Is Heart Rate helping or hurting your training?
Exercise Physiology PhD, and 2:12 marathoner, Dan Nash, highlighting from his lab studies how unproductive and inaccurate Garmin’s generic heart rate zones are.
Is Heart Rate Helping or Hurting Your Training?
I have been running and coaching for a long time, and the thing that has always confused me the most is how much people obsess over heart rate training. I have a million thoughts on it, but let’s just start simple:
1. Why are you so sure that this specific heart rate, in these conditions, actually means anything?
2. Where did those numbers even come from?
Because here’s what I hear all the time from newer runners:
- “At 140 bpm THIS happens to my body.”
- “I saw my heart rate spike so I hit the brakes!”
- “Well, I saw this number in the workout/race, so I slowed WAY down!”
And look, I say this with all the love in the world and the sole intention of helping you get faster (I love you): I have been around hundreds of pros and elites, and I have never once heard one of them say something like that. The faster the runner, the less they care about HR. They know it is fickle. Heat, sleep, alcohol, stress, caffeine, training load—it all changes heart rate.
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Why Obsessing Over Heart Rate Can Hurt Your Training
One of the things that really scares me as a coach is when runners obsess over these numbers. I have watched plenty of athletes compete and train at heart rates I would have guessed were completely unsustainable for long periods of time. And yet, they were fine. Eventually I just stopped bumping up against that ceiling, because it was not useful or reliable.
At the end of the day the runner with the lowest heart rate does not win.
The Problem With Random Heart Rate Zones
Another thing I see all the time is runners just grabbing a random “zone” and throwing it into their training. Honestly, this can hold you back a lot.
If you are newer to running or coming off a decent break, it is really hard to get your heart into a true aerobic Zone 2 while still running at a normal pace.
Think about what running actually is. You are jumping on one leg, thrusting your entire body mass into the air and three feet forward, and then crashing into the other leg with up to five times your body weight. And then repeating that motion hundreds of times in a row.
If you have not practiced that skill a ton, if your bones, joints, and ligaments are not used to the pounding, and if your cardiovascular system has not spent years pumping massive amounts of blood, guess what? Your heart rate is going to be really high. Sometimes ridiculously high. You might be jogging so slowly that people are walking past you, and yet your heart rate is still through the roof.
And that is totally fine. That is normal. It does not mean you need to shuffle at a crawl just to “stay in Zone 2.” What it means is you need time. With consistent, smart training, your heart rate will eventually settle.
I have helped hundreds of runners figure this part out while still keeping good mechanics and improving methodically.
When Heart Rate Training Is Actually Helpful
So where does HR actually fit? For me, it is mainly just to keep easy runs easy.
Trying to nail down higher zones with heart rate? It is inconsistent, and does not actually tell you how fast you can race. And almost zero races happen in Zone 2.
Why Zone 2 Gets So Much Attention
A lot of the obsession with Zone 2 comes from the fact that when we run at that effort, there is less muscle breakdown and less lactate flooding the bloodstream that needs to be cleared. These are important principles when you are deep in high mileage training. You want to be able to run, say, 10 miles in Zone 2, get the aerobic benefit, and then come back the next day ready to crush a harder workout. If you keep your easy days truly easy, you stay fresher and can actually attack the hard days.
It also makes sure you are polarizing your training — getting plenty of true aerobic running and then real amounts of threshold or anaerobic work on the hard days. That separation is critical. The “gray zone” where it is all blended together is probably the biggest mistake most runners make, and it slows progress a lot.
But here’s the thing: most newer runners aren’t logging big mileage, they’re not running every day, and they’re not stacking massive workouts that demand perfect recovery. So the obsession with “never leaving Zone 2”? Honestly, it’s just not that important early on. In the beginning, it doesn’t matter if every single run is perfectly aerobic. What matters is finding an easy effort that feels comfortable and repeatable. Stick with it, build some training history, and your heart rate will settle down naturally with time.
The Real Skill: Learning How to Feel Effort
Here is the part I really want you to take away: every workout is a chance to learn your personal effort scale.
When you are running, ask yourself:
- Can I push a little more right now?
- Or am I already over the line and need to back off to finish?
- When is the right time to start pressing so I am empty at the finish, not halfway through?
And after the workout, reflect:
- Did I go too hard?
- Was it just right?
- Did I leave too much in the tank?
Every harder session is a chance to learn. To get better at allocating effort. To figure out what “too much” feels like. If you do this consistently, over time you will know your body so well that you can hit race effort without needing an overly prescriptive race plan.
The Bottom Line on Heart Rate Training
Heart rate is fine as a tool.
The real compass is effort. Learn your body.
Heart Rate Training FAQ
Do elites use heart rate monitors?
Some wear them, but generally they are used after the run to compre how heart rate matched up with their effort.
Is Zone 2 worth it?
Sometimes, yes, for easy days.
Why is my HR so high when I run?
Because running is hard. If you are new or just getting back into it, your HR will be high even slow jogging. Over time, it comes down.
Should I train by HR or pace?
Pace and effort are more reliable for most workouts. HR is fine for keeping easy runs easy, but it should not control your training.
Is HR training good for beginners?
It can help beginners avoid running too hard every day, but the real skill is learning what different efforts feel like.
🔥 Coach’s Tip: Let go of Heart Rate, Focus on defining your relative effort scale.
