Charge HR Calories tracked during workout feel low?

[RyanKovacs]

Hey all!

I recently picked up a Charge HR after I was very intrigued by the daily caloric expenditure based on your heartrate and activities. So far I love the concept, and am more than happy to wear it practically 24/7 to track literally everything.

I just logged my first workout with the Charge HR at lunch at 33 minutes, average BPM 87, and 128 calories burned.

This is a fairely heavy weight and intense workout, although there is reasonable amount of rest between sets. Ranging from 100lb dumbbell chest press, to something as basic as 60lb cable tricep extensions.

I am not entirely sure how the heartrate technology / workout algorythms work, but it did feel as though my heartrate was not right throughout the workout. Especially with my heart pounding after the chest press, and having the fitbit only registering a moderate mid 80 BPM. Frequently throughout the workout my heartrate continued to increase on the device, yet it "felt" consistant throughout the routine.

It kept rising to the peak at one point near the end of 140 BPM (my resting BPM is 65+/-5).

Now, I am personally a 27y old, 6'0", 211lb male. I am quite strong, but i'm also carrying a decent amount of fat at the same time, I would imagine I am ~175lbs+/-5 with 10-12% BF.

I put in my above stats to a generic online calculator for "normal" weightlifting workout, and it came up with 180 calories. Meanwhile another calculator said 141 at moderate, and an article said 130 at virogous!

I am currently on a year long bulk phase and am working on gaining weight, so should I follow the charge's readings and continue my diet based off of my daily expenditure? Track my results and adjust based on monthly weight gain?

[RivalDealer]

You can enter it in manually as an activity, I found when I'm really pushing myself on the rower or with HIIT the Charge HR seems to round off the spikes, try a proper tabata 20sec max effort, 10 seconds rest for 8 rounds and you will probably see the same, you need to do something that will use your whole body as hard as possible, something like burpees should do it.

If you want really accurate HR tracking you need to get a chest band really, the Charge HR is great for all day tracking but falls a bit short when you are putting in loads of effort and getting your heart rate as high as possible.

[DominicJ]

Weight lifting isn't a high calorie burn activity
Its just not.
An Olympic level floor to overhead lift burns a couple of calories.

Hiit isn't great at calorie burn either, however the fitbit is fairly poor at measuring it so probably underestimates.

[Heybales]

HR-based formulas for calorie burn fail on anything that is not what it's intended for - 

steady-state aerobic exercise with HR the same 2-4 min.

Lifting is exactly opposite - anaerobic if done correctly, and HR no where near steady-state.

You normally would get inflated calorie burn because of inflated HR seen - but yours failed to read your HR accurately.

So you can hope that by sheer coincidence the missing high HR causes the calorie burn to be decently accurate - or manually log it.

You were doing what Fitbit calls Weights in the database - and that's based on studies doing exactly what you did.

Still not huge calorie burn as mentioned above, say compared to cardio, but it still counts, and should be counted.

I'd think lifting day would especially be the day you don't want extra undesired deficit, not in a bulk.

[RyanKovacs]

So after reviewing my settings and data after my first full day of use, I noticed something was wrong.

I didn't catch on immediately when I noticed my BMI was 186. I thought, hmm... that's strange. That's like triple the value of somebody clinically obese. (given BMI for a bodybuilder is garbage, considering its a calculation based on specifically weight/height and nothing to do with composition). I shrugged off the value since BMI doesnt matter to me.

this morning it clicked in my head after I noticed I only burned 2200 calories yesterday with 7000 steps + workout for a 210lb man. oh **ahem**. I know my weight is correct, but let's check my height. Sure enough, I put in 72cm thinking the value was inches.

So the device was monitoring me as if I were a 210lb 2 foot man lol.

Updated my info, my daily expenditure shot up to ~3000 calories, my BMI normalized, and my 30 min workout today yielded 175 calories. Everything appears to be correct and surprisingly accurate!

[Heybales]

Being that short - you should have seen if your deadlift 1RM could be higher.

[Julia_G]

@RyanKovacs , I had a similar issue...I have a One and a Charge HR, and my Charge HR was really stingy compared to the One on how many calories I managed to burn each day (I have them set to different accounts so I can wear both). When I double checked I found the Charge HR thought I was a 122 lb woman, and the One thought I was a 122 kg woman! Too bad the CHR was correct, because I really preferred the calorie burn / allowance that the One gave me. 😉. Moral of the story: check your units!