Heart rate zones

[Ploddingon]

Today I wore my fit bit for the first time in 2 years for my run. I ran for 30 minutes and did find it hard, as it's still too warm for my liking, even in early morning. But I was very surprised when I checked the data, that only 20% of the run was cardio and the rest was in the peak zone. Is that ok? Is it too much. Any thoughts appreciated.

[Rignold]

Data from a Fitbit. Doesn't surprise me at all.

[MarkyD Graduate]

Well, these watches and fitness trackers are doing a very difficult thing in measuring your heart-rate. Whilst they are shining light & infra-red into a random part of the outside (probably bony) part of your wrist, then measuring the reflected signal, you are also doing your best to shake the device off by your swinging arm motion. That's a very hard technical challenge.

At the same time, dividing your heart-rate up into 5 zones is quite arbitrary, too. The fitbit can only guess your peak heart-rate from your gender and age, and there is quite some variability in your actual peak heart-rate. I'd guess that you have not had your peak heart-rate measured, nor entered it into the settings of your watch.

So, the data from your fitbit is measured approximately (to the best that the technology can do) and then compared to a 5-zone model where the zones are guessed by your fitbit from a simplified model.

So, no, I'm not surprised on the cardio/peak readings. If you want to run cardio or fat-burn, then slow down and run longer. If you are training to run faster with intervals, then run faster and train in the Peak zone. But don't get too distracted by the HR zones from your fitbit.

[Ploddingon Graduate in reply to MarkyD]

Thanks. I was just surprised, as i thought it was a tough run but definitely not at a pace where I would do intervals.

[Realfoodieclub Graduate]

I watch my heart rate when I run because it runs a bit high, (naturally, all checked out) In all fairness though I really don't need my garmin to tell me when I'm running in a zone that is too high, every fibre in my body knows it. It is a different feeling running in the top zones and you are aware of it. If you only noticed when you looked at your data I would suggest it is either not that accurate or your max level is a bit higher than the norm. My calculations for max heart rate are at 188 bpm which is a lot higher than the average so I can run with a higher bpm and all my zones are adjusted accordingly.

If you looked at your data because you felt the run was too hard and you felt like it was too much that is a different matter and I would slow down a little and see if that helps.

[Ploddingon Graduate in reply to Realfoodieclub]

I think it had a lot to do with how hot I was. I didn't feel it was too hard but certainly hard enough.