Have the Strava alg...
 

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[Closed] Have the Strava algorithms changed recently?

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I know Strava and Garmin times can differ due to the auto stop speed settings and GPS vs speed sensor but I've noticed the difference getting bigger in the last few weeks. It used to be 0.1-0.2mph but several rides recently have been 0.3-0.4. I also noticed a live strava segment being a PB only for it to be 7 seconds slower over 1 minute when uploaded to Strava.


 
Posted : 17/04/2017 6:23 pm
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It's incredibly inaccurate, my mate is faster than me, beat me by a good 2 or 3 seconds on a 70 sec descent t'other day, according to Strava I was 22 secs faster than him. Both on Garmin vivoactives.


 
Posted : 17/04/2017 6:27 pm
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In that case it's the vivoactives which are inaccurate. I have one too. They only sample the GPS every 15 seconds compared to every 1-5 seconds on a dedicated GPS device so there will always be more error, which gets translated when you upload it to Strava. As a result, I don't use mine for biking, just running or walking where the speeds arent as high.


 
Posted : 18/04/2017 6:55 am
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While we're on the subject of Garmin vs Strava - what's with the calories calculations? I feel really good about myself after my garmin tells me how much cake I can eat now (calories burnt) - but Strava is about 1/3-1/2 the amount.


 
Posted : 18/04/2017 7:59 am
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You can switch vivoactive to do a once per second sample. By default they use smart sampling which just logs significant changes in speed or direction.


 
Posted : 18/04/2017 8:01 am
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^^^^^^^^ This is the first thing anyone who is serious about their data should do on a new Training device. So many come set to smart by default which is ok for recreational use.


 
Posted : 18/04/2017 8:06 am
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what's with the calories calculations?
They are made up numbers, so can be safely ignored.


 
Posted : 18/04/2017 8:07 am
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Yes that is a good point you can change the sample interval. I just save the battery on mine and use my 810 for longer days.


 
Posted : 18/04/2017 8:12 am
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I must admit I've seen very little difference on battery life after switching sample interval to 1 second. Yes it's a little short but maybe half a day's worth 5.5 vs 6 on a Vivoactive HR


 
Posted : 18/04/2017 8:16 am
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Oh OK thanks Micky. I'll give it a try. Just assumed.


 
Posted : 18/04/2017 8:19 am
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Hmmm...

For some reason when I go into sensor menu to change sampling, GPS is not there?...

Edit - Ah, found it.


 
Posted : 18/04/2017 8:39 am

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