heart rate monitors fitness trackers?

Caporegime
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One of the comments in reviews (cnet IIRC) about the Garmin HR 'elevate' sensor builtin is that (a) it lags by about 6 seconds and (b) although in normal running use it's reasonably accurate, compared to a Polar chest strap during interval training it becomes inaccurate the longer it's used (and that carries on into the cold down).

I'm interested, and will probably get, the Garmin Forerunner 235 GPS. Although it suffers from the above, I have a Polar chest strap and Polar watch for any intervals on a treadmill. I'm more interested in a general GPS/HR watch for that.

What I would say is that check carefully functionality doesn't require additional accessories. The VO2, and some of the cadence etc of the Garmin watches require their chest band or swimming chest band in order to provide it. Additional cost to what is an advertised selling point!!


The Vo2max calculators on garmin watches need any HR monitor, doesn't matter what provides it. Obviously the more accurate the HR monitor the better, but the VO2Max estimate is not accurate anyway so not a deal breaker.
 
Soldato
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What is it with all these watches for monitoring heart rate, step count etc.
Why not just measure pulse rate at the wrist for 15 sec and then times by 4.
I think all these gadgets are a waste of time and money.

I thought a lot of the wrist based ones do a lot of averaging to make up for detection errors, so may just be implementing ~the algorithm you proposed.
With the chest straps (PolBT2), as discussed in running thread you can find your applications will smooth the data too, so you do not get to see
what happens if you inject say 30s of faster pace into a run - have a look at the links on how polar 'adjusts' your data.
 
Soldato
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from https://www.livescience.com/56459-fitness-tracker-heart-rate-monitors-accuracy.html

Each of the 50 healthy adults wore two trackers at a time (one on each wrist) while walking on a treadmill at different speeds, from 2 mph up to 6 mph (3.2 to 9.7 km/h). The participants also wore a device from fitness tracker company Polar, called the H7 chest strap monitor, as well as electrodes used for a standard electrocardiogram (EKG) test, which also monitors the heart's electrical activity.

The measurements from the Polar chest strap and EKG were nearly identical, but the wrist-worn heart-rate monitors were not as accurate.

Of the four wrist-worn monitors, the Apple Watch and the Mio Fuse did the best. Most (95%) of their measurements fell within a range of 29 beats per minute (BPM) under the measurements from the EKG to 27 BPM above it. In contrast, the Fitbit Charge HR had measurements that ranged from 39 BPM under to 34 BPM above the measurements from the EKG, and the Basis Peak had measurements ranging from 33 BPM under to 39 BPM above the measurements from the EKG.

The Charge tended to underestimate heart rate, while the Peak tended to overestimate heart rate, the researchers noted. In general, the wrist-worn monitors were most accurate when the person was at rest, and their accuracy diminished as the wearer's activity level increased, the researchers said.

free page form paper
36509066394_dd7c19cd8c_o_d.jpg
 
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Soldato
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looks like the new Optical polar might be interesting , if you are in the market;
I would like something that would work in a pool where a full metal jacket chest HRM, is not very practical,
and having something on upper arm could be good, even if some accuracy is lost.
maybe need to wait for updates though.
Received my OH1 today, some comparisons with Scosche show very similar HR results, however I am very disappointed that they did not put more effort into the strap. It’s the standard cheap elastic and isn’t wide enough to spread the load. When I got to the end of my circuits training I realised it had managed to flip itself over during the class! Presumably swimming will have similar results when pushing off.
It’s a shame that a technologically advanced piece of kit can be let down by practicalities, hopefully they come up with a premium alternative solution or I’ll be attempting a DIY.
 
Caporegime
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Nice find. It also collaborates what I said before (not sure in this thread or elsewhere). The optical wrist based HRM are pretty good for sitting at your desk, sleeping, going for a walk. When actually exercising, especially if you some interval work they are pretty bad. The chest straps are really good, especially when exercising but obviosuly aren't fun to sleep in.
 
Caporegime
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looks like the new Optical polar might be interesting , if you are in the market;
I would like something that would work in a pool where a full metal jacket chest HRM, is not very practical,
and having something on upper arm could be good, even if some accuracy is lost.
maybe need to wait for updates though.


I have the Scorche, it is widely regarded as the best Optical HRM on the market but honestly it just isn't very good. So if the Polar one is similar I don;t see it being very good.
 
Soldato
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I have the Scorche, it is widely regarded as the best Optical HRM on the market but honestly it just isn't very good
I did subsequently look at Rainmakers review ,for him, apart from 20s exercise bursts it was close to a strap, so your experience is disappointing.

A radio programme this morning, discussed impact of inadequate sleep on heart attacks (mortality go's up 24% when clocks go forward) so would be interesting to try and monitor sleep quality with an hrm, if it is an indicator.
 
Associate
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Have used the Garmin 735xt for over a year as an everyday watch. I do triathlons too which is my reason for getting it. Battery life is brilliant (about 2 weeks in watch mode). The 935xt which replaced it is supposed to be even better in this regard.
 
Soldato
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I did subsequently look at Rainmakers review ,for him, apart from 20s exercise bursts it was close to a strap, so your experience is disappointing.

A radio programme this morning, discussed impact of inadequate sleep on heart attacks (mortality go's up 24% when clocks go forward) so would be interesting to try and monitor sleep quality with an hrm, if it is an indicator.

I've got a Scosche - it replaced my last Garmin chest strap. Very happy with it, just need to remember to it charge every few weeks. Very comfortable to wear when running or cycling (even with arm warmers when cycling which have a gripper at the top of the arm).

Haven't gone to DCR lengths to compare accuracy but I think it tracks efforts well. This is from a turbo trainer session on my bike with multiple 1m intervals

655ec5fb01a12f44b44b22065c73a9e2.png

https://gyazo.com/655ec5fb01a12f44b44b22065c73a9e2
 
Caporegime
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I did subsequently look at Rainmakers review ,for him, apart from 20s exercise bursts it was close to a strap, so your experience is disappointing.

A radio programme this morning, discussed impact of inadequate sleep on heart attacks (mortality go's up 24% when clocks go forward) so would be interesting to try and monitor sleep quality with an hrm, if it is an indicator.



The problem with the scorche and most optical HRM is it locks on to cadence rather than your HR. When you are at easy pace it is obvious but in a race or workout it is not obvious. Pretty much every run for the first 10-20minutes it will read so string like 180, when I know my HR is 142-150 at easy pace depending on temperature/recovery. You can try and reset it with a power cyle but it takes 3-4 before it finally decided you heart and not you feet pounding the pavement is what you want measured. And after the initial problem , you will still get blips where it gets your cadence.Same deal, you do an easy pace and glance at your watch and see something like 167 which seems high but maybe you pushed too hard up a hill. Then you see that ever second it slowly lowers down to 151 despite keeping constant pace. It locks on to your cadence, and then because it does so much averaging it takes ages to get back to normal. This averaging then makes you realize that it is useless for intervals You also tend to get more problems as you with static readings.

Within training you can come with this,although it makes it hard to do late data. The real problem is in a race. For example in a marathon i want my HR under 175. But if i see 180 I don't know if I am running to hard and should back off 8-10sec a mile, or it is just reading cadence lock. Since I can't trust it it tends to make it harder to train and race by HR, which kind of makes it pointless.

Then there is The battery issue. For training The 8hrs is ok, but you will need to charge every couple of days and since you don't get much warning it is better to charge it every night. For more casual runners this is problem less of a problem and a weekly charge will suffice! The real problems comes in an ultra, after 6-8hrs it will cut out leaving you with no feed back for The next 6-30 hours. A chest strap will last a year in comparison.


The EGG chest straps have their own problems but are well ahead of the optical s
hRM. It is more comfortable but after after few hours does cause an ache. A chest strap can run but I have had it on for 6hrs in jungle like conditions without issue.
 
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Soldato
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most optical HRM is it locks on to cadence rather than your HR
not sure I understand , are you saying optical reader is disturbed by jolts from step, or the watch uses cadence/accelerometer to enhance HR algorithm -
can you disable cadence aspect (... or have two watches)

Another vector Is the Heart rate variability, this is an interesting primer
it would appear that natural variability of heart rate is expected, and that higher variability is good in athletes and indicates good physiological state, the example shows, within a minute the instantaneous rate has varied from 55->72 beats/min.
Some athletes appear to monitor it, and determine whether diet/sleep/stress can be modulated to improve(increase) it - maybe it is snake oil
(inevitably) It appears with chest straps these can give accurate indication of variability, when they compared devices.

Given the variability, displaying instantaneous, would be confusing for the user, so I guess it has to establish variability (does it scale with effort) so that you can establish statistically what the average beats are.
The article does not seem to reveal what kind of minimum sample is needed to confidentaly do that. (is it 20s, a minute ?) plus if you are changing your effort level - the algorithm is pretty complex.

For pro cycling (have any used optical - that would be a marketting coup), wonder if they have enhanced algorithms on their HRM's, hardwired with their variability profile,
to accurately avoid the 'red' zone, even for short periods; power meter output may help in that arbitration though, no good equiavlent for running ?

(I had mentioned getting raw polar strap data into excel in an earlier running post - but I now think I need to beg/borrow a good piece of VBA for processing it)
 
Caporegime
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Optical HRMs pick up the jolts form running and also the arm swing, so even doing an upper body workout or game of tennis etc. they aren't accurate. the rpoblem running is you get a very repetitive 170-180bpm tempo from each foot step. Optical HRm are extremely prone to picing up that signal rather than blood flow.
 
Soldato
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Optical HRMs pick up the jolts form running and also the arm swing, so even doing an upper body workout or game of tennis etc. they aren't accurate. the rpoblem running is you get a very repetitive 170-180bpm tempo from each foot step. Optical HRm are extremely prone to picing up that signal rather than blood flow.

Not had that problem to be honest - I have had it lock onto something for a 180bpm period - but for the walking and running on the treadmill the Forerunner 235 seems ok although as always given a pinch of salt. I have a polar chest strap I'll try next time on the 'mill and report back with differences.

Actually like the 235, it's got a sort of charm with the large digital clock face, etc. It's shown I already walk a mile each way from the train station in london to work, the treadmill then doubles that and it will get better as I get fitter.

I did this to test the GPS performance, 9.5 hours of continuous GPS and it still had some battery left. Skippers don't like you doing this but this doesn't show anything more than people know already (no secret wrecks here):

Screen%2BShot%2B2017-09-30%2Bat%2B18.32.25.png
 
Soldato
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Spent the week in Manhattan.. one issue I did find with the HR monitor and 24/7 wearing (except shower and cleaning) is that it will cause your skin under the sensor to have problems if it's subject to sweat.

The GPS had problems locking on in built up Manhattan.. I finally tried it part way around the bike ride we did:
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Soldato
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I'm very interested in picking up a cheap mi band 2. any views guys? Don't need anything too fancy, just something to get a bit of data into health apps.
 
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