Alpe d’Huez

I am planning to ride up alpe dHuez this summer.
My training includes sessions going up alpe du zwift.
I have an 11/32 cassette and a 52 chainring on my trainer bike.
I have the trainer difficulty set at 50%
I can climb alpe du zwift in 90 mins.
To get an accurate feel on my trainer for what will be in store for me this summer, similar bike gearing, do i need to put trainer hardness serting to 100%
Thanks for any insight

I hope you have something smaller than a 52 as well. Climbing IRL on a 52 will be crazy.

I would think closer to 100% will be better but go outside on a climb and see what gears and rpm you climb at then find the same climb on Zwift and see if it is the same.


From your description, a 52/36 11-32 combination wouldn’t be ideal.

IRL I have used 52-36 and 11-28 in the Alps (a Mavic provided Canyon Aeroad CF SLX) or 50-34 and 11-32 on my own bike. The Mavic machine was a lovely bike but harder work when things got steep. I don’t use the 30 and 32 often, but they are there if needed.

You want the easier gearing in case your legs die, especially if you are riding not just Alp D’Huez but some of the other routes nearby like Glandon, Sarenne or Madeleine.

For comparison I did ADZ yesterday twice, first lap 48 minutes second lap 47 minutes. I’m 59kg. Even with that I’d still go compact chainring IRL just in case.

Also remember that in Zwift you are still at normal altitude, so that’s also a difference to IRL.

Ride ADZ as much as you can on Zwift ahead of your event, and don’t use workout mode, slogging away in workout mode at constant power doesn’t give you the feel of the gradient changes and adjusting your power or using the gears.


I wouldn’t increase your trainer difficulty from 50% to 100% in one go. That would probably be too much of a shock to your system and potentially off-putting that you can even do it, if you take 90 minutes at 50%.

Increase it in stages to gradually get used to the higher resistance. As the others have said, I suspect you’re going to need some lower gears at 100% difficulty and on the real thing. But you’ll start to get a feel for that as you get that TD higher.

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That is an excellent idea!! RE: finding something outside to calibrate similar inside.
I spoke with my bike shop and they are going to set me up with new power train that will be appropriate


48 min… maybe I just just need you and tow rope :grinning:
I called my local and they are going to set me up with appropriate gears.
And I will just keep going up on zwift.


Thanks! And good suggestion to increase slowly. I want a can do attitude as opposed to I will die on this hill.


Meh, I say send it, go on and set your TD to 100%. Maybe do a few easier climbs (Volcano, Epic KOM) at 100% before diving straight into the Alpe, but if you ride hills outdoors you should be fine. Do get some better gearing first though. As others have mentioned, 52-32 will be horrendous at TD 100% on the Alpe. I’ve got a standard double (53-39) and 11-28 cassette and my 39-28 granny gear is a bit of a grind over 10%, but I’m also not very good at this. I’m hoping to switch to a 50-34 compact crank this year.

Grinding away in your lowest gear can work for one or two climbs, but if you have multiple days of them - such as say Haute Route Alps, Pyrenees or Dolomites then it’s not sustainable, even with the massage at the end of each stage. Every day is at least 3000m+, sometimes even 4700m+, the only rest is a TT at maybe 1200m+ over ~12km. That’s tough so being able to spin makes it easier.

If you need even smaller than 50-34 then go for it, whatever you need to get you up and down the mountains.

I Zwift with a 52 CR and a 11-28 cassette.
I’m the old man of our bike club and IRL I still use a triple crank and let me tell you, there is more than 1 time per season I’m glad I have that option.

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