The Power Meter Handbook: A User’s Guide for Cyclists and Triathletes

eliminates all of the scientific mumbo jumbo about lactate and the out-of-pocket cost associated with doing a lab or clinic test. It’s also a real-world solution, meaning that it directly translates to the reality of racing out on the road. Races are not conducted in labs or clinics on stationary ergometers. Dr. Coggan’s concept avoids all that in favor of a measurement taken from the roads you already ride.
Determining Your FTP
    Dr. Coggan’s method for determining your FTP is not perfect. The major problem is the need to do a 60-minute test. Such a field test would certainly challenge your capacity for suffering. It takes great focus and motivation for anyone to go out on the road or get on an indoor trainer (an off-road trail would not be suitable for the test) and ride a solo workout as hard as possible for 60 minutes. Fortunately, there are other ways of finding your FTP that don’t require such a long, agonizing sufferfest. Here are some of the more common alternatives, from the most reliable to the least.
    Races. Do you have a local bicycle time trial that’s available, especially one that would take you about an hour to complete? Your average power for such an event would be precisely what you need for calculating FTP. A 40-km time trial would be about right for many athletes. The 40-km leg of a triathlon or duathlon would not, however, as in those events you have to hold back on the bike in order to run well. That would skew the results and make the numbers a bit too low.
    Almost as good as a time trial is a 1-hour criterium for road cyclists. Even though it’s not steady, a rider’s NP for such a race is usually quite close to FTP if the race is a hard one. But if the field sits up and lets the break ride away, then the results are unlikely to accurately predict FTP. You need a solid hour of hard racing to make the measurement useful. This is when Normalized Power really shines in comparison with average power as it takes into account the positive and negative spikes in power production common for such races. For a well-paced time trial (more on pacing shortly), the difference between Normalized Power and average power will be inconsequential.
    The race you use could even be a time trial or criterium that lasts less than 1 hour. But let’s stop and consider an important point here before gettinginto the details. Whenever we have a test duration that isn’t 1 hour, we are in the realm of estimating rather than measuring FTP. That opens the door for error. And the further the test is from 1 hour, the greater is the potential for error. So bear in mind that what I’m going to explain from here on in this entire section isn’t as accurate as doing a 1-hour race as a test. But you probably won’t be off by much if we keep the difference to 30 minutes or less.
    Let’s say you are going to use a shorter race for estimating FTP. In this case, you’d apply the 5 Percent Rule described in Chapter 3 . To refresh your memory, the 5 Percent Rule says that when the duration of a maximal effort is doubled, the power decreases by about 5 percent. This means that if you did a time trial or criterium race that took about 30 minutes, you would subtract 5 percent to estimate FTP.
    For example, let’s say you did a 20-km time trial in 30 minutes and your average power was 260 watts. By subtracting 5 percent (13 watts), you would estimate that your FTP is 247 watts (260 – 13 = 247). Even if your time was a few minutes more or less than 30 minutes, perhaps between 25 and 35 minutes, we could draw the same conclusion since it’s only an estimate anyway. What you should be doing is closely monitoring several different methods of estimating FTP and drawing conclusions from all of them in order to make your FTP more precise.
    30-minute test. Although a 1-hour race is the best way to determine FTP, you can do a field test instead, and one that is shorter than 60 minutes. This is the most common method I use with the athletes whom I coach and with whom I consult. It’s simple. Warm up, then ride on the road (not a trail, if you’re a mountain biker) or an indoor trainer for 30 minutes as hard as you can. (Note: Most riders find that doing this test on an indoor trainer is muchmore difficult.) Your average power is a good estimate of your FTP without your even subtracting the 5 percent described above. I’ll explain this because it seems contrary to what I said earlier.
    When you do a race, you will always push