Since, I’ve been working with power and using tests to determine my zones, a few people have asked me what it means or how it works. Now, just as a little disclaimer before we start – I am not a sports scientist and the following information, including opinions and views are based on my own experiences. I just can’t help being a bit of a nerd though…

What is FTP?

FTP stands for Functional Threshold Power and it is defined as the power (in Watts) that you can sustain for 45-60 minutes. To work out what this is, usually we would do a 20 minute test and then work out 95% of your average power for that 20 minutes – this is your FTP score.

FTP scores are a personal thing and I wouldn’t get too caught up on comparing yours with others, the real measure is your power to weight ratio (but I’ll save that for another day!). Just bare in mind though, if your FTP score is going up and your weight is going down then you will be going faster for sure.

Why should I care?

Two awesome reasons to care:

  • FTP tests are a great way to measure your improvements over time by regular testing and can help to make sure you are on the right track
  • You will be able to determine your power zones which will make your training sessions more specific

Where can I do it?

The best way to measure your FTP is to book into a sports science lab where they have all the equipment that nerds like you and I would dream of and they will be able to watch your statistics and guide you towards a true test in a true lab environment, such as the Surrey Human Performance Institute (SHPI) at Surrey Sports Park. Not only this, they will be able to run additional tests like for your Vo2 max and lactate testing.

However, it can also be beneficial to do the test at home yourself if you have a smart turbo trainer that measures power output or some form of power metre on your bike – Personally, I use my Garmin Vector pedals and my Garmin 1000 to view the output.

I like using my own pedals because the results will always be relative, so even if my pedals aren’t calibrated the same as other equipment and, for example, if they were reading low, the results would still be relative – i.e. a 10-watt gain will still be a 10-watt gain.

If I test with different equipment, it may be calibrated differently and so there is no way to tell between equipment what the true results are.

In short – it’s best to test in the same environment each time with the same equipment to ensure a more accurate result.

What do I need?  

You want to make sure you get yourself nicely set up and are fit for the test (well hydrated, well rested and have eaten at least two hours before the test).

Set out the following:

  • Bike set up on the turbo trainer
  • Sweat mat (oh yes there will be lots of it!)
  • Sweat towel
  • Water
  • Garmin or other device to read output from pedals or smart trainer
  • Fan (no, not your significant other or a team of cheerleaders, just an actual fan to keep you cool!)
  • All the windows open to keep you cool and of course so your neighbours can hear your grunts
  • Banging/motivational tunes in your ears (bit of angry Linkin Park for me!)
  • Bonus hint: Put your phone on do not disturb (Last thing you need is ya ma ringing up halfway through to ask if your in for tea!!)

The test strategy

There are many tests out there published on the scary world of the Internet, but generally it will be something like this:

  • A decent 10 minute progressive warm up, ramp up to hard effort (or Z4)
  • Easy spin for 3-5 minutes
  • High level interval sprints
  • 5 min easy spin to settle the HR back down
  • Go for your life for 20 minutes, all out as hard as you can

Now, the thing to understand is, if you have never worked with power before then you will have no idea exactly how hard to start out, because if you start out at 100% max effort I can guarantee you wont last the 20 minutes.

20 minutes is actually a long time when you are busting your balls (or lady bits) and counting down every second, so you have to make sure you go in with a strategy.

Personally, I split it into 4 x 5 minutes in my head with a power goal in mind for each 5 minutes section and I always start out as high as I think I can manage to hold. I also know that if I am feeling ‘uncomfortably comfortable’ after the first ten minutes then its time to start getting uncomfortably uncomfortable!!! Hmm….Basically you got to get stepping on the gas!

There’s no hiding from it, it will be incredibly uncomfortable and especially that last five minutes which should have you giving it everything and the last minute you should be in throwing up territory!

Now what?

Once your test is complete and you’ve managed to stay upright, you will be able to view your average power output for that 20-minute effort (unless you forgot to press start on your Garmin and just been through hell for nothing, that pain has got to be worse than the test itself!!! Touch wood, I haven’t managed it so far!).

Your FTP score is then worked out as 95% of your 20-minute average power.

Once you have your FTP score you are then able to workout your training zones, which I wont go into here, but these zones are very valuable to base your training schedule on to ensure you are doing the right type of sessions to get you on a measurable and more accurate path towards your wildest dreams and goals!


OK, so now I’ve got that nerdiness out of my system, I can stop pretending to know what I am on about and go back to trying to stay within my appropriate power zones, instead of keep busting it too hard and upsetting my coach!! 😉

I hope this helps for those who were asking and of course, questions and/or feedback are always welcome, just leave a comment below.

Now get out there and get pushing that power baby yeah!!

Peace out!

Spice x