FTP is a cycling metric that stands for Functional Threshold Power. It estimates the highest average power you can sustain for one hour, measured in watts. In cycling, FTP is a measure of fitness and indicates the amount of work you can sustain for long durations. Additionally, it’s used to determine power zones used in training.

For more information on training with power, check out Ask a Cycling Coach Ep 195.

Cycling FTP Definition

Function Threshold Power (FTP) is a measure of your cycling fitness and ability to maintain a high but manageable power output for a somewhat lengthy duration. From a physiological perspective, it’s the cycling power you produce when your lactate production has risen, leveled off, and then closely matches your body’s ability to remove lactate. This just barely keeps that lactate flooding at bay. In cycling, FTP is that grey area between the power you can sustain for a very long duration, typically an hour, and the fleeting power you can only tolerate for a couple of minutes.

Adaptive Training

Get the right workout, every time with training that adapts to you.

Check Out TrainerRoad

When you are cycling, FTP is the balance point between energy supply and demand. Specifically, FTP is the balance between your aerobic and anaerobic energy systems. When you are cycling at low intensities, you are using your aerobic system. The aerobic system uses oxygen to metabolize fuel to create the needed energy. When your aerobic system can meet the energy demands of your muscles, there’s less contribution from your anaerobic energy system.

However, when cycling at higher intensities, the anaerobic system contributes more. The anaerobic system metabolizes fuel sources without oxygen. It creates energy much faster but for a shorter time. Continue to ride at a high intensity, and the byproducts of the anaerobic system overwhelm your ability to clear them. So your breathing increases, the legs start to burn, and your time at this power output becomes minimal. Functional Threshold Power the harmony between energy systems.

What FTP Means for Cycling and Training

The primary reason FTP is an important metric is that it’s a quantifiable way to measure your cycling fitness while providing a framework to gauge the difficulty of your rides. Additionally, it serves as the basis of many other power-based training metrics like Training Stress Score and Intensity Factor.

For example, a cyclist completes an hour-long ride and finishes the ride with a Normalized Power (NP) of 200w. Normalized Power is a mathematically adjusted measurement of average power that smoothes out power spikes and coasting. Still, it really doesn’t tell us much about how hard the cyclist was working compared to their fitness level. Without knowing their FTP, we don’t know if this was an easy endurance ride or an incredibly difficult one.

Cycling FTP provides the context. Let’s assume this cyclist has a 300w FTP. That means that they rode at about 66.7%, which is an easier endurance ride. However, if their FTP was 210w, then the difficulty changes dramatically. Instead of an easy ride, they would have been riding at 95%, which is a hard thing to do for an hour.

FTP and training

This context is vital for training as well because the difficulty of cycling workouts needs to be scaled to your current fitness level. A structured training plan progressively trains the energy systems needed to grow your fitness. Using cycling power zones, each workout in a plan is designed to provide just enough training stimulus to drive the adaptations that make you a faster cyclist.

Here is a computer displaying a TrainerRoad workout. The FTP in cycling means the workout is scaled to an individuals fitness.
A correct Functional Threshold Power ensures that your cycling training is providing the right stimulus to make you faster.

Knowing your FTP ensures that every cycling workout is optimized to your current fitness level. Also, it will help you quantify the amount of training stress you are racking up. This is an important metric to track. Too little stress lacks the needed stimulus the body requires for adaptation. Too much, and you’ll overpower the body’s ability to recover. The good news is that TrainerRoad does both for you automatically. 

Why FTP is Important to Cyclists

Aside from properly scaled training, FTP is significant to cyclists for many reasons. For some, it’s a way to track their growing fitness and for others is a way to compare themselves to other riders. Here are some important ways to use FTP for cycling.

Cycling Performance

FTP comparisons between cyclists do not tell the entire story but can give some context to performance. It doesn’t reveal your maximum sprint power or repeatability. However, the higher your FTP, the faster you’ll be able to ride, especially on flat and rolling terrain. As you ride up steep, long climbs, power-to-weight becomes more important. W/kg is usually expressed as FTP divided by body weight in kilograms.

Pacing for Events

Long cycling events are all about energy management. Creating a pacing plan is an excellent way to ensure you not only finish but have fun while riding. With an accurate FTP, you can create a pacing plan for your next century, Gran Fondo, or gravel grinder. 

How Cyclists Test FTP

An FTP test is a physical assessment to evaluate your cycling fitness. The most obvious way to determine your cycling FTP is to ride as hard as you can for one hour. Your average power for the hour is your FTP. The problem is not only is that incredibly difficult, but it’s extremely fatiguing and hardly convenient. Here are some easier ways to get your FTP for cycling.

Ramp Test

Several different formats provide an accurate measurement. TrainerRoad’s preferred FTP assessment is our Ramp Test. The Ramp Test begins with a 5-minute warmup, then every minute thereafter, it gets slightly harder until you cannot maintain target power any longer. 75% of the best one-minute power you achieve during the test is used as your FTP. Our data shows the Ramp Test results in the most accurate and useful test for the majority of riders using TrainerRoad. Since it is quick (normally about 25 minutes) and fairly easy, you can frequently track changes in your fitness.

20 Minute Test

One of the best-known testing methods is a 20-minute test. You’ll ride at your highest sustainable power for 20 minutes. Your FTP is 95% of the average power during this interval. This format can be challenging to pace correctly and is best done when you have fresh legs and a bit of practice.

8 Minute Test

Slightly easier to pace than a 20-minute effort, the 8-minute FTP test is a more intense version. Just like the other, you’ll ride as hard as you can, avoiding surges, for eight minutes. Then you’ll rest for ten minutes and complete another eight-minute effort. Your FTP is 90% of the average power of the two efforts.

TrainerRoad training plans include regular FTP tests to ensure that every workout is scaled to your fitness level. At the beginning of every training block, you’ll complete the Ramp Test to ensure the most effective training. Additionally, training plans are designed to increase training stress progressively, thereby providing the stimulus for consistent and lasting fitness gains. Structured training is that stimulus, and stimulus paired with adequate recovery is precisely what you need to get faster.

For more cycling training knowledge, listen to Ask a Cycling Coach — the only podcast dedicated to making you a faster cyclist. New episodes are released weekly.