Functional Threshold Power (FTP) is one of the most critical metrics for cyclists looking to optimize their training. By doing an FTP test, we can accurately measure your FTP and tailor your workouts to hit the right intensities, making the most of every session.

In this guide, I’ll walk you through how to run a good FTP test, how to use the results to improve your endurance training, and some common mistakes to avoid.

Understanding FTP: What It Is and Why It Matters

FTP stands for Functional Threshold Power, which is an estimate of your second physiological threshold. This threshold marks the boundary between medium and high-intensity efforts. But what does that mean for your training?

Medium intensity is when you’re working hard—your legs are feeling it, your breathing is up, but you can sustain the effort for several minutes, even up to an hour. High-intensity efforts, on the other hand, are much more challenging.

You’re pushing your limits, breathing heavily, and the effort feels significantly harder. Think of it as the difference between a long, hard climb and an all-out sprint.

FTP is crucial because it helps you distinguish between these two intensities. This distinction allows you to plan your training more effectively.

For instance, threshold training (around your FTP) and VO2 max sessions (above your FTP) are both important, but they serve different purposes. Knowing your FTP ensures you’re training in the right zones to achieve your specific goals.

Some other terms you might hear related to FTP include Critical Power, Lactate Threshold, and Maximum Lactate Steady State. While these are slightly different measurements, they all aim to pinpoint that same transition from medium to high intensity.

Origins of the FTP Test: The 60-Minute Challenge

The original FTP test was a 60-minute maximal effort, developed by Dr Andy Coggan, a pioneer in power-based training. The idea was simple: most well-trained cyclists can hold their second threshold for about an hour. So, by riding at maximum effort for 60 minutes, you can estimate your FTP.

However, 60 minutes at max effort is brutal, even for seasoned cyclists. That’s why many people now use a modified version of the test—a 20-minute effort followed by a calculation to estimate the 60-minute power.

Here’s how it works: after a thorough warm-up, you do a 5-minute all-out effort to deplete your anaerobic capacity (known as W’ or W prime). This step is crucial because it ensures that during the 20-minute test, you’re working at your true threshold power rather than above it. After a short break, you then go all-out for 20 minutes. To estimate your 60-minute FTP, take 95% of your average power from this 20-minute effort.

Some athletes skip the 5-minute effort and simply take 95% of their 20-minute power, but this can lead to an overestimation of FTP, especially for those with a powerful, muscular profile. For most people, it’s safer to take 85% of the 20-minute power to estimate FTP.

Running a Good FTP Test: Three Essential Steps

Now that you understand what FTP is and why it’s important, let’s dive into how to conduct a good FTP test. There are three main stages: warming up, pacing, and calculating your FTP.

1. Warm-Up Thoroughly Before Your Test

A good warm-up is essential for a successful FTP test. You want your body to be ready to perform at its best. I recommend a warm-up lasting 20 to 30 minutes. This might seem like a lot, but trust me, it makes a huge difference.

Start with 10 to 12 minutes of easy riding to get the blood flowing. Then, perform a series of escalating efforts: 30 seconds at medium intensity (5 or 6 out of 10 on the difficulty scale), followed by 30 seconds of easy riding. Gradually increase the intensity over several rounds until you’re hitting about 8 or 9 out of 10.

Finish your warm-up with a few short intervals at the power you’re aiming to hold during the 20-minute test. After this, take a short break—have some water, let your heart rate come down, and then get ready to start the test.

2. Pace Your Effort Over the 20 Minutes

The key to a good FTP test is pacing. You don’t want to go all-out from the start and burn out halfway through. Instead, break the 20 minutes into four 5-minute segments.

For the first 5 minutes, aim for about 7.5 out of 10 on the difficulty scale. This should feel hard, but manageable. For the second 5 minutes, increase the intensity to about 8.5 out of 10. The third segment should be even harder—around 9 to 9.5 out of 10. Finally, for the last 5 minutes, give it everything you’ve got. This should be a 10 out of 10 effort, where you’re pushing to your absolute limit.

The goal is to finish strong, gradually increasing your intensity throughout the test. If you pace it right, your final 5 minutes will be your hardest, and you’ll achieve your best possible average power over the full 20 minutes.

3. Calculate Your FTP Correctly

After the test, it’s time to calculate your FTP. As mentioned earlier, take 85% of your 20-minute average power to estimate your 60-minute FTP. This number is your Functional Threshold Power, and it’s the key to tailoring your training zones.

With your FTP in hand, you can now set precise training intensities for different types of workouts. For threshold sessions, aim to stay just below your FTP. This allows you to sustain efforts for longer periods, which is essential for pushing your threshold higher over time. For VO2 max intervals or high-intensity training, you’ll want to go above your FTP, focusing on shorter, more intense efforts that improve your ability to perform at high intensities.

Common Mistakes to Avoid When Running an FTP Test

Running an FTP test isn’t just about going hard for 20 minutes. There are a few common mistakes that can skew your results and impact your training.

1. Not Warming Up Properly

Skipping or cutting short your warm-up is a big mistake. Your muscles and cardiovascular system need to be fully prepared to perform at their best. A half-hearted warm-up means you’ll start your test underprepared, and your performance will suffer.

2. Misusing FTP to Calculate Training Zones

While FTP is an excellent marker for threshold training, it’s not a perfect predictor for all training zones, especially Zone 2 (aerobic endurance). Many cyclists make the mistake of calculating Zone 2 as a fixed percentage of FTP, but this can vary based on individual fitness levels and training backgrounds. Use other methods, such as heart rate or perceived exertion, to ensure you’re truly training in the right zone.

3. Overestimating Your FTP

Some athletes overestimate their FTP by using their 20-minute power as their FTP or by taking too high a percentage of it. This can lead to training at intensities that are too high, which can cause overreaching or stagnation in performance.

Stick to 85% of your 20-minute power for a more realistic estimate, and adjust as needed based on how your body responds in training.

By avoiding these mistakes and following the steps outlined above, you can ensure that your FTP test is accurate and that the results will help you train more effectively.

The Importance of Accurate FTP Testing

Running a good FTP test is about more than just pushing yourself to the limit—it’s about understanding your body, pacing your effort, and using the results to tailor your training. With an accurate FTP, you can individualize your cycling sessions, ensuring that you’re training at the right intensities to improve your performance.

Remember, it’s not just about the test itself but how you use the results in your training. Whether you’re aiming to boost your threshold power, enhance your endurance, or improve your high-intensity performance, knowing your FTP is key.

I hope this guide helps you run a successful FTP test and get the most out of your cycling training. If you have any questions or want to share your experience with FTP testing, feel free to leave a comment below. Happy training!