FTP Testing - Coggan or Friel? Is the 5% discount too much?

Dr. Justin Choo on the Dragon's ITT course, North Lantau

Functional Threshold Power (FTP) is defined as the average power that you can maintain on the bike for a one-hour, all out, race effort.

Knowing your FTP allows you to set zones that form the basis for your training. There are many different protocols used to test for FTP. Two of the most widely used methods are the Coggan test, and the Friel test.

Presented in his book Training and Racing with a Power Meter (widely considered to be the power training bible), the Coggan Protocol is essentially as follows:

1. 20 minutes easy warm up 
2. 3 x 1-minute wind ups with a minute rest between (100 RPM pedal cadence)
3. 5 minutes easy
4. 5 minutes all out (hard at first, but not so hard that you can't complete the effort)
5. 10 minutes easy
6. 20-minute time trial effort (this is the test - like the previous 5-minute all out effort, keep in control, hard but steady, you don't want to over cook it and die at the end)
7. 10 to 15 minute cool down

You then take your average power over the 20-minute hard effort, and subract 5% to get an estimate of your FTP.

Another popular and much simpler test is what I've always referred to as the Friel Protocol. It is:

1. Warm up
2. 30-minute time trial (this is the test) all by yourself (no training partners and not in a race - it should be done as if it was a race for the entire 30 minutes)
3. 10 minutes into the test click the lap button on your heart rate / GPS device 
4. When done look to see what your average heart rate was for the last 20 minutes - that number is an approximation of your Lactate Threshhold Heart Rate (LTHR)
5. When done, look to see what your average power was for the entire 30 minutes - that number is an approximation of your FTP

It is elegant in that it yields an FTP in 30 minutes with no correction. And in the same test you also get you get a nice LTHR estimate from the last 20 minutes, and again no correction is applied. Essentially you are chopping off the first 10 minutes in which the heart rate climbs more rapidly up to homeostasis, and then settles to climb more gradually around the LTHR, around the last 20 minutes (see pic below, with the initial heart rate ramp up highlighted).

FTP Test, with initial heart rate ramp up highlighted

The main differences between Friel and Coggan then are:

• Duration of test - the Friel test uses average power over 30-minutes, the Coggan test over 20-minutes.
• Discount to calculate FTP - the Coggan average power is discounted by 5%, there is no correction on the Friel test.
• Warm up - the Coggan method tires you out with a hard warm up, the Friel warm up is easier (but the test is longer).

Friel has argued that no correction is needed because when you do a test alone, you feel sorry for yourself, and without the adrenaline of a race situation to push you, you simply can't push yourself hard enough.

And I totally agree with him!

I propose that the 5% correction factor is excessive for most non-elite athletes.  Age group athletes just don't have the chronic tolerance for pain that elite and professional athletes do. These people, as part of their job, need to habitually push themselves to levels that they race at. The have formed a mental discipline and self-knowledge that allows them to dig deep and simulate a race situation within themselves. Psychologist and researcher Sian Beilock describes this ability well in her book Choke. Being able to simulate a race situation in your head, visualize all the accouterments of the competitive atmosphere, and then be able to push your body to suffer as though you were in it, is a honed skill. And it's a skill that pro and elite athletes usually possess, but that many age groupers do not!

Thus, I think the 5% correction is excessive for non-elite athletes, and a better estimate of FTP for age groupers is the Friel estimate, or the Coggan estimate, with the hard warm up but without the 5% reduction.

I've seen this for my own performances and those of nearly all my power meter customers. The long race time trials yield 1-hour average power levels within 1-2 watts of the predicted ones without correction. And I suspect this would be the case for most age groupers. I can back this up with numerous race time trial results and step test lab test results from the Institute of Human Performance at HKU from me and my customers!

FTP ramp test at HKU

One very negative repercussion of this then is that if we are discounting the FTP test number by 5%, then we are setting our training zones too low, and thus not getting the full effect that we should be getting from our training.

So with that I was surprised while reading Joe Friel's latest book, Fast After 50, that the FTP test he is now recommending is the Coggan test and not the 30 min test that most of us refer to as the "Friel" test!  In all his previous books (there are many!) and on his blog, he has always advocated the 30-minute test. So I asked him in an email about the change. His reply:

Hi Tony, 

Thanks for your note.  Good insights. I have used both methods (and more) but the Coggan 20-min test has become the standard, it seems. Do whatever works best for you and your clients. There is no right or wrong here. I also tell coaches to trust themselves when it comes to making an opinionated change in FTP based on recent training data. FTP changes a bit on a daily basis due to fatigue and other lifestyle factors not to mention psychological variables also. It even changes during a ride. Weather can affect it. So there are many variables. What we are aiming for is to get a ballpark number—albeit a small ballpark.

Good luck! 

Fair enough. I could find no research to validate the use of the 5% Coggan discount, and none that considers that it might be different for non-elite athletes.

So until I find some validation, I won't be discounting my own FTP test numbers when setting my power training zones, and I don't recommend that my customers do either, unless, that is, they are elite athletes.

A Sweet Spot Protocol for Hong Kong

The members of the Lantau Buffalos Team Time Trial team are in a heated internal competition, as we had a few more riders than slots for the HKCA race.  We are using the TC10 course just outside Discovery Bay, Hong Kong, to chose the team.  Since this is a great basic test of fitness, the results can also be used to come up with a sweet spot for training for steady state events.  I've drafted the below and copied here in case anyone else might benefit from it.

HOW TO FIND YOUR SWEET SPOT FOR TRI AND TT TRAINING

Based on Friel Heart Rate Zones

Go out and do a test on the 16k TC10 course or any flat, 10 mile (16 km) course.

• 20 minutes easy warm up
• 3 x 1-minute wind ups with a minute rest between (100 RPM pedal cadence)
• 5 minutes easy
• 5 minutes all out (hard at first, but not so hard that you can't complete the effort)
• 10 minutes easy
•  25-30 minute time trial effort (like the previous 5-minute all out effort, keep in control, hard but steady, you don't want to over cook it and die at the end - INSERT YOUR 10 MILE COURSE HERE)
• 10 to 15 minute cool down

Then, take the average heart rate over the last 20 minutes of the TC10 course (you can just eyeball the plot in Strava or Garmin Connect, or if more precision is necessary use a program like SportTracks or Training Peaks to insert a lap at the finish time minus 20 minutes). This number is your Lactate Threshold Heart Rate (LTHR).

Heart Rate Zones:

Then, use the factors below (from this link) to determine your HR zones.

Bike Zones

Zone 1 Less than 81% of LTHR 

Zone 2 81% to 89% of LTHR   

Zone 3 90% to 93% of LTHR   

Zone 4 94% to 99% of LTHR 

Zone 5a 100% to 102% of LTHR 

Zone 5b 103% to 106% of LTHR 

Zone 5c More than 106% of LTHR

More on HR training use the Friel zones can be found here, here, and here.

Sweet Spot:

The Sweet Spot for steady state racing (like triathlons and time trials, as opposed to road races, sprinting, etc.) is 95% of LTHR, plus or minus 5%.  So, for example, if my 20min average is 154bpm.  My sweet spot is 154 x 0.95 = 146, or a range of around 138-154bpm. Note that this corresponds to Friel's zones 3 and 4.

If you are training by power, use the average power over the ENTIRE TC10 test (not just the last 20min).  This is your Functional Threshold Power.  Your power "Sweet Spot" is at 90% of the FTP plus/minus 5%

The advantages of doing this test yourself over a set course and distance is that you are more likely to push yourself harder if it's a fixed distance, plus you might get some bragging rights on Strava!  You don't have to pay a lab to get the numbers, and it's easy to repeat and check your progress over time.  Note that your LTHR won't change much, but your power will increase and time decrease with training.

I don't  recommend any method that uses the 220-AGE formula  to determine heart rate training zones.  The 220-AGE formula has been completely discredited, and just from polling my own small network of bike fit customers, friends, and team mates, doesn't account for the very large range of variability of people's heart rates at threshold, which seems to have little correlation to age.