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Zwifters

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Angus Clydesdale Jun 2020 7:00pm, 6 Jun 2020 18,378 posts	Quote Pin Angus Clydesdale I know. Scary AF!!! 😂
simbil Jun 2020 8:37pm, 6 Jun 2020 8,681 posts	Quote Pin simbil Does the real world still have those crappy graphics Angus? Somewhere around 3 W/kg gets you up the Alpe in an hour.
MudMeanderer Jun 2020 9:40pm, 6 Jun 2020 1,896 posts	Quote Pin MudMeanderer Ndellar; I'm not sure exactly how sophisticated Zwift's algorithms are, but power to overcome drag varies as cube of velocity, and power to weight to overcome gravity varies as square of VAM (may need to check that - should do derivation on paper not in head). The balance between the two resistive components depends upon gradient and how fast you're going. Zwift adds in some parameters (e.g. for how aero you can get), but in theory if you have the instantaneous speed and power of a rider at a particular point on a climb, and their weight, you can calculate the speed of a rider with different power and weight. Over sustained steady climbs you could use average data. If you only have power and weight data, you could bound the likely times by considering all resistance comes from one source, and then from the other source. So it can be done, but not necessarily a trivial in your head calc.
Gobi Jun 2020 10:09pm, 6 Jun 2020 70,050 posts	Quote Pin Gobi Nat - you can look at your race numbers - check what 95% of you 20 min effort is. That will tell you at effort what you will hold for an hour( approx) there are tables on zwiftinsider that tell you wkg = x time up alpe . Ie 4.5wkg to break 45 mins .
MudMeanderer Jun 2020 10:09pm, 6 Jun 2020 1,897 posts	Quote Pin MudMeanderer Correction: VAM varies linearly with power to weight, so the upper bound on time (strictly only true as velocity tends to zero) can be estimated fairly easily. It means if you half the power to weight ratio, it should take no more than twice as long to cover the same vertical distance.
Angus Clydesdale Jun 2020 1:45am, 7 Jun 2020 18,384 posts	Quote Pin Angus Clydesdale Thing is, my Young Lad "cruises" up the Alpe at ~4w/kg and turns in a 56:xx finish and I look at his w and think, "that's cool 200w will get me up there" and then I have the horrific realisation that 200w might be 4w/kg for him but it’s not even 2w/kg for me. And then I realise that at the moment I can barely maintain ~200w for 20 mins, let alone 60+ Anyway, food for thought. Talking about food, celery stick anyone?....
Gobi Jun 2020 8:14am, 7 Jun 2020 70,055 posts	Quote Pin Gobi Angus couple of good reads zwiftinsider.com This says the boy should be sub 50 if at 4wkg ! zwiftinsider.com Cruises at 4WKG means he needs to race and would be in with me :¬)
MudMeanderer Jun 2020 10:18am, 7 Jun 2020 1,898 posts	Quote Pin MudMeanderer I tempoed up the Alpe in around 57mins at around 3.5w/kg (~200w @ 57kg - I'm not real human size!), so that agrees with my experience. Racing in the higher categories at that weight is challenging (at least on the flatter courses I've done), especially when coupled with my lack of acceleration. Being pint sized doesn't count for much until the road points up steeply!
ndellar Jun 2020 1:57pm, 7 Jun 2020 3,642 posts	Quote Pin ndellar Currently doing some of the Alpe - not sure today is the day to get to the top!
ndellar Jun 2020 3:07pm, 7 Jun 2020 3,643 posts	Quote Pin ndellar Well I got to Hairpin 11 and turned around. I like the fact it breaks it down in to sections and there is a bit of flattening on the hairpins. It felt ok but I ran out of time really as I’m working this weekend. Confident with a longer time window next time I’ll get to the top, if there is one thing I can do it’s a steady plod! Was a good way to get a lot of climb crammed in a short space of time though. Such fun going back down. Weeeee!