Blaze vs Chest Strap (polar H7): A review

[AdamMSC]

PLEASE READ THE REVIEW AT THE BOTTOM: I got different results my second time around, but I am leaving this up here as a source of information for others.

Testing

I tested the Blaze vs the H7 today at the gym. I used Endomondo for the H7 and the Fitbit app (of course) for the Blaze. I started the exercises simultaneously and used aerobic and anaerobic movements. If you have any questions, please feel free to ask. If you would like me to test other workouts, please feel free to ask. I will be happy to help you make an informed buying or returning decision. What did I do? Tread mill, jump rope (moderate and intense; regular skipping and double unders at roughly 30 second intervals), back rows  (machine and free weights), lateral raises (dumbbells), push ups. I consistently checked the Blaze against the Endomondo app with H7 monitoring. 

Review/Thoughts

The Blaze does an exceptional job tracking heart rate for exercises under ~155 beats (it does *rarely* have a spiked drop here and there, but generally it is right on). Once the heart rate goes above that, it is hard to know if it is accurate (which it sometimes was) or is hardly accurate (which it sometimes was). The conditions that gave me different results were the same: jumping rope. With regard to the weights, I did not have trouble with the device. It was within  approx. 5 beats of the chest strap. I believe the discrepancy while skipping rope comes from the Blaze's inability to quickly track a a pulse once it reaches the anaerobic zone. The sensor on the Blaze records your pulse every second and scans it many more times than that per second; however, it doesn't do a great job once your heart react reaches the 150s and up. Interestingly enough, Fitbit describes the peak zone at about 152... and that is right about where the device starts to lose credibility. A few times-I stress a few- it did keep up with the chest strap and go into the 160s, but there were many times when my heart rate was at 180+ and the Blaze was nowhere to be found (it was in the 150s).

Conclusion
Just like you'd expect, the Blaze doesn't do great with extremely intense exercises. However, if you are doing moderately intense to intense workouts, you can count on it to be pretty spot on, and I mean very, very close!!!! Below are the graphs of the workout. With that said, your calorie count is definitely going to be thrown off because the Blaze is less likely to put you in the anaerobic zone. Blaze had me at 473 while the H7 on Endomondo had me at 596.The top is the chest strap (with endomondo), and the bottom is the Blaze.

[AdamMSC]

I was referring to the cardio portion of the graph. That is what I said was dead on; it was and has been when I have done cardio on the treadmill. And yes, I have found that is has been inaccurate while doing certain exercises since making previous posts; so I do agree with you there. That was shown by the first test I did. The second one was much better, but since then I have found it to be on and off while doing HIIT. Once again, though, I have not had a problem with it while doing cardio on the treadmill, and that is what I was referring to as being dead on.

[AdamMSC]

As for practicality of your heart rate throughout the day, I use it while teaching. I am a Phys. Ed teacher and found that I went home exhausted on many days. The ability to track heart rate and steps throughout the day definitely helps me take control of my breathing and my decisions to take it easy with some classes. I am very interactive with my classes, but it was taking a toll on me. I was hitting  roughly 25,000 steps a day my first couple of weeks wearing this (on top of going to the gym in the evenings), and I have used the data to drastically cut back on my activity throughout the day. I use the heart rate data while I teach too. It's very useful for me!

[cenetti]

Tracking HR through out the day is crucial for accurate(ish) calorie calculation. Not every step is same. 

I can walk from my living room to the kitchen and back and put 200 steps with my HR is around 60. Now I can go out to take the mail and walk 200 steps with my HR is around 90. Calorie burn for 200 steps will vary greatly

Also after a workout, metabolism will rev up. Calorie burn based on HR will be greatly different ( up to 3-5 cals a minute) for several hours. After waking up sitting around HR will read 55ish. However after a hard workout, later sitting around HR will be 65-70. 

[bbarrera]

@AdamMSC

Would be nice for you to update the review in your initial post with the findings you reported here:

https://community.fitbit.com/t5/Blaze/HR-monitor-inconsistent/m-p/1281603

[AdamMSC]

After having the device for over a month and running a lot of tests, I have once again changed my position on the hr monitor. It is inconsistent -- point blank. Sometimes it seems to do a great job and other times it is  off. The device isn't terrible at tracking cardio; it does a good job at that. However, after testing it more and more with high intensity work outs (jumping rope, weights), it is inconsistent. Sometimes it is close, and other times it is way off. The problem is that I can't seem to figure out why... I thought that moving it up on the arm would make a difference, and it did here and there. However, there have been times where the Blaze doesn't get close to the actual hr given by my chest strap, and I don't know where the discrepancy lies. So... you need a chest strap if you want something accurate for any sort of activity that is taking place in the gym that isn't slow and cardio-based. 

[FelixFive]

@cenetti "Tracking HR through out the day is crucial for accurate(ish) calorie calculation. Not every step is same. "

HR is indeed important to gain a more accurate view of calorie expenditure and subsequently calculated calorie intake recommendation.

Unfortunately the Blaze's unpredictability in step count accuracy, active minutes logging, and heart rate monitoring (all documented in other threads) create enough imprecise variability as to negate much of the caloric validity. It's not always bad data, but not knowing *when* it's bad data or *which variable* is bad data (without constant monitoring) makes me distrust the overall attempt at caloric monitoring.

But if you think it works for you that may be all that matters.

[irish_yooper]

I agree....I am a Fitbit user for 3+ yrs but never was an athlete.  I am serious now with osteoarthritis of doing warm pool therapy and workouts, shape up and lose weight.  I have been using the fitbit HR Charge 2 for a few months....resting heart rate of 68-70.  Put my old Polar F4 chest monitor and watch on...HR is 48!!!???????    I want to track my heart rate in the pool; my fitbit model can't be used in the pool.  I am quite shocked on the differences in heart rate.  As I get more competitive, I probably will got with Polar or another competitor that can be worn in all weather and pool conditions.

[Slavs06]

Which chest strap is the best value