So new to this Strava lark and quite like it. Went round Swinley the other day and measured my time with it.

What I don’t understand (not that it matters) is the power output.

On some bits it’s saying 22W and others it’s saying 230W

I don’t get it ❓

Is there a good average for a Trail type ride?

Unless you are using a power meter I’d ignore the strava generated powers as they are usually way off the mark.

It’s an approximate calculation of the watts you are using.

22W would suggest you are on a downhill section.

230W that you were putting in some effort of the flat or uphill.

Strava power calculations seem to be a work of fiction.

Rode a segment the other week – those of us who use Strava were all within a few seconds of each other but the highest power was twice that of the lowest. We’re all similar weights which is the only other variable that Strava has

yeah, strava clocked my wife as running, yes running a 3 min 40 mile… that’s faster than the world record for a man, on a track.

i’m sure it’s power figures are spot on.

That’s due to your inaccurate phone GPS receiver though most likely.

it’s also got a view of your accelerations so innacurate data could give it the infrance thwt you’re accelerating hard. The weight of tge bike has a disproportioate effect on strava too, 30lb mtb records almost double the power of the 15lb road bike, presumably because it infers the mtb is off road and has draggy tyres.

maybe the road ones are better as strava must have mountains of data from power meters hrms cadence speed etc to build better algorithms from.

The weight of tge bike has a disproportioate effect on strava too, 30lb mtb records almost double the power of the 15lb road bike, presumably because it infers the mtb is off road and has draggy tyres.

I’m no physicist, but surely to move 30lbs up a hill requires twice the power that 15lbs does?

It’s a “Best Guess” feature, probably using AVG Speed Vs whatever incline the Open terrain mapping tells it you were going up/down (VAM) and factoring based on whatever you entered for your body weight…

I tend to ignore it, if you go and look at any given segment the estimated power numbers for different riders who are separated by just fractions of a second (even riders who were physically a couple of feet apart in real life) vary wildly the field is only really there so that people with proper power meters can upload that data and have something additional to analyse or compare…

TBH I’m not sure why they display a guestimate value, rather than just leave it blank like the ‘HR’ field if you don’t have any proper data to populate it with.

but hey-ho, only of any use if you have gathered valid power data, otherwise pointless so don’t worry about it…

That’s due to your inaccurate phone GPS receiver though most likely.

correct.

it then applies a slightly inaccurate algorithm that makes no allowances for weather conditions / road surfaces etc. to calculate power output.

assume it’s not correct.

I’m no physicist, but surely to move 30lbs up a hill requires twice the power that 15lbs does?

only if it has a weightless rider

Not bothered by it, as it’s useless to me, just interested as to Watt it means 8)

Get your Coat!

e, just interested as to Watt it means

Joule be wanting applause for that one in a second… 😉

I wish I knew a way to pun something about power… btu I don’t.

I read an article about the power calculation on strava and as already said, its basically a calculation based on speed, distance incline and probably rider weight ( if entered )

I took the general jist of the article to say that whilst the strava calculation cant be considered accurate at an immedaite instance, that over the course of a complete ride, the average power value was generally in the correct ball park figure.

I’m no physicist, but surely to move 30lbs up a hill requires twice the power that 15lbs does?

Yes, but it doesn’t take into account drag, prevailing weather, trail/road surface or how much you may be able to coast (which isn’t much during climbs but can make a difference on the flats).

Well I’m going to decide that 230W is Pro level and that if I can lose the 4stone extra I seem to ride with I’ll be quicker than a scolded Chris Froome

Well I’m going to decide that 230W is Pro level and that if I can lose the 4stone extra I seem to ride with I’ll be quicker than a scolded Chris Froome

If you can AVERAGE 230w for the whole of a decent ride that’s not bad going. Chris Froome wont be worried but your normal riding buddies should be.

I’m no physicist, but surely to move 30lbs up a hill requires twice the power that 15lbs does?

hilarious 🙂 Don’t you think the not inconsiderable weight of the rider might be included too ?

My observation is that I often see quite high power levels when I’m actually coasting at zero power 🙂

We’re all similar weights which is the only other variable that Strava has

you forget the GPSs. If they’re different types, or even turned on at different times, or with different settings, they’ll record different data points…

Ignore it unless you have a power meter my output varies from Will Hoy type power to couch potato depending on how strava is feeling 😉