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

yourself harder than in a workout. In workouts there’s nothing on the line. There are no awards, no podiums, and no pats on the back. So we just don’t work as hard as we are capable of doing in a race. We are much more likely to feel a bit sorry for ourselves in a workout and so back off—but only slightly. How much easier do we ride? About 5 percent. How cool is that? We’ve canceled out the 5 Percent Rule by doing the 30 minutes as a workout instead of a race. That means a 30-minute solo test is about the same as a 60-minute race when it comes to your average power. But notice that I said solo. You can’t do a 30-minute field test with a training partner or in a group. That changes everything. In that case you’d need to subtract 5 percent.
    Pacing this test is the challenge, especially the first few times you do it. The more times you do the 30-minute FTP-determination test, the better you’ll get at pacing. At first, however, you’re likely to start too fast and then fade as the test progresses. That’s likely to produce an average power that’s inaccurate. Here’s how to pace the test. Start with what you believe or know your FTP to have been from a recent race, test, or other method as described below (including estimation based on weight and personal modifiers). Hold this power for the first 10 minutes of the test. At that point, decide if the power you are maintaining is too hard or too easy, and then make an adjustment up or down accordingly. Repeat this self-assessment of power every 5 minutes thereafter until you are done. Your average power for the entire 30 minutes will be a good estimation of your FTP.
    To help the accuracy of this method, you must keep conditions similar from test to test. That includes such variables as riding on the road or anindoor trainer, the course you use, the time of day for the test, warm-up, equipment (including tire pressure), weather conditions, rest status, and pre-ride food and drink. There will likely be some conditions that change from one test to the next. The most likely is weather. But control as many as you can for the sake of accuracy.
    Workouts. While riding, pay attention to your perceived exertion, especially when doing steady efforts for several minutes, as when climbing a hill. Whenever you sense that your exertion level is steady at about 7 on a 0 (low) to 10 (high) scale, look at your current wattage. It’s likely close to your FTP. You could also use your software graph of the ride to find these segments after the workout. These are estimations that should help you to narrow down the range in which your FTP is likely to be found.
    Heart rate. Don’t use your heart rate zones to set your power zones. For example, when riding in heart rate zone 2, you are not necessarily going to be in power zone 2. You may recall from Chapter 3 that this is because heart rate zones stay relatively stable, while power zones change significantly relative to fitness changes. Although the two zones may overlap quite a bit early in the training season when fitness is low, the overlap will decrease as your fitness increases. The only heart rate and power numbers that may be the same, or at least close, are your LTHR and FTP. When riding steadily for several minutes at LTHR, you should be about at your FTP, so that is one simple way of estimating it.
    Here is a simple way of testing for an estimated FTP based on LTHR. On an indoor bicycle trainer, warm up for 10 to 20 minutes. Then start a graded-exercise test consisting of several 4-minute stages separated by 1-minute recoveries. The first stage begins at a power that is roughly 80 watts belowwhat you currently think your FTP is based on race data, previous testing, or a rough estimation as suggested below. Each subsequent work stage is increased by 10 watts. You’ll have to watch the head unit closely, being sure to stay at the prescribed wattage for each stage. Pedal for 4 minutes at a comfortable cadence in whatever gear allows you to create this power output; observe the response of your heart rate. It will gradually increase in the first minute or two and then stabilize for the remainder. At the end of each 4-minute stage, pedal at a very easy effort for 1 minute. Then start the next stage. This continues until the stage in which LTHR is observed. Be sure to finish that 4-minute stage. The average power for this last stage should be close to your FTP.
    Estimation. This could be the least accurate way of coming