Athlete struggling to increase heart rate

[jd2002]

Hi.  I've now owned my fitbit charge for about a week and really like it.  I'm a female, in good shape and exercise avidly.  My body fat is in the "athletic" range (14%)  and my resting heart rate sits around 43bpm.  I'm noticing that when I'm exercising, even with very high intensity, my heart rate registers around 120bpm.  I am going all out.  Exercises include crossfit (metcon workouts) and HIIT workouts on the elliptical (60 seconds all out 4 minutes slowing down but still exerting effort).  Does anyone else experience this or have suggestions for getting my heart rate up?  Would this be considered elevated since my heart rate is so low?

[trainer]

You are going to have to really increase your intensity to get your HR up simply because you are in such good shape. It is also going to drop very quickly once you slow down so it will be harder to capture your top HR. Finally, there have been several reports that the HR reading on the fitbit has trouble when you are really going all out. My suggestion is to find a chest strap monitor and use that to see what your HR is doing on a device that is very good at picking up true HR (polar makes an inexpensive one that is easy to find in most sports stores and is very reliable) and compare that to your fitbit. Finally, if you are still not able to get your HR very high check with a dr. Some meds and supplements can suppress your HR so that you really can't get it very high.

[reuel]

you could try sprinting until you feel like puking. go all out and do not leave anything on the tank. it might take awhile (5 minutes or probably more) cause you are pretty athletic, but everybody has to have their limits

[Xyrus]

I'd need a little more info before making any recommendations. Height, weight, and age are all important factors when it comes to heart rate.

But first, if you can, compare the measurement against a chest strap monitor or even just checking your pulse to make sure there is an issue.

If there is a discrepency, you may also want to make sure no extra light is seeping underneath and getting to the sensor, as that can also throw it off. You can try wearing a couple wrist bands (one on each side) snug to the device to help block light seeping under. This will also reduce any ambient light penetrating your skin near the device.

Also, wearing the device high up on your wrist and tight helps as well. Thicker tissue, better contact.

I doubt you're an ape like me so arm hair probably isn't a problem for you. But since I wear mine all the time I actually clear a little patch where the sensor sits which also helps. So far the profile pretty much matches my old chest strap.

If the device appears to be accurate, then you may be in good enough shape that even though you think you're going all out your body doesn't agree with you. I notice you mention a lot of "bursty" activities but not much sustained. Try a three mile run or something, and set a good pace to get your heart pumping.

If you still can't seem to get heart rate up and you have symptoms like lightheadedness, fatigue, etc. not related to working out or your heart rate range is excessively low for your age/height/weight then you may want to check in with your doctor to make sure you don't have some form of negative bardycardia or a condition inducing bradycardia. This is very unlikely however.

[Colinm39]

@jd2002I agree with @trainer. I use a Polar for the reason you want to check.. I'm no athlete, but with a RHR of 51, but yesterday it was 46 so I have the same problem.  My maxHR should be 147 at my age and when I exert myself I cannot test my pulse unless I use the Polar.... My HR recovery is too fast..

I use the Polar to keep the Fitbit HR's honest because I have all the same issues with their variable HR that you read in the posts. I find they do a good job for the brisk walking and as one Fibitter said "they are perfect for the 75+ group" which is me.....

[Heybales]

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@jd2002 wrote:

Hi.  I've now owned my fitbit charge for about a week and really like it.  I'm a female, in good shape and exercise avidly.  My body fat is in the "athletic" range (14%)  and my resting heart rate sits around 43bpm.  I'm noticing that when I'm exercising, even with very high intensity, my heart rate registers around 120bpm.  I am going all out.  Exercises include crossfit (metcon workouts) and HIIT workouts on the elliptical (60 seconds all out 4 minutes slowing down but still exerting effort).  Does anyone else experience this or have suggestions for getting my heart rate up?  Would this be considered elevated since my heart rate is so low?

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The estimate of HRmax that creates those zones can be very inaccurate - you have more chance of being outside the calculated by 10 bpm then being within. And for women, the bell graph is even worse.

Mine calculated with 220-age they use would be 174. Mine tested is 194.

Some people have Honda hearts, some people have diesel hearts - that's genetics and more exercise won't change it.

Exercise just prevents it from lowering with age as much as commonly expected by average people.

Now truly endurance trained cardio, like ultra-marathoners and TdF bike riders, do have lowered HRmax after their specific lower end training to maximize fat usage and aerobic HR zone.

But if this in shape, perhaps you are ready to graduate to a HRmax test if you think your Dr would approve, or since you are already attempting to, probably not an issue.

This will also help give a decent estimate of VO2max, and better calorie burn estimate.

Here is test.

http://www.myfitnesspal.com/blog/heybales?month=201403

Also ditto to advice the Charge HR is probably not reading the upper HR's correctly, and this test should NOT be done using anything but EKG accurate chest strap. Bad results are useless results, don't waste the effort.

And yes, the HR zones based on resting HR (which Fitbit may/could use since they know it) and HRmax are the best.

www.calculatenow.biz/sport/heart.php?

Sadly I don't know if there is a way to adjust Fitbit's zones with better stats.

But once you know the split numbers, you really only need to know top of fat-burning zone for when you are doing recovery cardio, top of aerobic for most training for endurance, and really interval training is all out, so it really doesn't matter what the range is - pushing as hard as you can is it.

Though, 60 seconds is rather long for true HIIT, about 45 max for you being in shape would allow pushing harder the whole time, and recovery of 3 x as long, 135 sec.

[jd2002]

Thanks everyone for your ideas.  Heybales:  I'm not sure how much you know about the test you suggested, but I had some work done last year due to my low heart rate (I have pauses at night of 7-9 seconds when sleeping), which the doctors attributed to my good physical condition.  When I went back to look at the papers, they mentioned the "Bruce Test" which was what your link suggested.  My results showed that when running on an incline I can get my heart rate up.  I just don't know how to interpret them in relation to my workouts.  Results are as follows:

The patient exercised on a Bruce protocol for 13:14 min:sec achieving 150 % FAC.

The patient achieved 14.2 METS with a double product of 28728.

The target heart rate is 159 BPM, which is 85% of the maximum predicted heart rate.

The heart rate response was 69 BPM at rest to 171 BPM at peak stress.

Peak heart rate was 171 BPM, which was 91 % of the maximum predicted heart rate.

Blood pressure at rest was 118 mmHg/71 mmHg.

Blood pressure at peak stress was 168 mmHg/50 mmHg.

Normal blood pressure response to stress.

O2 sat at rest 100 %, and with exercise 98 %.

The patient experienced no cardiac symptoms during stress.

My other stats:  I'm 5'4", 118lbs, 33 years, female, body fat around 14%.  I've done cross country and track since highschool and have been active every since.  I exercise a minimum of an hour a day, but am also training for a marathon, so twice a week, I'm putting in more time than that (on my long runs, my heart rate gets up to 130's).

One final thing:  Should I just go back to running if that's the only exercise I can elevate my heart rate in (get off the eliptical or HIIT style workouts)?  Or am I overthinking this?  The monitor is making me obsessive 🙂

[Gershon]

I've never been able to get my heart rate above about 125. That's about 80% of my max heart rate, I think. I'm not sure how the numbers work as I get older. 

Since your resting heart rate is so low, I wouldn't worry about it. You are in great shape. 

[chrisxr2]

Try skipping (jump rope) my resting hr I is around 47bpm, I hit about 170 peak whilst skipping at max effort.

[Heybales · Accepted solution]

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@jd2002 wrote:

Thanks everyone for your ideas.  Heybales:  I'm not sure how much you know about the test you suggested, but I had some work done last year due to my low heart rate (I have pauses at night of 7-9 seconds when sleeping), which the doctors attributed to my good physical condition.  When I went back to look at the papers, they mentioned the "Bruce Test" which was what your link suggested.  My results showed that when running on an incline I can get my heart rate up.  I just don't know how to interpret them in relation to my workouts.  Results are as follows:

The patient exercised on a Bruce protocol for 13:14 min:sec achieving 150 % FAC.

The patient achieved 14.2 METS with a double product of 28728.

The target heart rate is 159 BPM, which is 85% of the maximum predicted heart rate.

The heart rate response was 69 BPM at rest to 171 BPM at peak stress.

Peak heart rate was 171 BPM, which was 91 % of the maximum predicted heart rate.

Blood pressure at rest was 118 mmHg/71 mmHg.

Blood pressure at peak stress was 168 mmHg/50 mmHg.

Normal blood pressure response to stress.

O2 sat at rest 100 %, and with exercise 98 %.

The patient experienced no cardiac symptoms during stress.

My other stats:  I'm 5'4", 118lbs, 33 years, female, body fat around 14%.  I've done cross country and track since highschool and have been active every since.  I exercise a minimum of an hour a day, but am also training for a marathon, so twice a week, I'm putting in more time than that (on my long runs, my heart rate gets up to 130's).

One final thing:  Should I just go back to running if that's the only exercise I can elevate my heart rate in (get off the eliptical or HIIT style workouts)?  Or am I overthinking this?  The monitor is making me obsessive 🙂

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So it sounds like the test was the result of the low HR noticed, what they wanted to do to check it out?

That appears to be the sub-maximal stress test to start with.

They estimated HRmax based on something, usually better than 220-age. Then took 85% of it as goal to initially reach, about top aerobic level or lactate threshold, depending if they included resting HR in estimate.

If they found no problems up to that point, they let you keep going - which it appears you really did.

And while your tested HRmax was lower than they predicted, just means their prediction was bad - it's nothing that more exercise will help obtain, or even that you would need to.

Now, did you take a rest day prior to that test? If not, HR could have gone higher, should have had rest day.

So HRmax is 171, you got resting HR - use that link I gave you above if you want to do any kind of HR zone training - and frankly you should if doing marathon training.

And I think I know why you can't get the HR that high normally in your workouts. Because your zones should be higher for training on the days that need it.

Exercise done to improve the body, if done right, breaks it down.

It's the rest for recovery and repair that allows building it back up - stronger if diet allows.

Where is your rest for recovery and repair?

Minimum 1 hr daily, 2 x weekly much longer runs.

Even if cardio isn't like lifting where there is a pretty clear 24-36 hrs for repair, doing every day workouts, especially if they are as hard as you can, thinking that better, you just have plain tired muscles - likely on the way to an injury.

Tired muscles can't push your HR that high.

You don't have the body you had in high school, nor that ability to recover so fast, though I'd wager even that was extreme compared to the few good coaches teaching running. Ours was not.

The low BF for a woman is actually a stress too, since body naturally doesn't like it that low.

Also, you can't do true HIIT on a machine, though I'll admit elliptical is better than treadmill, since you can just increase the speed by yourself to max. On treadmill that ability to punch up the speed is too slow, and it likely is not truly max, ect - not really HIIT.

But why are you doing the HIIT on the elliptical if running is the training you are doing?

I sure hope you don't say for fat loss.

HIIT is as close as you can get to lifting doing a cardio workout, for those that don't want to lift, but want to increase muscle for their cardio sport.

Elliptical HIIT isn't going to help you on the road at all, wrong muscles used.

If you want a killer HIIT routine for running, using a track, let me know.

But the cross-training is great, I'd suggest making it fat-burning zone, better called Active Recovery HR zone for the years prior to the fad name starting.

And allow it to follow and preceed strong running days, either in intensity or duration.

Just picture the HIIT workout since you are familiar with it.

Think of top speed reached during the hard part.

Now what if the workout was this.

45 sec as hard as possible.

45 sec as hard as possible.

45 sec as hard as possible.

45 sec as hard as possible.

45 sec as hard as possible.

Do you think you have any hope of that last 45 sec part actually being as fast or as hard as the first one?

Even though you could be giving it your all and it felt just as hard, the results are obviously different.

Now look at your weekly workout schedule. What do you do, and at what intensity?

Tired muscles can't push the heart hard enough.

And since at higher reaches of fitness, improvements will take better workout arrangements.

If truly the Bruce protocol, your VO2max is estimated at 54 mL/kg/min.

If you lost weight since that test and maintained fitness level, the VO2max actually went up.

[Colinm39]

@HeybalesThis test is the same as I had a few years ago and they put my missing heart beats down to body fitness from my younger days and they also  blamed parents genetics. The cardio specialists weren't worried and said what I had was more common than one imagines and normally in athletes. The annoying part is that if  sleeping on my left side when my HR gets around 42 the missing beats wake me.

[reuel]

if running stresses out your knees try boxing or kick boxing. if 5 rounds of explosive footwork and attacks won't get your heart rate up, you probably should consider competing lol you'd be a cardio monster

[jd2002]

Thanks Heybales.  I followed up with the heart rate zone website and with my numbers, my "fat burning zone" is about 20 beats per minute below the estimated fitbit average for a woman my age.  This makes me feel a lot better about my training.  Hopefully fitbit will soon allow for customizable heart rate zones (rather than just a min and max).

Also, great points about the fact that the cardiovascular system is a muscle that needs "rest" as well.  The eliptical work is what I tend to do on rest days for my psychological health (thinking more about the non-impact component rather than the cardio component); however maybe a complete break would be a better idea in order to allow my body to recover.

[Heybales]

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@Colinm39 wrote:

@HeybalesThis test is the same as I had a few years ago and they put my missing heart beats down to body fitness from my younger days and they also  blamed parents genetics. The cardio specialists weren't worried and said what I had was more common than one imagines and normally in athletes. The annoying part is that if  sleeping on my left side when my HR gets around 42 the missing beats wake me.

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Curious, does it also beat harder since so low a HR?

Doesn't hit me all the time, so not sure why, but it's still low but pounding much more, and that will wake me, or keep me awake.

Never noticed missing heart beats though, and didn't realize that common. I know some Dr's freak out over even the 40-45 HR range.

[Colinm39]

@HeybalesMy heart beat is normal.  In a brisk walk. 3.8 mph it sits at around 100 and then up a gradient around 110-115 bpm. When I do some HiiT walking it gets to 130 but no feeling of the heart wanting to burst out of the chest or my ears.

 I passed my annual medical with flying colours and the doctors smile when the HR misses a beat.  They tell me it just misses the 0.2 second timing and nothing to be of concern.

[Colinm39]

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@Colinm39 wrote:

@HeybalesMy heart beat is normal.  In a brisk walk. 3.8 mph it sits at around 100 and then up a gradient around 110-115 bpm. When I do some HiiT walking it gets to 130 but no feeling of the heart wanting to burst out of the chest or my ears.

 I passed my annual medical with flying colours and the doctors smile when the HR misses a beat.  They tell me it just misses the 0.2 second timing and nothing to be of concern.

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@HeybalesI also keep an eye on my recovery HR and the difference between the HR when I stopped the activity and 2 minutes later. It is typically 7-9 using the calculation

(Stopped HR - HR at 2 minutes)/4

eg..  (124-96)/4 = 7

According to this this evaluation it is excellent.

What are your thoughts on recovery heart rate ?. I feel it is extremely important and not much is posted on the Forums.

[Heybales]

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@Colinm39 wrote:

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@Colinm39 wrote:

@HeybalesMy heart beat is normal.  In a brisk walk. 3.8 mph it sits at around 100 and then up a gradient around 110-115 bpm. When I do some HiiT walking it gets to 130 but no feeling of the heart wanting to burst out of the chest or my ears.

 I passed my annual medical with flying colours and the doctors smile when the HR misses a beat.  They tell me it just misses the 0.2 second timing and nothing to be of concern.

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@HeybalesI also keep an eye on my recovery HR and the difference between the HR when I stopped the activity and 2 minutes later. It is typically 7-9 using the calculation

(Stopped HR - HR at 2 minutes)/4

eg..  (124-96)/4 = 7

According to this this evaluation it is excellent.

What are your thoughts on recovery heart rate ?. I feel it is extremely important and not much is posted on the Forums.

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Very important, as it also tells usually if your body is being trained for carb burning high-aerobic range, or fat burning low-aerobic range.

The former is fine if you just want a big calorie burner, the latter is needed if you are actually intending to do endurance events.

There was only 1 study I recall seeing, not that I searched for it, but happened upon it by distraction, comparing RHR by sprinters compared to long distance (not sure what distance they tested).

Both groups tested for HRmax and VO2max.

Both groups hit some % of one of those, don't recall which, but same effect, high level of effort for long enough for HR to get up and stay up there.

I recalling thinking the % wasn't that high, but then realized it was probably for giving a value the sprinters could stay at long enough for HR to stay there.

Then they stopped and either walked or stood.

Sprinters HR stayed higher longer and they burned more carbs during the effort, the body despite not doing sprint level for short period type run, went straight to high carb-burning ratio. Now, the test wasn't to see if it eventually would lower carb burning at keeping that effort, so unknown.

But the long distance folks had a HR that lowered faster in the 1 and 2 min increments marks.

I think it's not talked about nearly enough, and I'm not sure if any newer HRM's are doing it nicer.

I had an older Timex that logged that with the workout stats, and you could select 1 or 2 min marker.

Current Garmin shows what the value is, but not logged with the workout, so just have to remember to mark it down.

Most others you'd have to note the differences and track the time yourself. So not likely to be done.

I typically can recover 45-55 in the 2 min mark if I truly ended high enough to get that range. During intervals Jogging and Walking, it'll be more like 30 in the 1 minute of walking. I think sprinting / walking it's about the same though higher HR numbers.

I wish I did log that info though, but usually not noting it.

[Colinm39]

@HeybalesThanks for the prompt response. At my age I'm always "listening" to my body and I'm assuming Fitbit are using the RHR for Vo2max which in my case is not accurate. As I have posted elsewhere I had to use the Rockport test to satisfy myself to set the Vo2max on my Polar.

I have been sitting around for long stretches while visiting my daughter in hospital and I was measuring my RHR on the Surge for hour intervals.

Because of the controlled environment in the hospital on the first day my HR averaged 62 bpm and 2.1 calories/minute, on the second day, it was colder and I had to wear a woollen jumper, sitting in the same room and my HR averaged 76 bpm and 3.1 calories/minutes.  My BMR/resting calories are 1.1 calories/minute.

No muscles working, just sitting quietly. Many may not be aware that these probably aren't real calories, just moving the blood through my system faster, hence the higher HR and Fitbit's interpretation.

On studies I have found that you burn real calories trying to keep warm in a very cold environment and don't achieve much when it is warmer so I feel we should make Fitbitters aware.

To put some fun into this ,   I was at the dentist today to replace a  filling that had fallen out and the dental nurse likes to look at my HR when they inject, drill etc.. here are the results.

[Heybales]

Pretty sure fun and dentist shouldn't go together in the same sentence. 😉

Pretty sure my heart gets a 20 min cardio workout for that time, even if rest of the body doesn't.

Well, besides some isometric in the back doing a bridge effect.

True on the cold needing to be really cold for metabolism to feel the need to increase enough to be worth anything.

Also when getting hot without much effort the HR will increase just to aid blood flow cooling.

If working outside it really does that efect.

If getting dehydrated that can increase even more as heart bumps thicker blood around with more beats.

This should be interesting as the first real summer with the HRM devices being used, I think.

They should overestimate calorie burns for everyone doing outdoor hot workouts.

If people stick to their deficit eating goals as they did during the winter, should have reduced loss amounts showing up, perhaps increased claims of difficulty losing now.

[DominicJ]

HIIT doesnt really do it for my heart rate.

The only way mine really jumps is sustained hard activity.

My "best effort" 12.5 kph 1k run barely gets me to 140

My casual 10kph 5k sees me hitting the high 190s no problem, at the end.