A Functional Threshold Power (FTP) cycling test is a simple, non-invasive, way of assessing your cycling performance level. As well as measuring cycling performance, it’s widely used to determine specific cycling training zones.
In this article we’re going to take a look at FTP tests, how to assess FTP and look at ways to improve your cycling FTP.
What is an FTP cycling test?
Simply put, FTP represents the highest average power (measured in watts) you can sustain for one hour of continuous cycling. An FTP cycling test is used to measure or estimate your FTP
Is the FTP the same as the lactate threshold?
Often, the term FTP is used interchangeably with lactate threshold. However, whilst both FTP and lactate threshold occur at similar intensities, they are not the same.
The lactate threshold represents a physiological change (a specific rise in blood lactate), whereas FTP is best described as a performance measure – the amount of power sustainable for 1 hour.
The confusion occurs because on average the lactate threshold (LT) occurs at an intensity that can be sustained for around one hour. However, there can be wide individual variation – for one athlete LT might be at an intensity sustainable for 50minutes, for another athlete it could be 70minute intensity.
So, FTP and LT don’t necessarily occur at the same intensity. And, depending on the individual athlete, their FTP might be higher or lower than their lactate threshold.
Why use a cycling FTP test?
Firstly, FTP is one of the most accessible and effective performance measures for endurance cyclists. It’s also relatively straightforward to test – all you need is a bike, a way to measure power (power meter, turbo trainer, training software, Smart bike etc) and the willingness to push yourself, to your limit.
As well as assessing current performance levels, FTP tests can be used to prescribe training intensities. And, once you know your FTP, you can then repeat the test to assess the effectiveness of your current cycling training program and track training progression.
Once you know your FTP you can assess this in two ways:
- Absolute value – for example an FTP of 380w
- Relative value – it can also be expressed in relation to your bodyweight (for example 380w/67kg = 5.67w/kg).
In this way, we can assess improvements/changes in absolute power and at the same time, take into account changes in bodyweight.
How to measure your cycling FTP?
What equipment’s required? Either, a bike fitted with a cycling power meter, a turbo trainer capable of measuring power, software (like trainerRoad) capable of estimating power, or a Smart bike, and a heart rate monitor to record heart rate during the test.
Considerations and precautions before testing: The test itself, is a prolonged high intensity cycling test, completed at an intensity just below VO2max. As such, it’s important to have a good basic fitness level and training experience. You should be injury free and free from any serious underlying health conditions before attempting any FTP test.
FTP cycling pre-test procedure:
Prior to testing ensure that your power meter, or trainer, is calibrated (if required).
Include a good warm up: Ideally for around 15 minutes – this should include a series of short accelerations that go above expected FTP power.
Different types of FTP cycling tests:
To assess/estimate FTP itself, we have a few different options:
#1 60-minute FTP test
The 60-minute cycling test, involves riding as hard as possible for 60minutes, whilst recording power and heart rate.
The average power sustained across the 60minutes is then used as the measure of your FTP.
Whilst, this is often considered the most accurate; it’s extremely difficult to maintain your highest average power for 60minutes, especially in a non-competitive situation – for most athletes, this just isn’t realistic.
Even if you’re highly motivated, this will be difficult to maintain, and you’ll likely record a lower average power than you could sustain during a competitive situation.
A more practical option for most cyclists, is either to complete a 20-minute, or, an 8-minute test.
#2 20-minute FTP test
As with the 60minute test this is all about average power – cycle as hard as you can for 20minutes, whilst recording your power and heart rate.
The average power from the 20-minute test, can then be used to estimate your FTP. To do this, we simply multiply the average power for the 20minutes by 0.95.
Whilst, this test sounds straightforward, it’s mentally challenging – especially when you’re counting down the minutes! So, there’s no point doing the test if you’re not sufficiently rested, and well-motivated.
Another, alternative is an 8minute test.
#3 2 x 8minute combined VO2max and FTP cycling test
The 2 x 8-minute test is another straightforward option for estimating FTP.
An advantage with this test, is that we can also use this to gain an estimation of power at VO2max. So, this one test gives a measure of power at both VO2max and FTP. But, remember – this is just an estimation of your power at VO2max. Since, we’re not testing VO2max itself, we can’t be certain that this power correlates with your VO2max.
As the intensity of this test is slightly higher – the first 8minute interval is at around VO2max intensity – we need to ensure that we include a thorough warm up.
So, how does this test differ from the 20-minute FTP tests? There’s, two main differences:
- Firstly, the intensity is higher.
- Secondly, the test involves completing two intervals rather than just one – 2x ‘maximal’ 8-minute tests, separated by 10 minutes of easy cycling.
The results from this test, can then be used to estimate FTP and VO2max power.
How to complete the 2 x 8minute test:
- Following a good warm-up, complete the first 8-minute interval at the highest power/effort level that you can sustain. Try not to think about the second interval, just focus on maintaining the highest sustainable power for the first 8 minutes.
- Once completed, cycle at an easy intensity for 10minutes.
- Then, complete a second 8-minute interval, again at the highest power you can sustain. Expect your average power to be down by a few percent during the second 8-minute test. As an example in my recent test my power was 3.5% lower for the 2nd 8-minute interval.
How to interpret the 8minute test data
The average power from the first 8-minute interval, gives us a measure of the power at VO2max. This can then be used for setting power targets for VO2max cycling intervals.
To estimate FTP from this test, we simply average the power from the first and the second 8-minute intervals and then multiply this by 0.9.
So, how does this compare with the 20minute test? My experience shows this to be highly comparable to predicted FTP from the 20-minute test.
When I recently completed the 2 x 8min test, my predicted FTP was within 0.5w of the estimate from the 20min test. So, for me the 2 x 8minute test is a useful alternative.
One further option is a ramp test, or maximal aerobic power (MAP) test.
#4 Ramp/Maximal Aerobic Power Test (MAP)
The ramp test can be a useful alternative; that’s slightly less stressful and easier to complete for most cyclists. It differs from the earlier tests in that this follows an incremental protocol – the workrate increases in increments throughout the test, until you are no longer able to complete a work stage.
How to complete a RAMP test
- Firstly, RAMP tests are built into many online programs like TrainerRoad, Zwift and the WattbikeHub; making testing much more straightforward if you have access to these.
- During the test, work rate will increase in 1minute increments – normally starting at a fairly low/easy intensity.
- Workrate is typically increased by 15-25w per increment (depending on fitness/conditioning and gender)
- Continue until you are no longer able to maintain the target power.
- Average power over the final minute is used to calculate VO2max and FTP
Interpreting the RAMP test:
If you’re using a training program, then this will automatically calculate FTP and VO2max.
FTP is normally calculated as being 75% of maximal aerobic power (MAP); with MAP being the average power over the final minute of the test.
There’s one downside to using a RAMP test for FTP estimation: FTP doesn’t fall at the same percentage of MAP for every cyclist. For some it might be 72-75%, for others it’s nearer to 80%, and for some it’s above 80%.
It largely depends on whether your strengths fall more on the endurance or sprint end of the spectrum. Typically, if you have a very high level of aerobic endurance, then your FTP will be at a higher percentage of MAP. So, this test can be less accurate if you don’t know what percentage of MAP equates with your FTP.
How to use your FTP cycling test results to set training zones:
Once you have your FTP test data you can then use this to establish your training zones; based around percentages of FTP power and heart rate.
If you’re using training analysis software like TrainingPeaks, FinalSurge, Strava, or, training programs, like Zwift, TrainerRoad, and Sufferfest; then these can automatically calculate training zones based on your test result.
These zones can then be used to set power targets for your training rides, intervals and recovery rides.
Below are the most commonly used training zones, originally proposed by Allen Hunter and Andy Coggan in their book Training and Racing with a Power Meter.
|Zone||Purpose||%FTP||% FTP HR||RPE||Effort sustainable for*|
*Approximate values, which are highly individual.
These give a good basic framework. One downside here is the wide power range for each zone. Another factor is: heart rates don’t always match with corresponding power zones.
Fine tune your training zones for more effective training
If you have a coach, then they will most likely look to narrow the range of these zones; making these more specific to you, and your own training/racing targets.
With the exception of the endurance and recovery zone, I prefer to narrow these zones down to a 5-8% range.
Here, the 2 x 8minute test can be useful as it allows you to be more specific with your VO2max power zone. From the 2 x 8minute test the average for my first 8minutes, was ~113% of FTP, allowing me to refine the VO2max power zone from 106-120% of FTP, to a 5% range of ~113-118%FTP.
Having said that, it’s important to remember, that just like FTP testing, this provides an estimate, and it’s not actually measuring VO2max.
How to improve your cycling FTP
If you can measure it, you can improve it – and your FTP is no different!
Simply put, specific targeted training will improve your FTP. And there’s a number of different approaches that will all help to raise your FTP.
The traditional approach is to focus on endurance miles, combined with specific intervals completed at close to FTP. Normally, this involves longer intervals, such as the classic 2 x 20’ completed at close to FTP.
However, the best long-term approach is to use a range of training intensities – some above, some below and some at close to FTP intensity – or lactate threshold (if you’re using a lab based test).
Ideally, you’ll want to be including:
- A significant amount of low intensity endurance training to build your aerobic base
- Tempo, lactate threshold or supra-threshold intervals, to improve your ability to sustain a higher percentage of VO2max
- VO2max intervals to develop top end aerobic fitness and efficiency
- Supramaximal intervals to improve neuromuscular co-ordination and peak power
- Strength training to develop strength, power and efficiency
Training specificity is important
In terms of specificity, training slightly above your FTP intensity is actually more specific for improving your FTP score than training at your FTP!
If that sounds counterintuitive, think about how most cyclists assess their FTP – through a 20minute maximal test. Not, through a cycling test at FTP intensity.
In this way, training at FTP will help to improve your FTP, but it’s actually less specific for improving 20-minute power – which is what your testing during a 20minute test.
So, if you’re using the 20minute test to assess FTP, and you really want to improve your FTP score; the best approach is to be specific, and train at close to your maximum 20-minute power.
Not only, will training at that intensity better prepare you physically, but you will be mentally more prepared. Specifically, you’ll be more accustomed and more comfortable at that intensity.
Whilst, I’m not advocating training just to improve a test score; I’ve seen real benefits from training just above the intensity of FTP (specifically supra-threshold intensity), on race performances. This can really benefit endurance cycling across a range of events. But, it’s especially beneficial for events lasting from ~15-60minutes.
How often should you test your FTP?
If your highly competitive (either with yourself, or against others), then it can be tempting to overuse FTP tests. However, that’s not going to make you a faster cyclists – well, not in the long run – we need to use these tests sparingly and appropriately.
So, what’s a good frequency for FTP testing? Firstly, they’re challenging tests – both physically and mentally – and to get the best from these we don’t want to overuse them.
Secondly, if we think purely in terms of training adaptation; any change to training (especially if you’re well trained), normally takes a minimum of 4-6 weeks to have a noticeable effect. In view of this, there’s really no need to include FTP tests any more frequently than every 4-6 weeks.
My preference is to use these infrequently – ideally with around a 6-8-week gap between tests. So, unless you’re relatively new to training, or there’s been an obvious jump in fitness, 6-8 weeks is a good frequency for most cyclists.