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Critical Power testing

rabkrabk Posts: 182
I've just got my new powertap pro + hub built up into a wheel and have been reading up on how to train with power.

Essentially it seems I first need to go about identifying my power decay curve through testing for various CP (critical power) levels.

My question is when doing these tests, do I try and do them all on the same day, or perhaps only one or 2 at a time. I was thinking of doing my cp12 and CP30 tomorrow.

I have had an easy week or so, so should be rested enough to give it a bash tomorrow, but just wanted to check with people who are more experienced how you do your testing

I did find a power profile test which seemed to suggest that all are done in one go, but assume this would meean that some of the figures are not accurate.


  • So long as your method is consistent the next time you do it, it doesn't matter IMO.
  • GiantMikeGiantMike Posts: 3,139
    I just do a CP20 test and derive other figures from that. At the end of any test you should be pretty fecked which makes it silly to go from one to another.
  • drudru Posts: 1,341
    If you have access to a turbo trainer I would agree that a CP20 will help you out and or complete a ramp test.

    The regular testing of a CP20 for instance will show improvement etc etc
  • There is only one critical power (as defined in exercise physiology terms).

    To establish it, you need a minimum of two tests. I find that one test of between 4-6 minutes and another of between 20-30 minutes is good, provided they are well paced maximal efforts. Each to be completed within the same week. You can add a 3rd test if you like (e.g. your 12-min test) but it's not necessary. It is better to have two really good data points than three less reliable ones.

    Doing tests on same day may impact results as one element of the critical power model is to establish your anaerobic work capacity (in joules) and that requires you to have exhausted your AWC during each test. If you start a test with a partially depleted AWC, it will affect the outcome.
  • rabkrabk Posts: 182
    Thanks guys

    Appreciate the responses. Will take your advice and do a 30 min test tomorrow and perhaps a 6 at some point next week.
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