Organize this short test (5 to 6 minutes of maximum effort) makes it possible to define and compare at least one value for which we know that the physical commitment was maximum without generating fatigue which would hamper the next training to come.
The Maximum Mean Power (or MMP) is the cycling expression of VO2. This data corresponds to the maximum power developed while remaining mainly in the aerobic sector, therefore with limited lactic assistance.
Developing more power than MMP over this 5-minute period would generate too much lactate and H+ ion production, which would hinder effort in the short term. Exhaustion would appear at the end of the test.
Developing less power will be an effort in endurance but without stimulating to the maximum all the energy supply systems of the organism and as we wish to define our maximum limits in energy level through this test ....
The advantage of the test is its ease of implementation and it is also possible to repeat it regularly during the season to assess the fitness level (every 4-5 months). However, in this case, you will not have oxygen input or lactate production data as in a medical test.
For my part, I like to do it 5 to 7 weeks before an important race to have an objective vision of the cyclist's abilities and to be able to adjust the training if necessary.
Let’s set up a progressive warm-up to join a regular and long hill of at least 2 km (if you do not have a hilly road as long, the test can be done with connected turbo-trainers).
Once ready, let’s start a 5 min time-trial. Do not leave on a slope too steep to have the possibility of playing the rear derailleur and not be limited by your cassette. The average power obtained at the end of this effort corresponds to the MMP.
The interest is to be able to repeat your test on this same road when necessary but beware of the weather conditions which must be relatively neutral (no high or low temperatures, no wind, dry pavement) to be reproducible.
In the same way, it is important to carry out the same warm-up, over the same duration in order to present yourself on the same hill for this CP5-test.
Here, the CP5 (MMP) represents 307 watts of normalized power. From this test, supplemented by the PPR, we can evaluate the athlete's fitness and his progress. In addition, we can establish all the pacing necessary to achieve a full race and quality training.
For my part, I do not add a CP20-test to extrapolate CP60. The CP60 corresponds to what the US calls the FTP (Functional Threshold Power), the anaerobic threshold.
The accumulation of data during HIT sessions and races makes it possible to obtain completely valid data.
You could argue that it takes time to compile valid data and that before having a reliable FTP, the Intensity Factor or TSS (Training Stress Score) indices will be distorted and therefore the training load (TL) management at the same time. But I think that it is very limited to evaluate the TL only with numbers, that does not bother me more than that.
If we build our training around a percentage of FTP and not MMP as modeled by Coggan, we need to have a reliable CP60. But Erin Calaine Inglis and coll. have just demonstrated it recently, there are too large variations in data if we use CP20 to extrapolate CP60 (CP60 = 95% CP20). There will, therefore, be obvious errors in the definition of effort targets.
 Maximal Lactate Steady State Versus the 20-Minute Functional Threshold Power Test in Well-Trained Individuals: “Watts” the Big Deal? Erin Calaine Ingli and coll. , 2019.