Real-Time FTP Determination

Never Do An FTP Test – The Sequel

Last year, we introduced the idea that there was no longer a need to do FTP tests when you use Xert.  This was quite remarkable at the time as athletes often planned and performed tests on a regular basis both during training and racing seasons in order to determine their level of fitness and performance expectations.  Alas, there are still many that use lactate testing with blood sampling to determine FTP.

Today, we announced a new Garmin app: What’s My FTP? with another novel and powerful approach to determining an athlete’s FTP:  we can detect it in real-time, on-the-fly.

The is quite the accomplishment as the method uses some sophisticated techniques and pattern recognition to determine your FTP.  Whereas in the past you either needed to test using a 20 minute FTP test for example or examine many months worth of data to get a realistic FTP value, this method enables you to determine your FTP on that day or even at that moment.

How Does the App Work?

The app is a simple Garmin Connect IQ Datafield.  Note that it does not connect or require an Xert account nor does it require any configuration, although there is an option show FTP in W/kg in the app settings.  You simply install the app as any other datafield on your Garmin and add it to your Activity Profile.  It supports a wide variety of Garmin devices so that you can run it on your bike computer or on your wearable.

In general, it’s best to use a dedicated screen for it but another approach is to use 2 fields on your data screen with Power and the My FTP app.  This enables you to see your power and where you are relative to the effort needed to get your FTP to move upwards.


The best approach to getting great results is to do a ride where you know you’ll eventually be brought to your limit.  Sometimes there’s a climb that you repeat until you legs give in.  Sometimes you can give it all in a crit.  Sometimes you reach your limit when you get dropped. Whenever you reach a point-of-failure, the app will provide a value for your FTP.

You’ll notice that during your ride, race or workout, the dial moves clockwise until it reaches 12 o’clock.  You’ll initially find it easier to do this and your FTP number will increase.  It will then become harder but you’ll still be able to get an increase.  Eventually, you’ll have a maximal effort and from there on after, it will become impossible to get the dial to go to 12 o’clock.  The number displayed will then show your FTP and the dial becomes a fatigue gauge.

Pacing and Recovery

Unlike other tests or traditional techniques where you need to sustain your highest effort for a period of time, without any breaks, the app works differently in that it looks for how you fatigue and recover in establishing your FTP.  You don’t need to pace or worry about your intensity level.  Simply keep going until you can’t go any longer and the final number will represent your FTP.

How long do I have to ride for?  20 minutes? 1 Hour?

Although FTP is often characterized as the power you can hold for 1 hour, other methods such as the 20 minute test have been used as ways to approximate this number using the 95% rule.   Our app works differently in that it looks for the power that you should be able to sustain for a very long time.  This is often very close to your 1-hour FTP power, perhaps a few watts above or below and for all intents and purposes can be used in place of FTP.  Some say that this represents a better threshold power, and is what Xert uses.

If you are aiming to explicitly test yourself with the app, be sure to warm-up and be ready for some level of discomfort as your FTP rises towards your real FTP.  Don’t worry if you don’t get there in one shot.  It’s fine to simply keep trying until you feel you’ve done your best. Obtaining your FTP can take as little as a few minutes, so long as you are prepared to go as deep as you can and put out a true maximal effort.

Other Unique Uses

The lap button on the Garmin will reset the value back to where it began.  This isn’t necessary to obtain your regular FTP, however in some special cases doing a secondary test can be very informative.  For example, if after a 4-hour ride, you’d like to understand the effect of long-term fatigue on FTP, you can reset the value and again push to your limit and see how you’ve been affected.  You can even attempt various interventions (like trying different food or drinking protocols) to see which enables you to sustain the highest FTP.  You may also try different positions on the bike as another example.

Getting Best Results

For best results, the first time you use the app, perform a Peak Power effort (i.e. obtain your highest power possible) while you are fresh and before you attempt an exhausting effort.  Look for an opportunity to put out your highest wattage possible first and from then on you should be good to go.

Looking to track your FTP and do a whole lot more?  Register for a 30-day FREE trial of Xert

2018-01-28T11:46:24+00:00Blog Post, fitness, training|