MFP/Mapmyfitness/Polar FT7

maoribadger

So I bought an FT7 and decided to wear it to the pool today. Swam 20 lengths in 22.5 minutes so 45 mins/km

Mapmyfitness has me at 391 calories. MFP has me at 308. I weigh about 113 kg so I do burn a fair bit doing any form of exercise. But my FT7 has me at 182 calories, average HR 136 max 152 (felt way faster!). Seems quite a discrepancy.

Anyone shed any light on this or have any thoughts? Thanks

patriciapowerswilliamson

I just read this on Life Hacker, it's worth a read: http://lifehacker.com/the-data-you-can-and-cant-trust-from-your-fitness-tra-1636270779

kshadows

FT7 doesn't accurately track heartrate in the water.

maoribadger

Thankyou, I did wonder why there was such a discrepancy. I've stuck with mapmyfitness's numbers for now purely because I can enter distance and time to get my speed etc rather than a generic MFP number.

Will stick to using the FT7 for cardio at gym and walking then as Ive heard its not accurate for weights either. Mostly just want to see Im getting into a decent heart rate for burning calories (which I need to research to find out how much that is!) when I am working out

Thankyou patriciapower Ive bookmarked that to read when kids are at school tomorrow as I use a fitbit too so will be interested in what it says

gobonas99

MFP and MMR are notorious for overestimating calories.

I have a Polar FT60 that I use for swimming (since Garmin's HRMs don't work in water). I swam 2000 yards (or 1.14 miles or 1830 meters/1.83KM) in 45 minutes yesterday morning and burned 483 calories - avg hr 148, max 162.

If you swam 20 "lengths" in 22.5 min at a 45min/KM pace, and I'm guessing a 25M pool, and you mean actual lengths vs laps, you swam 500M in 22.5 minutes. That is a slow easy swim.

To give you an idea of my pace, my first 500Y set yesterday was 11:04 minutes (so if I divide my total calorie burn by 4, my cals burned in each of my 4 500Y sets would be 121 cals). If I factor in my 11th lap to get to 550Y or 502M, my time was 12:05. I did 1025Y (roughly 937M) in 22:40.

I weigh 90 pounds (about 40KG) less than you, and was moving almost twice as fast, and burned 121 cals .

What I'm trying to get at here is that your HRM is much closer to your actual calorie burn than either the MMR or MFP estimates, so go with what your HRM gives you. :flowerforyou:

gobonas99

FT7 doesn't accurately track heartrate in the water.

Not true. The FT7 is one of the Polar HRMs that DOES track HR in the water.

ETA - You just need to ensure the chest strap is on tight enough to not slip, and that the battery in the transmitter and/or watch is not low (those were the only times I had issues with HR reading with my FT60 - once when the strap was too loose, and once when the transmitter needed a battery change).

kshadows

FT7 doesn't accurately track heartrate in the water.

Not true. The FT7 is one of the Polar HRMs that DOES track HR in the water.

ETA - You just need to ensure the chest strap is on tight enough to not slip, and that the battery in the transmitter and/or watch is not low (those were the only times I had issues with HR reading with my FT60 - once when the strap was too loose, and once when the transmitter needed a battery change).

http://www.polar.com/us-en/support/swimming_with_FT7

It will WORK in the water, but not accurately

gobonas99

FT7 doesn't accurately track heartrate in the water.

Not true. The FT7 is one of the Polar HRMs that DOES track HR in the water.

ETA - You just need to ensure the chest strap is on tight enough to not slip, and that the battery in the transmitter and/or watch is not low (those were the only times I had issues with HR reading with my FT60 - once when the strap was too loose, and once when the transmitter needed a battery change).

http://www.polar.com/us-en/support/swimming_with_FT7

It will WORK in the water, but not accurately

If you read that, it says that you MAY experience issues where your HR is not picked up. That is CLEARLY visible on the watch when it says your HR is 00....and has only happened twice for me in the past two years.

In my experience, it works sufficiently accurately to be a FAR better estimation of calories than the MFP or MMR estimations. My calc'd calorie burns for swimming (along with avg and max HR) are on par with other land-based cardio activities of the same effort level (ie an easy bike ride).

maoribadger

MFP and MMR are notorious for overestimating calories.

I have a Polar FT60 that I use for swimming (since Garmin's HRMs don't work in water). I swam 2000 yards (or 1.14 miles or 1830 meters/1.83KM) in 45 minutes yesterday morning and burned 483 calories - avg hr 148, max 162.

If you swam 20 "lengths" in 22.5 min at a 45min/KM pace, and I'm guessing a 25M pool, and you mean actual lengths vs laps, you swam 500M in 22.5 minutes. That is a slow easy swim.

To give you an idea of my pace, my first 500Y set yesterday was 11:04 minutes (so if I divide my total calorie burn by 4, my cals burned in each of my 4 500Y sets would be 121 cals). If I factor in my 11th lap to get to 550Y or 502M, my time was 12:05. I did 1025Y (roughly 937M) in 22:40.

I weigh 90 pounds (about 40KG) less than you, and was moving almost twice as fast, and burned 121 cals .

What I'm trying to get at here is that your HRM is much closer to your actual calorie burn than either the MMR or MFP estimates, so go with what your HRM gives you. :flowerforyou:

Slow yes.Easy no. I've only been doing this 4 weeks and I weigh nearly 18 stone. So easy for you maybe, made me quite out of breath as I am significantly overweight and unfit. But thankyou for the information, I have taken it on board. TBH I dont eat back my exercise calories anyway, I stick to my daily total of 1510 or usually less and count the exercise as a bonus so the number is arbitary really and even 182 is great as its all making up a deficit

kevswain

Hi Maorlbadger
Well done on the swimming !!!!!!
I am 155kg (and going down)
have a bad AC joint so can only do breast stroke and back stroke

I am now looking for a watch that can do swimming HR would you recommend your watch or a different model based on your experience ?

maoribadger

Ive only ever used mine but it seems pretty good to be fair. Keep up the swimming