Elevated heartrate while flying

[mecrtp]

I was wondering if anyone else has seen what I just did...  I happened to be looking at my HR for the last week or so and noticed something interesting.  My HR was consistently elevated while sitting on a plane to/from Europe.  My normal sitting around HR is generally in the low 60s.  On the plane it was in the 80s - and never below.  I am guessing that this is due to a physiological effect... less O2?   But one could also think that the tracker measures differently somehow?  Or that I get nervous flying (if I do, I am not aware of it).

[BobWang]

Cabins are pressurized to ~7,000 ft elevation,

so pO2 is lower than at sea-level.

Your body compensates for the relative hypoxia by increasing heart-rate.

[mecrtp]

That is what I figured but IDK how much to expect to see as an impact.  AND it was pretty cool to see it so clearly on the HR history.

[BobWang]

If the O2 sat monitor ever gets activated, and available to end-users,

you'll also see a drop in O2 sat on planes.

Unless, somebody lives at a higher altitude than 7,000 ft 😉

[NellyG]

That is really interesting!

[BobWang]

For those interested in a short article on oxygen and altitude, just Google:

"Why does my oxygen saturation drop when I get up and move around?"

I would post a link, but I don't know if that is allowed 🙂

[Venkats]

I don't think it has anything to do with the tracker. Assuming you wore the tracker as it is supposed to be, peripheral O2 saturation potentially induced an elevated heart rate and you will need to consult with your physician. Have you ever experienced difficulty exercising in a treadmill at 10 mets or higher? 

[mecrtp]

I am pretty convinced that this is an artifact of flying as others have opined as well.  I found it interesting to see so clearly on the data.  @Venkats thanks for the concern but this is not a personal health issue unless it is an allergy to business travel - which is very possible 🙂  I swim and cycle and have no issues at all with strenuous exercise.

[BobWang]

The U.S. Olympic Training Center is located in Colorado Springs at 6,000 ft elevation.

IOW, "natural" blood doping 😉

But seriously, you can get pulse oximeters for under $20 on Amazon, and watch your own O2 sats fall and HR increase, as your flight climbs to cruising altitude.

The reason that cabin pressure is not set lower is that 7,000 ft is approximately where "altitude sickness" first starts to manifest itself.

[Venkats]

I may be wrong; honestly I never watched it for myself during flight vs pre-flight nor do I have a high altitude training experience. I think once acclimatized, the heart rate should come back to normalcy. A quick google search confirms this thought.

[BobWang]

Yes, people who live at high altitude gradually acclimatize, e.g. increased hemoglobin.

However, physiologic adaption has its limits, that's why highest city is ~17,000 ft.

Living on the moon would definitely require an artificial habitat.

[Lightstorm]

I just had an experience with hypoxia that I’d like to get folks feedback about. I, too, casually noticed that my heart rate was 180 for ten min on a recent cross-country flight. My rhr before this trip started was 53. I was sleeping so I chalked it up to anxiety dreams and/or the turbulence I was aware of. Does this mean I’m at risk on future flights? Feeling a bit scared. Can I do something preventative next flight?

[alexthecat]

@Lightstorm that seems like something that you would want to discuss with your personal healthcare provider. Please do keep in mind that your Fitbit is not a medical device. 

Regarding some earlier posts in this discussion, I live at about 7200 feet elevation. My heartrate doesn't change much when I'm in flight. It certainly does if I disembark at sea level though!