Fitbit Versa Cardio Fitness Score Accuracy

[SawyerFTW259]

I have been using my fitbit versa since July and it seems to me that my cardio fitness score is way off.  My score is 39-43 which is poor to fair for men who are 19 years old (which I am).  I am a 6 foot 2 inch male who weighs 235 pounds. I exercise 3 to 5 times a week for a half hour on average and I take 7,500 steps a day on average.  I also have a resting heart rate of 61 BPM.  Given that I do not run outside (I use an elliptical), my cardio fitness score still seems very inaccurate, since I run 3 miles when I am on my elliptical, and I bike 3-7 miles on trails.  If anyone has any suggestions on how I get can my cardio fitness score up to average or even very good, it would be greatly appreciated.

[JohnnyRow · Accepted solution]

Read How does Fitbit measure my cardio fitness score?

and

How do I get a more precise estimate of my score?

As they tell, it really take some outdoor running speed-hear rate correlation to get an accurate reading.  Other than that, it's just a guess based on your other stats.

[SawyerFTW259]

Would going on long walks (30 minutes) using my GPS give me the same results?

[JohnnyRow]

For one thing, you would have to tell fitbit you will be running, not walking.  Other than that, not sure. I expect would be more accurate walking faster but shorter time, at least 10 minutes.

[Emma_Muhleman]

My understanding based on the definition of VO2 Max and how it goes into your FitBit score, long walks with GPS would not be of much help. You really want to go for a 10 minute run on a flat-terrain with GPS enabled. During this 10 minutes, if you can you want to add some high intensity running, as your Vo2 Max can then be calculated more accurately. Vo2 max is widely used in academic studies to evaluate different workout regimes and the benefits of one versus another: checkout a thing called "The Wingate Test." I'm at Harvard thus I have access directly to these studies, but for those interested in Cardio Fitness Score I highly recommend Googling "the Wingate Test HIIT 30 seconds." I'll give a very rough summary here: Researchers analyzed the efficacy of HIIT based on achieving 90% Vo2 Max relative to much longer periods of moderate-intensity exercise and the results were quite encouraging (for those of us who'd prefer to work ourselves to death for 30 seconds, 4x in a row rather then spend 50 minutes with our heart rates slightly elevated). They gathered somewhere around 100 healthy college students for a control group, another 100 healthy college students for a "moderate-intensity" group, and another 100 healthy college students for the Vo2 Max HIIT evaluation. One group did no exercise beyond their regular daily activities. The "moderate-intensity" group did 30 min moderate-intensity exercise, 3x per week, and the HIIT group literally did 2 total minutes of exercise 3x per week (30 seconds at Vo2 Max, 4 minute break, repeat 4 times and you're done --> actual time exercising is 2 minutes here). The results were astounding - the HIIT group's Vo2 max and fitness levels, endurance, etc had improved drastically over the observation period of ONLY ONE MONTH, while the "moderate-intensity" group only slightly improved relative to the sedentary/non-exercising group. 

[Bleeh]

Just wondering how accurate is the VO2 Max estimate on the Versa.

It pegs me at 57-61, which kind of surprizes me, pleasantly, of course. To put it in perspective, I am not a dedicated exerciser (haven't been to a gym in probably 20 years), although I have a mat and do one or so daily sets of: 10 pull ups, 20-25 chaturanga push ups, 70-100 sets of side crunches, a set of 17-20 arm curls (20lbs) and about 30-40 leg squats, for a total of maybe 20-30 minutes. I also walk a few times a week with my dog, usually at a brisk pace (just finished a hill walk and Versa counted 1m peak, 44m cardio and 40m fat burn so far today (early Saturday afternoon). My "resting" heart rate according to Versa is 53-56, which is consistent with the "average" heart rate my old Gear s3 and before that Gear S2 have registered over the last three years or so. I am also vegan.

I've never thought of myself as being in great shape, since I don't run, or do anything too strenuous. I think I am relatively fit for my age and maintain about 151 lbs, at 6'1". But FitBit says I am "excellent," at least compared to my age group.

How trustworthy is FitBit's assessment and has anyone compared it to a lab test? Just want to know if I should keep my vegan smugness in check (even though I don't eat meat for moral, and not for health, reasons). 🙂

[LZeeW]

@Bleeh   I peeked at your profile and I see that you are very new to Fitbit.  I am not sure you have enough data to be confident in your Cardio Fitness Score.  If you really want to refine your Cardio Fitness Score, then do GPS connected runs on a relatively flat terrain.  And wait a little more time and collect more data.

You do not give your age, so how does Fitbit compare your V02max to other people your age?  I don't know what 57-61 means.  I think it is fair to say that someone's V02max predicts their ability to do "endurance" exercise. 

In my younger years, I was a long distance runner.  My current Cardio Fitness Score, BTW, is excellent for my age and I think reflects the physiology I was born with and optimized. But I sure can't run like that any more.

[Bleeh]

Haha. Yes, I am a baby in FitBit years, but have passed the mid-50s in human years.

57-61 is at the high end of "excellent" in FitBit's Cardio Fitness Score, but now I am guessing that we are all well "above average" when we start in the FB's world.... 🙂

I like hills, but will try and do a flat run with this thing and see how it goes, thanks.

But, I am still curious, if someone like @Emma_Muhleman above, has insights on how FitBit's Cardio Fitness Score compares to actual VO2 Max scores from lab tests.

[DQGab]

Question for you guys. I am concerned about the Cardio Fitness Score. I haven't ran in 2 yrs and my daughter does 1/2 marathons. When I just found this score, I compared with her and ours was the same, 38. I asked if she wanted to do a 'race' to see who could increase theirs the most over a time period. She said that hers has been the same since she was 30 lbs lighter and running 7 miles/day in highschool. So this makes absolutely no sense at all. When she was lighter and ran more on daily basis her score was the same? So we are concerned about the accuracy.

[Karategirl83]

I am an Exercise Scientist and I manually calculated my own VO2 using the Queens College Step Test, a test used in occupational fitness testing and compared my results with that of the fitbit and they were the pretty much spot on. So congrats on your results.