Determining FTP: a brief history of FTP and how to do it the Sans Chaine way

No one number can define you as a rider. Each of us has different abilities, a unique combination of the development of our aerobic and anaerobic systems. However, in the world of cycling Functional Threshold Power (FTP) has become ubiquitous as the one absolute metric that defines our fitness and strength. Before we discuss how to determine your FTP with Sans Chaine, a bit of background.

For many, FTP has become the primary measure of a cyclist’s ability. It is how many training programs define their training zones and the number on which our structured workouts are built. It is not however a metric without controversy. At Sans Chaine we are not true FTP believers as the be all and end all, but given how important FTP is to our use of cycling technology - think indoor training and our structured workouts - it is necessary to define FTP for each of us.

Commonly you will see FTP defined as our maximum one hour effort, perhaps even a one-hour race effort. This however isn’t quite correct.

A better definition comes from Andy Coggan, who developed the FTP concept: The highest power output that a cyclist can maintain in a quasi-steady-state without fatigue for approximately 60 min.

In this definition we can see that it isn’t specifically a one-hour effort, but rather an approximation. Our ability at FTP, where our effort is quasi-stable, can be less than or slightly more than one-hour. Lets be clear, FTP is not a one-hour time trial, as many describe it. A well paced time trial should leave us completely spent and very fatigued. Understanding these key elements about the definition of FTP is important in getting your FTP right, so that your training will be sustainable and repeatable. Consistency is king.

The quasi-stable concept comes from the fact that FTP is meant to model an effort at which the lactate levels in our blood are stable - referred to as Maximal Lactate Steady State (MLSS). MLSS is based on lactate and lab testing and quite likely falls within your tempo range. For the purposes of how FTP is applied within the cycling community using the MLSS number as your FTP would be too low.

Confused? Many cyclists are and what happens is that they either train too hard or too easy and they are not able to see sustained progress over time. Many cyclists then give up on training and that is why Sans Chaine has developed a way to use this metric, overlaid with other inputs, in a way that will help you progress in a manner that is sustainable.

How to estimate your FTP with Sans Chaine

When training with Sans Chaine you will use two estimates to determine FTP. Between these two estimates you will have to make a decision what is the right FTP for you. The danger in the estimation of FTP is that it is often overestimated, leading to power training zones that are too hard. At Sans Chaine we mitigate this problem by developing power training zones from Maximum Aerobic Power (MAP), a number we can test directly, and overlaying our heart rate zones to create even greater context as to how the workout is affecting you.

In your testing week you will have done two time trials, 5-minutes and 20-minutes. To determine FTP we will take percentages of each effort. For our first estimate you will take 80% of your average wattage from the 5-minute time trial. The second estimate will be 95% of your average wattage from the 20-minute time trial.

The difference in the estimates you get will depend on the relative strengths of your aerobic and anaerobic systems. Blending these estimates will give you an FTP number that is in line with your actual abilities.

As a rider you can have a strong aerobic system and weak VO2 ability, or vice versa. No one number can be used to define your training. Training with Sans Chaine means learning to rely on multiple inputs - target wattage, wattage training zones, heart rate training zones, and perceived exertion - to make decisions each day about your training.

Overarching these inputs is the concept that our decision to train and be cyclists is a lifestyle choice. The choice gives us a long-term lens through which to make our training decisions, striving for consistency, which will ultimately lead to better riding. All hail the king - consistency!

Want to read more about whether FTP is valid? Here is a good article with plenty of data: https://www.cyclingapps.net/blog/is-ftp-physiologically-real-or-does-it-exist-only-in-coggans-imagination/