
But unlike the watch, heart rate takes into account a third dimension: stress. Since the body and the heart must also adapt to non-running stress, our lifestyle off the trail–work, family, sleep, nutrition–becomes an input affecting heart-rate output.
Moreover, heart rate also factors in external variables like heat, humidity, and altitude. The heart beats harder and faster in adverse conditions.
In short, heart rate is an extension of the Central Governor, factoring in everything going on with our bodies inside and out to determine how to best keep us going!
This is what makes heart-rate monitoring so interesting. And, at times, painfully frustrating.
Heart Rate as the Running Coach
Heart-rate data has two primary uses:
- To ensure one is running easy enough on aerobic (and recovery) runs; and
- To ensure one is running hard enough in workouts and races.
Without delving too deeply into exercise science, aerobic running is required to enhance fat metabolism and aid recovery, while high-intensity running is crucial for strength development and race-specific adaptation.
Seems pretty simple, so why use a heart-rate monitor? We are creatures of habit. Humans crave routine and consistency, and too often runners unknowingly run neither easy nor hard. Instead we naturally run somewhere in between. Unfortunately, when we spend to much time in this “gray zone,” we don’t get the proper aerobic fat-burning fitness or recovery, and we don’t run hard enough to maximize strength.
The heart-rate monitor thus becomes a de-facto coach that instills discipline on both ends of the training spectrum.
Heart Rate as the Measuring Stick of True Fitness
People love running because, unlike most other sports, if you work hard, you invariably improve. This is the quintessential training response: run long and hard, and the body will adapt to run a little longer and faster the next time.
However, it is easy to take advantage of, if not abuse, that adaptation, for adaptation does not necessarily equate to enhanced health. Indeed, the body will adapt to even the harshest, most unhealthy habits (like smoking), but that does not mean such adaptations lead to good health.
So how, then, does a runner know she or he is enhancing fitness and health?
In response to this question, and seeking to find the path toward holistic health, endurance-fitness gurus such as Phil Maffetone have for decades been advocating heart rate as the most reliable metric for fitness development, and his Maffetone 180 Formula Method and others are gaining a greater foothold in ultra-endurance training, for good reason: heart rate represents the best measuring stick of true fitness improvement.
It’s simple: running faster at the same heart rate or running the same pace at a lower heart rate equates to greater fitness. It is efficiency defined. The body does more with less.
Without a heart-rate measure, there’s no saying why we run faster. Are we becoming more metabolically or mechanically efficient, or are we simply pushing our bodies harder and farther?
The Challenges and Pitfalls of Heart-Rate Training
So it’s settled, then. We should monitor heart rate, stay in our zones, and we will all eventually rise to max-fitness utopia, right? It’s not that easy. I’ve been a proponent of heart-rate training for several years. I advocate and actively use heart-rate training personally and as an ultra-endurance coach without exception. It’s been invaluable for my and my clients’ training, but it has its challenges.
Heart-rate training is a major paradigm shift. Runners are creatures of habit with deeply-entrenched belief systems. Even if they buy into the theory, it can be a shock when the heart rate hits their prescribed ceiling and they’re a good one, two, or even three minutes per mile slower than their “easy pace.” Heart-rate training requires buy-in and a letting go of often long-held notions of what it means to run easy, medium, and even hard paces. The playbook is rewritten.
If your life is out of balance, there is nowhere to hide. Because heart rate is an extension of the Governor, if the non-running side of life is strained–too much work, not enough sleep, poor nutrition–it will show up in the heart rate and you will have to slow down. Type-A runners used to running their clockwork pace are in for a major shock, especially when (often due to fast-rushing stress hormones!) they “feel just fine,” only to see the monitor hit the roof at the slowest shuffle.
What does it mean? Are these variances dismissible? Several prominent coaches will downplay or dismiss these “spikes” as being irrelevant to the actual physiology. But I disagree. The body predetermines energy selection holistically. So if you’re stressed out, it’s going to push you to anaerobic (to access that fast-burning sugar fuel) at a much slower pace than if the other systems are restful, simply because the system thinks you need that energy system!
Heart rate doesn’t care how pretty the trail is or your level of stoke. Beyond the internal, heart rate is highly sensitive to the environment. Heat, humidity, and altitude are major inputs to the system as are the demands of elevation and tread. This is a huge issue for trail runners, who will stress their system much harder, for much longer, on a beautiful trail among friends than they would on a flat, neighborhood bike path.
But the system doesn’t care. It perceives a great challenge, and will rev the system to deal with it. As such, the metabolic cost of a “medium four-hour trail run” may be similar to a road-marathon race of the same duration. While the muscle stress may be less on the trail, the internal stresses–including the neurological and immune system–may be entirely anaerobic.
It’s not uncommon when excited and amidst great beauty to log heart-rate values such as these, yet claim the effort “feels easy.” This is commonplace at events such as Western States, which features a four-mile mountain climb at altitude at the race’s onset.
While the brain may not register that pain, heart rate does.
Heart rate doesn’t care about the fun group you’re running with and the great conversation. The true gift of running is sharing it with others, and often in a group we will roll along at a strong pace, the conversation flowing, with nary a care about the effort. Indeed, the distraction from the effort is a big reason that we run in groups.
But while our consciousness might be distracted, our heart rate isn’t missing anything. Hard running is hard running and often, when we’re chatting away, our breathing becomes compromised–or we get worked up about an issue–and the system might get revved even higher. As such, many adherents of heart-rate training have to curtail their group running to either run with slower runners or alone. And because many of us run in order to socialize, this can have tremendous consequences.
Being anxious about your heart rate and pace… only makes heart rate and pace worse! So let’s say, despite all that buzz kill, you’re still committed to heart-rate discipline. You dutifully strap the monitor to your chest. Each day you ease into your running, hoping that “today’s the day” you will run fast with a low heart rate. But it never happens, does it? You check your wrist. Every. Ten. Seconds. But today? You’re even slower! The result: you get angry. Anxious. You question. “Am I running too fast? Sick? Tired? Weak? Just a terrible runner?” But anxiety begets a higher heart rate!
And so it goes, the anxious runner gets stuck in the “slow pace, high-heart-rate vortex.”
Finding Compromise: Balancing Holistic Fitness with Running Enjoyment
Heart-rate training is a tough taskmaster. It is a brutally cold, depressing Santa Claus. It sees you when you’re sleeping, it knows when you’re awake (or stressed, or eating poorly), and it darn well knows if your training has been bad or good. But there is a way to use this powerful tool without being beaten down. Here are some tips for striking a balance:
Commit to at least two to three months to rewrite the system. Heart-rate training takes a true commitment, and if you’re new to it, taking a new approach, or coming back from burnout or injury, it will be a significant change.
Find your heart-rate zone and stick to it for two to three months, akin to “base-building.” Do whatever it takes to stick to that heart rate no matter how painfully slow it may be. Within a few days, you’ll get a good idea of what this foundational pace is. Accept it, check the ego at the door, and commit to that effort for at least two months. It will take at least that long to “re-wire the system” and to begin to see real improvements in fitness.
Meanwhile, commit to addressing the other aspects of your life: family and work balance, relationships, sleep, and nutrition. These variables weigh heavily in your training response. Fast, sustainable running depends on finding true balance.
If properly executed, within several weeks you’ll see distinct improvement in your pace at a given heart rate. For example, one of my clients, whose marathon PR was 3:05–but who was hampered with chronic injury–had to initially slow to 10:30-minute miles. But within three months, he was running sub-nine-minute pace. And two years later, his pace–at that same heart rate–is now close to eight-flat pace or faster, with several ultra finishes and a recent equaling of his marathon PR.
Figure what what true aerobic pace feels like. We all have a notion of what easy pace is, but it is often arbitrary and, in many cases, wishful thinking. “If I run everything a little faster, eventually it will feel easier.” Unfortunately, this seldom leads to sustainable fitness gains–thus the heart-rate approach. Once you commit to a maximum-aerobic heart rate, learn what true easy feels like.
What I tell my coaching clients is, easy, max-aerobic pace should feel like “all-day pace,” akin to 100-mile race pace. It is a pace that–at least in the initial stages of heart-rate training–should feel absolutely effortless. In time, your body and brain will truly learn what easy pace feels like rather than the arbitrary grinding base pace previously run. Your previous “easy runs” will now feel like a grind–as they should!
Find and mind your hard-work paces. Depending on your training goals, the next phase of training might include anaerobic threshold and/or higher-intensity, VO2Max intervals. There are myriad resources out there to help determine these paces, including percent-max-heart-rate zones. I like to use an adaptation of the Maffetone calculation:
Max Aerobic: 180 Minus Age
Anaerobic Threshold: 200 Minus Age
VO2Max Pace: 210 Minus Age
While these values (and training strategies) are highly debatable, once you have a set point, stick to these zones in your workouts. These zones will serve as a governor and anchoring point. Then, when your training performances improve, you will know you are training sustainably. Stagnation or regression of paces-per-heart rate (at similar conditions) is a sure sign you are overreaching.
Once you know your easy, “turn away” from the monitor and run by feel! After a few months of disciplined heart-rate training, you will learn your true aerobic pace. If you’ve ever been caught in the anxiety vortex, it’s now time to turn off the monitor and just run! Run easy, be relaxed, run joyful, but above all, be honest with yourself! Run EASY. Check heart rate sparingly if at all, and only make a note of it at the end of the run. Frequently runners will report they will run faster at an equal heart rate simply because they quit worrying about it and just ran!
So long as you’re running close to your zone, you’ll be getting all the training benefits anxiety-free!
Run with a group as your threshold run! For more than one runner I’ve coached, the breaking point of heart-rate training is the loss of camaraderie from avoiding the quick-footed running group. Once base phase and injury rehab goals have been met, go back to the group, but recognize that these runs are now workouts!
If the weekly group run is six to 10 miles, consider doing five to 10 minutes of slow warm-up at your aerobic pace prior to starting with the group. Then grind and chatter away, occasionally checking the monitor to be sure you’re staying within threshold. The next day, be sure to take a slow recovery day.
Be patient, and your fitness will sustainably grow and surpass your former self. Maintain your commitment to keeping the majority of your miles truly easy. Run hard-but-disciplined workouts, and monitor your results to be sure you’re progressing with the same or lesser heart rate. In time, your easy (and workout) pace will progress, until it equals and then surpasses your previous self. And with any luck, you will find yourself breaking beyond previous training and performance plateaus to new heights.
Final Thoughts
True aerobic, heart-rated-based training isn’t for the faint of heart. (Pun intended.) It is hard work, requiring great patience and discipline. But for those interested in peak performance and sustainable, life-long running who commit to the process, the payoff is tremendous: bigger miles, faster recovery, next-to-no injuries, and peak performance with fewer problems. My hope is that these tips will help you navigate the challenges of heart-rate training and keep you committed to the type of training that will keep you running long for a long time to come!
Call for Comments (from Meghan)?
- Do you run with a heart-rate monitor? When did you start doing so and for how long have you trained this way?
- For those who started heart-rate training after running “by feel,” what did you learn about your previous paces and how did your paces change for your various heart-rate zones?
- If you have used heart-rate training for a lengthy period of time, how have you observed your heart rate change in reference to your training and other life factors like work, family, and aging?
