By Alan Smeets
Certified Cycling Coach
Exercise physiologist & Sports nutritionist
Visit website to contact Alan

For cyclists who train with a power meter, Functional Threshold Power (FTP) is an important metric. Often a better FTP means better performance, especially if the FTP is expressed as power per kilogram of body weight. Many training plans use FTP to determine training zones. This article explains what FTP is, how to measure it, and what kind of training you should do to improve your FTP.

What is FTP and why is it important for cyclists

During exercise, all sorts of physiological processes take place in your body. If exercise intensity is low, your body converts energy by using oxygen (aerobic exercise), as intensity increases, the body converts energy without oxygen (anaerobic exercise). During anaerobic exercise, the body creates lactate, the burning sensation you feel during hard efforts. Your body is able to neutralize certain amounts of lactic acid.

At your threshold, the amount of lactate you produce during exercise equals the amount of lactate your body can neutralize. As the exercise gets more intense, the amount of lactate in the muscles will start to accumulate. Your threshold is also called Maximal Lactate Steady State (MLSS), the amount of power you produce at your threshold is called your Functional Threshold Power.

A higher FTP means you can produce more power before lactic acids start accumulating. Because your weight plays an important role in your climbing speed, FTP expressed per kilogram of body weight determines how fast a cyclist can climb uphill.

That’s because, when climbing, the dominant source of resistance to your forward motion is gravity. The gravitational force you have to overcome depends on your body weight. So a 60kg cyclist producing 240 Watt (4 W/kg) will get to the top faster than a 90kg cyclist producing 240 Watt (2.6 W/kg). Finally, FTP is often used to determine your training zones.

FTP tests to determine your Functional Threshold Power (FTP)

The best way to determine your FTP is through a laboratory test. Not everyone has the possibility to perform such a test. An alternative is the FTP test. With this test, you can make a reasonable estimate of your threshold power. However, there are many disadvantages to this test, and you can find many variants of this test.

The FTP test is a 20-minute time trial that you try to complete as fast as possible. After a good warm-up, you do two hard efforts of four to five minutes. After a short recovery, you start the 20-minute time trial, it is important that your power output is high but remains constant.

After your 20-minute test you can find your best 20-minute power in the data. Your FTP is about 95% of your best 20 minute power. It’s an easy way to estimate your threshold power but you need a good coach to interpret these results.

What determines your FTP

To figure out what training you should do to improve your FTP, you need to know what is happening in your body and what determines your FTP. First of all, your VO2 max is important as to where your FTP is in relation to your VO2 max.

One of the most important components of your FTP is your VO2max which is the maximum amount of oxygen your body can use during exercise. VO2max is thus the maximum capacity for aerobic energy production. FTP, on the other hand, is the highest power output you can sustain for an extended period of time relative to your VO2max. In most cases, a higher VO2max also results in a higher FTP.

In a lab test, you can find your maximum power output at your VO2max, this is not your maximum sprint power. In professional cyclists, the FTP is around 90% of their VO2max, in less trained cyclists it is a lot lower. You can improve your FTP by improving your VO2max but also by improving the percentage at which your FTP lies relative to your VO2max. So there is both an aerobic and anaerobic component to your FTP.

Types of training to improve your FTP

1. Endurance Training

Endurance training is important to improve your FTP. If your endurance base improves, your FTP also improves. You don’t have to do six hours of endurance rides to improve your endurance base, as long as the intensity is low enough.

For a professional cyclist, longer training sessions are more important than for cyclists who have less time. If the intensity is low enough a 90-minute workout can be good endurance training. Less experienced cyclists often perform their endurance rides at an intensity that is too high, resulting in a much lower training effect.

2. Tempo/Sweet Spot Training

Tempo or sweet spot training is performed just below your FTP. Because lactate accumulation is low, you don’t build up much fatigue in this zone, allowing you to train longer and closer to your current FTP.

Whereas these workouts were very popular in the past, they are used less nowadays as heavier intervals prove to be slightly more effective. In the winter period, this intensity is ideal for strength training on the bike with a low pedaling frequency.

3. Threshold Training

Threshold training is performed at or above your FTP. At this intensity, the lactic acid build-up is high, which means you fatigue a lot and recovery takes longer. Threshold training is therefore only recommended if your endurance base is good enough. By training at this intensity, your body will neutralize the lactate build-up faster so that you can produce more power before your body starts to build lactate, this improves your FTP.

4. VO2max Training

VO2max training aims to improve your VO2max. If your VO2 max improves, this will result in a higher FTP. You cannot do this type of training indefinitely because the fatigue you build up is very high, besides, too much of this type of effort can cause your endurance base to decrease again. VO2 max intervals are short intervals of 2 to 5 minutes above your FTP. High-Intensity Interval Training (HIIT) is performed at more than 90% of your VO2 max.

Summary

Functional Threshold Power is an important metric for cyclists who train with a power meter, as it correlates highly with performance. If you’re looking for specific examples with detailed step-by-step explanations this article from Train Right will provide more information you can use in your next training.

There are a few different ways to measure FTP, but the most accurate method is through a field test. Once you know your FTP, you can use training zones to improve your cycling performance. With focused and targeted training, you can see significant improvements in your FTP – and subsequently, your cycling times.