I receive lots of questions from athletes every week. They seem to come in topical groups. For some unknown reason this spring I’ve gotten a lot of questions from athletes who believe their heart rates are abnormally high during exercise and imply that they are concerned that they may have a cardiovascular problem. One guy even recently wondered why his heart didn’t explode. I don’t know if he was kidding but it’s the sort of thing many seem to be wondering this spring. So rather than continuing to reply to this same question repeatedly I thought I’d simply answer it here and then refer people to it when they query me. I also asked Dr. John Post, an old friend of mine and the Medical Director for TrainingBible Coaching, to comment from a medical perspective. He and I separately wrote a general reply. They seem to overlap quite a bit. So, here we go…
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Joe:
The first matter is to understand what “high” heart rate means. High relative to what? If it’s high referenced against the formula 220 minus your age then realize that this is seldom correct for anyone. If we found the max heart rates of a large group of people and graphed them we’d more than likely get a bell-shaped curve. There would be a lot of people in the middle for whom the formula was close, there would be some to the left end for whom the formula was too high (low normal heart rates), and to the right end of the curve would be those for whom the formula was too low (high normal heart rates). For people on the right end of the curve, chronically “high” heart rates while exercising are normal. They don’t have a problem, at least not based strictly on their heart rates.
Or if “high” heart rate means it’s high relative to your training partners' then this is essentially the same matter as the 220-minus-age formula. If this defines “high” then, in the absence of any other symptoms (such as light headed; nauseous; pressure, pain or discomfort in chest, arm, neck or jaw), you are probably good to go. You don’t have a problem. You just are on the right end of the bell-shaped curve.
These normal high or low heart rates also have no bearing on performance. I once coached a US National Age Group Time Trial Champion who broke the record for his age group. His 20k time trial heart rate was around 145. This didn’t slow him down. I also once coached a runner with a max heart rate in the high 210s. I’ve also coached athletes with big feet and little feet. None of these athletes had problems. They were just unique.
However, if the high exercising heart rate is unusual for you then you may indeed have a problem. But let’s further define “high” here. There are going to be days when your heart rate rises above what you normally see by perhaps 10 bpm or slightly more just because of fatigue, overreaching, overtraining, too much caffeine or similar product, or a hot day. This is not unusual at all. You may need to back off and slow down or even abandon the workout that day. This happens to everyone from time to time.
But if your heart rate is well above 10bpm over what you normally see at a given power, pace or perceived exertion (which may not work in this case) then you could have a health problem. But first check to make sure your heart rate monitor is working correctly and there are no errant signals.
Such an unusually high heart rate happened to me in 1994 while running a half marathon. Of course, as the dummy I am, I finished the race, albeit at a slower pace. After weeks of testing my doctor finally determined it was a case of viral myocarditis. That cost me seven months of training.
Another condition to be aware of is atrial fibrillation (“a-fib”). I won’t go into detail on this as you can read more about this here on Dr. Post’s blog.
So if you mean a “high” heart rate as one high relative to what you normally see at an otherwise common intensity and you’ve ruled out the heart rate monitor as the source of the “problem,” then see your doctor.
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John Post, MD:
Joe and I have received a number of queries recently about heart rate related issues observed in training so I thought a review may help answer some of these. This is a pretty broad topic so I’ll try to be brief. Let’s try to work from the answer backwards:
1) No two of us are the same.
2) No two of us fit the exact same formula/parameters relating heart rate to training.
3) If I see an unexpected indication, am I symptomatic?
“Balderdash,” you say. You’ve memorized the Triathlete’s/Cyclists’s Training Bible, understand the Borg scale of perceived exertion, and have constructed reproducible training zones. One initial fact that surprises many is that although your “athlete’s heart” resting pulse is probably around 60 or below, according to the Mayo Clinic, a normal resting heart rate can be 60 – 100. Yes, 100! And those of you on beta blockers as a part of your hypertension regimen will note a modest lowering of your natural base rate.
We athletes as a group pay a lot more attention to our bodies in general and HR in particular. And as such we should be familiar with the factors, in addition to exercise, that can modify our expected read out. Examples would be lack of sleep, fever, dehydration, anxiety, coffee (which you already know and manipulate), stress, general state of rest, just to name a few. Each of these could significantly alter that old Polar.
So, if you’re out on a routine training run over familiar territory you see a reading of 220, what do you do?
1) Use the old formula, 220 minus your age, and determine that you are dead?
2) Start self CPR?
3) Flag down a passing motor vehicle for a ride to the hospital?
4) Panic, wonder if your affairs and will are in order?
5) Call 911?
6) Rush home, post the symptoms on an internet forum and wait for guidance from an anonymous source?
7) Stop, think, and reasonably evaluate the situation?
Let’s use the scientific approach. If you’re symptomless, there’s no rush to do anything. An old saw from medical school is when you encounter an emergency situation, “Take your own pulse first.” If you’re not dizzy, in pain, feeling weak – especially on one side of the body, confused, etc. you have the ability to rationally evaluate what’s going on and exercise common sense.
It’s not uncommon to see what seems like bogus information be indeed bogus. Was this erratic reading due to nearby electrical interference, overhead power lines, nearby welding, lead placement or slippage, etc.? It’s unlikely that even if you were running with Kim Kardashian (ladies with Johnny Depp) that you could generate a heart rate of 220.
If, however, you do experience symptoms, or if it happens again, seek medical attention.

I've seen over 220 when coasting down hill on my bike early in the morning; thought the monitor was broken, but was picking up cold/shivering skin; as you say, evaluate the situation.
Posted by: Andre (Jamaica) | 03/13/2011 at 08:00 PM
I had a lone AF session 5 years ago when not in good shape. Did alot of research and found there is significant variation in what triggers AF in people. Some studies have shown an athletic connection. Since then I have become better trained and now often hit the podium in my AG (55). I have not had repeats of the problem, however at times I experience what Andre describes at cold bike or race starts, but it always returns to normal. The experience triggered me to learn more and clean up my act (eliminate caffeine, limit alcohol), and I always train and race with a HRM.
Posted by: Scott | 03/14/2011 at 09:06 AM
outside factors as mentioned above( fatigue, temperature, hydration) had a profound effect on my training session this weekend just past, conditions were warm with high humidity coupled with not enough sleep from working till 11 pm the night before, produced elevated HR's as much as 10% higher than i would normally expect for the same ride intensity(.83) and duration.. perceived effort was sky high as well, and power 5 watts lower, having built up a few months worth of powertap data now through both on rd sessions and wind trainer sessions, its amazing to see how much humidity effects performance. living in melbourne australia high humidity conditions are rare. My hydration plan i should have added min 1 extra bottle of fluid to my normal intake ,2 would have been even better for the above ride (130 km, 3hrs 55 min, 205 W)
Posted by: damian knightsbridge | 03/14/2011 at 03:33 PM
Dear Joe and Dr. John,
thanks for sharing this very useful article. We have been discussing this with the Master cyclist (55+) who have lately started to ride seriously. Many are afraid to take their heart rates at 160 to 170. The rule of thump 220-age seems to have stuck like glue. Also, back home (we are from Pakistan) there isnt awarness of sports and especially in this age Bracket the concept of Training Seriously or Scientifically is hardly there and the Doctors aint much Advisors for sports. (I have been advocating ppl to follow Joe's 20 min FTP test).
Joe - retquest to you that It would be of immense help if you could share the Bell Curve data for 55+yrs of athletes.
Dr. John, Please advise in medical terminology which Medical Test could these Master Category cyclist under take to give them assurace that they are not overdoing and the engine inside is capable enough to bear the load.
Thanks a lot.
U can check us out on FB "Critical Mass Karachi" http://www.facebook.com/home.php#!/group.php?gid=146496962679
Posted by: Rayomand Ghadiali | 03/16/2011 at 11:28 AM
Joe, i experienced a problem in the early 2010 season. All was going well for several months as i was training for a 12 hour solo mountain bike ride, and i was able to produce good power at 60-70% of maximum HR consisitently over 5-6 hours training. And then litreally overnight it all changed. My heartrate was all over the place and was at least 10-15 bpm higher then it had been. Racing was scary as it would sit at around 95% of maximum and didnt seem to recover. I mentioned this to my coach who said that because i was so used to training at Zone 2/3 i would naturally find it hard to maintain a high HR as i was accustomed to training for long distances at low HR's... I suspected i had been overtraining but had none of the usual symptoms ie sore throught, cold. As time went on i found it hard to even start a race let alone finish one....i just didnt have the energy. It ruined my 2010 season. Nobody could ever give me any answers as to why his happened i still suspect overtraining yet my coach insists this simply couldnt have been the case. My resting HR was always very low and still is... so why would your resting HR ( a good indicator of fitness) be low yet your working HR be unrealistly high?? Id be really grateful for some kind of answers??? thanks Andy
Posted by: Andy Paul | 03/19/2011 at 05:06 AM
Andy Paul - I wish I knew why. Good luck.
Posted by: Joe Friel | 03/19/2011 at 12:53 PM
Joe, how elevated was your heart rate during the race, regarding viral myocarditis? I'm not taking you for a doctor or depending on your answer, but am curious since I've been having a cold for 2 weeks now, and during lactate threshold spinning today (stupid, I know) my HR went to exactly 100% HRmax, 182 bpm after half an hour without too much work; normally I'd be at 93% or 170 bpm for that effort. I backed off directly and left, but watching a HR at 100% for 30 sec without feeling very tired was scary. No chest pain, feel fine, good power, no headache or throat ache, but a running nose, previous sore throat. I used two HR straps (one for class, one for me), both the same; no hardware failure. I'll get a ECG tomorrow. I know my HR responses/levels very well.
Thanks /P
Posted by: P | 03/29/2011 at 12:51 PM
P--It's been many years but if I recall right I was running it as a workout so pace was slower than would be expected for a half. But HR was well above LTHR although I didn't feel anaerobic in terms of breathing, etc.
Posted by: Joe Friel | 03/29/2011 at 01:18 PM
Dear Dr. P., your list is awesome. I love number six in particular:
6) Rush home, post the symptoms on an internet forum and wait for guidance from an anonymous source?
This at least, seems to me what a terrible lot of people do.
I read about an implant, which makes paralysed people moving computer cursors by thoughts. I am waiting for an implant for common sense...
Greets from Germany.
Posted by: exurei | 04/01/2011 at 11:49 AM
Joe, P here again, thanks for the answer, thought I'll write a follow-up; been to the doc, took an ECG and blood test (CRP, SR) to check for infections. All good; no infection, no myocarditis-looking ECG. Took five days rest, then did a test-run on the mill, that still shows HR climbing over LTHR to settle at 175, 96% MHR, when it's usually at 165, 90%. It didn't feel anaerobic, felt like just-below-LTHR, as the pace also was, but 96% is a serious effort for me, should feel much harder than it did. This seems familiar with what you've experienced during your myocarditis run.
So my question, still not depending on it as professional advice: your cardio doc told you to quit all training until the symptoms went away, 7 months in your case. What were the symptoms you were monitoring during those months? I'll take a break from training now, and would like to be able to look for indications that tell me when time is due to start again, slowly. The only not-normal-response I can see/feel is my pulse rising to higher levels than usually, and this can't be monitored during rest, of course.
Thanks Joe /P
Posted by: P | 04/04/2011 at 01:25 AM
P-What I experienced after the initial high HRs during runs was a slight pressure in my chest. But only occasionally. Felt like someone had the point of their finger against a rip just above my heart and pushing on it. This was transient. It took 7 months for that sensation to go away.
Posted by: Joe Friel | 04/04/2011 at 06:15 PM
Joe, I am from running background and switched to triathlons about 2 yrs back. My heart rate is always higher on the bike than when I am running. This is for racing and in training. Is there any explanation for this?
Thanks,
Etienne
Posted by: Etienne | 04/06/2011 at 10:30 PM
Etienne--HR tends to be higher (relative to effort) when we have less aerobic fitness in a sport and lower when fitness is better.
Posted by: Joe Friel | 04/07/2011 at 04:20 AM
Joe:
If you sample heart rates among people they will be distributed in a log normal distribution not a bell curve. It basically says that for example there are a few athletes that can run a sub 4 minute mile and lots and lots that can run a 6 minute mile. In rain drop size there are a very few large size and lots and lots of smaller ones. Mother nature orders things in a log normal distribution not a bell curve. A bell curve only means there are equal amounts either side of the mean but in log normal distributions it orders around the median which is the most common sample. Once you understand the log normal distribution a lot of things in life make more sense. Don't you hate engineers such as me? Thanks Joe and heal fast
Posted by: Glenn Sliva | 04/11/2011 at 06:41 AM
A 70 year old cycling mate of mine bought himself a HR monitor. When the monitor displayed his heart rate at over 200bpm he went to his doctor. Nothing wrong, but frightened off he discarded the monitor and never used it again. After some discussion with him it was my conclusion that his monitor was picking up his wireless wheel sensor for his bike computer.
As stated evaluate the situation.
Posted by: Brian | 12/13/2011 at 07:05 AM
Joe,
rather than having a high heart rate relative to my power zone I seem to be very low. Just re-established bike zones using the 30min test and having done an hour of Muscular Endurance 10 min intervals (Start of Base 2) my power zone was focused on zone 3 but never I even got into heart rate zone 2. Cycling is my weakest discipline. Is this an indication that my limitation is power which is falling behind aerobic fitness? Do I just stick with my power zones and worry less about the heart rate zones?
Simon
Posted by: Simon Kelly | 12/28/2011 at 05:13 AM
Simon--Wish I could help but there are just too many variables and not enough time.
Posted by: Joe Friel | 12/28/2011 at 03:00 PM
I am a 60 year old canoeist, trained most of my life and represented my Country when I was younger. My MHR has always been high and at my age I can still push my rate to 192. I can keep my rate at 180 for about 10 minutes . Am I abnormal or have you found other athletes that can do this.
My resting HR when I am really fit is 50. Your comments would be appreciated and thanks for your service!
Posted by: Saal | 03/17/2012 at 09:59 AM
Saal--I find this is common for older athletes who have maintained high levels of fitness their entire lives. I'm now 68 and my max HR is the same as when I was in my 30s. Keep up the good training!
Posted by: Joe Friel | 03/17/2012 at 10:41 AM
Thank you very much Joe for your comment! I thought I was up normal and feel much better now!
Posted by: Saal | 03/18/2012 at 01:14 AM
a question on heart rate and fatigue. Every season for the past 5 years I experience fatigue at mid summer. This includes high heart rate 15% higher than normal. I used a coach this year and the same thing happened. I was even riding quite a bit slower than any year in the past. Gained a lot of fitness from April til early June, caught a cold and took 5 days off the bike and haven't been the same since. I have fatigue in the legs and a very high heart rate that what I'm used to. Any thoughts? It's a bit depressing. My diet is vegetarian/vegan...does that have something to do with it?
Posted by: David S | 07/16/2012 at 06:34 AM
David S--I really can't say what you are experiencing, although it does sound like overtraining. It could be any number of other conditions. The symptoms of overtraining are similar to those of Lyme disease, mononucleosis, chronic fatigue syndrome, and others. If I was in your place I'd see my doc and talk about having some testing done.
Posted by: Joe Friel | 07/16/2012 at 06:44 AM
Hi Joe, I am curious to understand this about my heart rate. I can run a half marathon in 1:40 (ave HR approx 160). Recently, I did a 70.3 triathlon and kept my HR on the bike at average 155. I was feeling good coming into T2. I then started the run and consciously slowed down to get my HR under control as I knew I had a tough run ahead (hilly course). I was at this point going on feel, as the HR monitor was not reading correctly! But my HR wouldn't come down enough so that I could up the pace comfortably. I was hoping to finish the run in 1:45-50 but instead it took me 2:00. I was running all the time(bar two aid station stops). Why is this? Was I still going too hard on the bike or is it just a lack of fitness? How can I improve my run time?...I would really appreciate your thoughts.
Posted by: Nixer | 07/23/2012 at 03:22 PM
Hey Nixer-- I don't understand. You said your heart rate monitor wasn't giving you good data and yet you were concerned about your heart rate? Do you mean it starting working again later on? If so then you were just experiencing fatigue--or you were holding back artificially out of concern for HR. I'd recommend being less focused on heart rate in a race and more focused on how you are feeling. Heart rate is really not a good way to gauge intensity in a race.
Posted by: Joe Friel | 07/23/2012 at 04:16 PM
Hallo!
I have another problem - if i increase my training load, one day my heart rate start to drop - about 20-30 beats lower for the same speed (running). I have difficulties to increase heart for given load.
Is this normal and am i starting to overtrain?
Must i reduce my training load?
Posted by: Sandijs | 07/23/2012 at 11:18 PM