How much should I trust my HR monitor?

knt217

I wear a Polar FT4 everytime I work out. When I log my calories burned, I'll put the exercise I did into MFP, but I'll adjust the time to be inaccurate in order to get the calories accurate for what my Polar says I burned. I'm curious though how much I should trust it? I'm not supposed to trust MFP...I'm not supposed to trust gym machines...is it wise to trust my Polar? I understand it's more accurately fixed to my with my stats put in, and it consistently measuring my heart rate- just wondering what other's thoughts are.

TimothyFish

I would trust it to tell you your heart rate. I wouldn't trust it to tell you how many calories that translates into.

jkwolly

Your HRM would be more accurate, but only for steady state cardio!

Take all other burns with a grain of salt.

Sued0nim

You don't need to adjust the time, you can double click on the calories and adjust them directly

It depends what you're doing

For steady state cardio I take 100%

But I do mixed programmes with calisthenics and weights so tend to knock it down

You can really only tell over time by judging it against your weight loss (say over 6-8 weeks) I like trendweight for this (others use happyscale or libra apps)

knt217

I've been doing a mix of workouts too. Boot Camp, WERQ, Zumba, and running on a treadmill. I've been logging the calories it tells me, but not eating all the calories back. Really just trying to stay at 1600 cals net. I've had a few days where I was just hungry and went over, but have also done more cardio those days...so I guess we'll just wait and see. Thanks.

ETA- I may be able to edit calories burned with exercises on my computer, but my mobile doesn't allow me to.

Ideabaker

"Steady State Cardio"... does that mean that interval cardio calories (i.e. wind sprints) burned would not be calculated accurately on the Polar Fit HRM? If not, then would the readings be too low, or too high?

Deena_Bean

I also have the FT4. I believe it for the most part, but I only record 80% of what it says for cardio. I lift 3 days a week with minimal cardio on those days. Today was a lift day - HRM said about 350 calories for 55 minutes. I recorded 175 of that (so 50% instead of 80%). I have no idea if that's the best idea, but I feel ok with it. I did read an article about how much you burn lifting - and it's extremely difficult to calculate because there are so many variables. The generalization is that a 125lb person burns roughly 90 cal/30 min of lifting, 155lb person burns 112cal/30min and 185lb person burns 133cal/30 min. Obviously this is completely a loose definition because it can't possibly take into account what exactly is in that person's weight training line-up. I kind of use that as a marker though. So I worked out for about 55 minutes which would (by their calculations) put me somewhere around 240 calories burned (I'm about 175lbs). My HRM said 350. I chose 175 - still well below both the predicted burn and the HRM burn. So I can eat back those calories feeling pretty ok that I'm not blowing it. Maybe I'm wrong, maybe I'm not - but it's been working ok for me so I'm gonna roll with it

Asher_Ethan

If you eat back all your exercise calories from your HR monitor and still loose weight, then I would trust it.

I find that if I eat back only half of what my HR monitor says I loose weight.

jmasci20

I like the 80% rule for the calorie burn estimated by my HRM which uses a chest strap. I've been at this for 8 weeks and the weight is coming off according to schedule.