Amber Sayer is a USATF-certified running coach, and has been training runners for 13 years. She holds two Masters Degrees—one in Exercise Science and one in Prosthetics and Orthotics, and is also a NSCA-Certified Personal Trainer.
As a runner herself, Amber has PRs of 17:07 in the 5k, 28:52 for 5 miles, 1:20:19 in the half marathon, and 3:01:02 in the marathon.
Amber enjoys working with runners of all levels and helping them achieve their goals.
We asked our readers to send her their training questions for her to tackle!
For this week’s installment of Ask Amber, we have three runners who have questions about their heart rate or heart health.
Question 1: Heart Rate During Long Runs
I have a question I hope you can answer either in your column or just via email. I’m at a complete loss!
I hear a lot about long slow distance for building endurance, and that the long runs should be done while keeping your heart rate in zones 2 or 3 (at least on the Polar 5-zone scale), which for me is between 112 and 149 bpm (60-80% of max). However, I zip right through zone 2 within a minute and zone 3 within another 5-10 minutes, ending up in or near zone 5 by the end of my run (I’ve added the chart below from my last long run this weekend).
My “normal” pace is about a 12-minute mile, as I just started running this spring. For the “long” run (currently only 4 miles), I’m averaging somewhere around 13-13:30 per mile (the one below was at a 12:52 pace avg). Even on my slower long runs around the 13:30+ mile per minute pace, I’m unable to keep my heart rate in the correct zones. If I go much slower I’ll be walking! Can you please tell me how to keep my heart rate in the target zone on these runs?
Any guidance you can provide would be greatly appreciated!!!
Jim Smith, Greenfield, IN
This is a great question and one that I’m sure many other runners are experiencing as well.
My first question back to you would be: how did you determine your heart rate zones?
If you did an actual maximum heart rate field test, there is more to look at, but I’m guessing that you might have used an age-predicted maximum heart rate formula to set your heart rate zones.
Any of the formulas that estimate your maximum heart rate are simply that—estimations— and most have at least a standard error or standard deviation of +|- 12-15 beats per minute.
For example, the Fox Formula for Age-Predicted Maximum Heart Rate (220 – age in years), which is the most commonly used formula for calculating maximum heart rate, has a standard deviation of about 12 bpm in either direction.
What this means practically is that your heart rate zones can be pretty far off if you are indeed one of the many outliers.
I don’t see your age given in the email, but from the looks of the heart rate data you sent, it looks like your maximum heart rate is set at 186 bpm.
Assuming you used 220 – age to derive that number, you are 34 years old.
Let’s say that your true maximum heart rate is one standard deviation (12 bpm) above the norm (and it might be more than that!).
This would put your age-estimated max heart rate up at 198 bpm, and would shift each of your heart rate tones rather significantly.
I’ve calculated your new theoretical heart rate zones as follows:
|THR in bpm
|178 – 198
|158 – 178
|139 – 158
|119 – 139
|99 – 119
Although these numbers may not be exactly true for you, the point remains that depending on how you arrived at your heart rate zones, they might be quite far off.
I would recommend trying to do a true field test to measure your actual maximum heart rate.
Here is a simple way to do so:
Here is a field test to measure your maximum heart rate:
- Warm up by running 1-3 miles depending on your fitness level (1 mile will work for you).
- Run one mile on a track at tempo pace, but with 400 meters to go, ramp up to an all-out effort.
- Sprint the last 100 meters as fast as you can.
- Review your heart rate data from the last 400 meters and the highest number recorded is your maximum heart rate.
If you indeed did establish your heart rate zones based on a true maximum heart rate test, you may need to redo it now that you are fitter.
It sounds like you haven’t been running for very long (welcome to the club!), so your fitness might have progressed significantly since you first established that number.
It might have been the case that you were so winded and accustomed to running when you did your first maximum heart rate measurement that you were unable to push yourself to a true maximum.
Either way, your data tells me that these heart rate zones may need to be reset for you.
I’d be really curious to see how your heart rate trends once we have more accurate heart rate zones. If you are willing, please let us know if you are able to redo your zones and then see where your heart rate lands during a long run.
As one final note, your long runs do seem a bit fast relative to your “regular“ training pace.
You want your long runs to be about 90 to 120 seconds per mile slower than your race pace.
I’m not sure if you’ve run a race yet, but if you feel like your training runs are pretty high up there in terms of the intensity you are running, your long runs might still be too fast.
Finally, you might enjoy looking into the Maffetone method. We can explore this further after you’ve recalibrated the heart rate zones, or you can read more here.
Please keep us posted!
Question 2: Low Blood Pressure
What are the pros and cons of low blood pressure? And how can low blood pressure impact your running?
This is a great question. We often hear about the risks of hypertension (high blood pressure), which makes it seem like hypotension (low blood pressure) Is always a good thing.
However, as you pointed out in your question, there can be pros and cons of low blood pressure.
Generally speaking, hypotension is considered to be a blood pressure reading of anything below 90/60 mmHg.
If your blood pressure is just a little bit low, you probably won’t notice very many side effects, but once you are truly hypotensive, your exercise performance will certainly suffer.
You can feel dizzy, lightheaded, weak, sluggish, nauseous, and fatigued.
All of the symptoms will, of course, negatively impact your performance because you won’t feel strong and hale as you run.
Runners tend to have relatively low blood pressure due to the cardiovascular benefits and decreased arterial stiffness induced by habitual running, but running itself will elevate your blood pressure during the activity because your heart is forcefully ejecting more blood through your arteries in order to oxygenate your muscles.
Overall, having low blood pressure reduces the risk of cardiovascular events like heart attacks and strokes, but benefits of low blood pressure are only considered healthy above that 90/60 mmHg threshold (so something lower than 120/80 but higher than 90/60).
If you are noticing that your blood pressure is routinely too low, try increasing your fluid intake and adding electrolytes. Sodium will help you retain more water.
Consult your doctor if you are experiencing concerning symptoms or chronic hypotension.
Let us know if that helps!
Question 3: Resting Heart Rate
I hope you’re able to answer my question. I am training for a half marathon in October and have noticed my heart rate when I wake up keeps getting higher. I have heard running lowers your heart rate so I’m not sure if it’s getting faster. Should I be concerned? How long does it take to get lower?
Henry Chen, Manitoba, Canada
Thanks for the question.
You are right in the fact that habitual aerobic exercise can lower your resting heart rate because the heart becomes stronger and more efficient at pumping blood to your body. Stroke volume increases, enabling your heart rate to decrease while still meeting your cardiac output needs.
Resting heart rate is affected by factors such as your age, sex, training status, hydration levels, smoking habits, genetics, stress, and medication‘s that you take.
If you are noticing that your resting heart rate has been increasing, it can be a warning sign of overtraining.
During recovery from exercise, your sympathetic nervous system has to work harder to restore homeostasis and bring your body back to resting conditions.
Your heart beats faster to circulate enough oxygen and nutrients to your skeletal muscles to repair damage and promote recovery.
There are hormones produced during physical activity, such as epinephrine (adrenaline), that stimulate an increase in your heart rate.
When you are fully recovered from a workout, your tissues have received adequate perfusion and your hormones should have returned to resting levels, so your resting heart rate returns to baseline.
Although the recovery from a workout typically takes a couple of hours, when you are overtrained and under-recovered, this process gets drawn out.
Chronic overtraining can leave the body in a state of incomplete recovery, which can be reflected in a higher resting heart rate.
I would suggest looking at your training and critically evaluating if you’re overtraining, under-recovering, or underfueling.
Keep tabs on how you’re feeling and let us know if some extra rest days and backing off a bit gets things trending in the right direction!
Send us your questions! Email Amber at firstname.lastname@example.org.