In our last post we covered why and how to properly test your Functional Threshold Power or FTP, including some strategies to help you test your best (and even make it fun!). If you missed that post, you can find it here.
So now that we know the importance of testing and how to test properly, what else do we need to know in order for the test to be useful? Well there isn’t much point in doing a test (especially one as unpleasant) if it won’t have some training benefit, and for most of us that benefit is defined as a faster bike split – whether in a short or long course race
So what is a “good” number?
I often tell clients not to think of the FTP test as a test in the strict sense of the word, but rather an experiment. That is, you cannot pass or fail an FTP test, you can only do your best – and if you truly do your best, you’ll have a useful benchmark for future training and a tool for race pacing.
Separate your ego from your FTP number and avoid comparing results to those of others. If you can look at it in that dispassionate, scientific sense, your FTP is a powerful tool. Use it and the resultant training zones to get better, stronger, faster.
So what’s a good a number? Your best: legs burning, near hurling, lung screaming, not quitting, all out test is a good number. End of story.
Establishing Training Zones
Once you have those hard-won threshold power digits what next?
Set up your zones, of course. The most commonly used scheme was proposed in the widely accepted work of exercise physiologist Andrew Coggan. His zones as percentage of FTP are as follows:
Z1 Recovery: <55%
Z2 Aerobic Endurance: 56% – 75%
Z3 Tempo: 76% – 90%
Z4 Threshold: 90% – 105%
Z5 VO2max: 106% – 120%
Z6 Anaerobic Capacity: >121%
With these zones in hand, you or your coach can now design workouts that stimulate specific physiological adaptations. The idea being to develop base endurance, train underperforming aspects, and prepare for specific race demands.
Other Considerations for Testing
It’s not quite as simple as sitting on your bike and hammering out a solid twenty minutes as hard as you can go. To get the most out of your FTP test, consider some of the following.
Aero position vs. Sitting up
Always aero. No question. You should endeavour to train in the position in which you race. You don’t race sitting up, so you shouldn’t train or test that way. It’s true that most of us can generate a few more watts sitting tall, but the aerodynamic costs are substantial.
I once had a friend tell me that his FTP number was way higher than my own, yet my race results were consistently better. I asked him how he tested, and sure enough, he was on the horns the whole time and out of the saddle when his legs started to burn. Sure he was able to post a higher number, but that result wasn’t all that useful as it was not representative of his riding position in training and racing.
Outside vs. on the Trainer
Outdoor testing is a dream. It’s much easier for most of us to be motivated outdoors.
It’s entirely impractical however. Even if you could find a flat ten to fifteen kilometers of uninterrupted, traffic-free tarmac, you’d never have the temperature or the humidity the same on subsequent retests. Remember that the FTP test is a scientific experiment disguised as masochism. For that experiment to be a success, you must endeavour to control as many variables as possible and keep them constant from one test to the next.
Testing in a Race
Testing in a race is a fine idea, provided you have some long, uninterrupted stretches and few turns. A flat race is preferred too as it reduces the temptation to pop out of aero when climbing. The Welland long sprint is the only event that comes to mind that may work okay. You likely won’t get a full twenty minutes, but it’ll be close.
Also a test result from a race shouldn’t really be compared to one done indoors. It can, however, be a very good ‘last’ test before a big race.
Discrepancies Between Power Meters and Power-Based Trainers
Without getting too bogged down in a conversation of accuracy versus repeatability, it’s sufficient to note that most power meter brands will differ in their readings slightly. That is, if you are riding a bike with both a rear hub mounted Powertap and a crank mounted Power2Max, each powermeter will read a slightly different value. Most of this actually depends on where the powermeter is located. Due to drivetrain losses – mostly bearing and chain friction – the closer the powermeter is to your foot, the higher the reading. Pedal meters tend to read higher than crank based ones, which are higher than rear hub based models.
Power-based trainers like the Computrainer tend to have the greatest discrepancies as they rely of correct calibration to account for tire pressure and tension knob adjustment, etc.
Why should you care? It’s true that so long as you’re getting consistent readings from your meter or trainer, then your training will be sound. The only circumstance where it pays to take care is when switching between powermeters or going from a computrainer to a powermeter. You will likely need to adjust FTP and zones.
Part 3: How to Boost FTP
In our final article we’ll go through some popular workouts to boost your FTP.