What the FTP?!

24th February

If you’ve ever set foot in a spin class at Gymbox, there’s a good chance you’ll know this week’s guest blogger on a fairly intimate level. She’s probably sent you on a glute-screaming hill climb. Tested the limits of your lung capacity on that cheeky final sprint. Even got you popping the odd press up to Little Mix. But today, Cycle Club Master Trainer Jenny Lawford is here to share her wisdom on all things FTP. Sure, you might not have a clue what that even means right now. But by the end of this you’re going to understand why those three letters hold the secret to kicking your cycle training up a few gears. No… watts. Oh, just read it will you?

Cyclists love an acronym - IF, TSS, W/KG…. the list goes on. But perhaps the one you’ve heard in class (and not had a clue what it stands for) is FTP. Your Functional Threshold Power. Clear as mud? Let me explain.

Your FTP is the maximum average watts you could sustain for an hour, and is a metric cyclists use to measure improvement - the higher your FTP, the more power you can put on the bike. Power refers to your rate of work and is the combination of Torque (amount of force on the pedal) and Cadence (the speed at which you are riding, or RPM). I know, headache already.

Simply put:

Power = Resistance x Speed.

How hard you are working to turn those pedals and how fast you are doing it.

Ideally we are looking to increase your power threshold, be it by next week or next year. The number itself is irrelevant, so no need to sneak a look at your classmate’s screen. The highest FTP in the studio doesn’t necessarily belong to the strongest member. That prize goes to the person with the highest power to weight ratio, or watts/kg. Basically - how much power you can put out in relation to your size. But how on earth do we know what your FTP is in the first place? And how do we apply it in class?

All classes at Gymbox use the Power Training mode on the IC7 bikes which handily use a combination of your gender and fitness level to give you an estimated FTP. This is a great place to start if you haven’t yet done a test and your instructor will be able to look at your stats at the end of class and advise you on whether your threshold needs adjusting. Once you start getting in to your indoor cycling (which you will, trust us - this stuff is addictive) you’re going to want to know exactly what your threshold power is and this can be found out by doing an FTP test.

There are numerous ways to test this, the golden standard being the full hour but even for cyclists this isn’t practical (not to mention absolutely hellish!). Instead, the bikes we use at Gymbox, offer two tests which are built into the console - a ramp test (which adds 25 watts every 4 minutes) and a 5 minute test where you perform at max effort between 80-100rpm, to which the bike unkindly subtracts 15% from your average power to make up for the fact you didn’t do the full hour shebang. In both tests, you’re looking to keep the green light ON.

You caaaaan do these tests on your own but seriously, you’re gonna want some encouragement and banging beats to sustain an all-out maximum effort (plus the instructor can give you guidelines on what’s a realistic max average wattage for you to work at). And this is where Cycle Connect comes in...

Connect is our performance-based class, which has an 8-week rotation programme where you will test on the first week and spend the next 7 weeks working on all areas of your fitness and technique in order to improve for the next one. All of your data is collated and displayed on a screen, where you work as a group as well as the occasional team battle or power leaderboard (great for you competitive folk but don’t worry, it’s a small part of the class and completely anonymous!). Our main focus is getting you fitter, stronger and most importantly POWERFUL!

Once you know your FTP, the bike will then be able to work out exactly how much power you need to put out to hit specific training zones which it translates into colours. And from this, you’ll be able to follow a class plan created by your coach, which means that the most inexperienced cyclist can ride next to a triathlete and both get a tailored workout - be it Bike & Beats, Connect or Cyclone! Cool, huh?

Here is a basic summary of the zones, the corresponding colours and how you can expect it to feel in Layman’s Terms.

Zone 1 (white)

Active recovery (pretty easy, if only it was like this for the whole class)

<55% of FTP

Zone 2 (blue)

Endurance (ok, getting a bit trickier now but I’m still OK)

56–75% of FTP

Zone 3 (green)

Tempo (OK here we go, starting to get a bit of a sweat on but I can still just about talk and could do this for a while)

76–90% of FTP

Zone 4 (yellow)

Threshold (Wow. Not in Kansas anymore. This is starting to get uncomfortable - OUCH!)

91–105% of FTP

This is where your actual FTP lives!

Zone 5 (red)

VO2 Max (Oh my word - this is HARD!)

106–120% of FTP

Zone 6

(red - with a ring of fire)

Anaerobic capacity (I really can’t do this much longer, it’s super uncomfortable!)

121+% of FTP

Zone 7

(red with a cyclone effect on the screen)

Neuromuscular power (Crikey! This is everything I have - and that’s it, I’m spent!)

150% plus of FTP

The instructor will have carefully planned the intensity of the class, so always try and stay within the correct colour zones as much as you can. If it feels too easy or hard, be sure to let them know at the end of the session and they’ll be able give you some guidance on what to do next time.

Hopefully that’s cleared up some of the jargon and pieced together a few bits of the puzzle. Pop along to Connect during test week (the next round is week commencing 4th March) to determine your FTP, which you can then apply to any of our spin classes, Then, in 8 weeks’ time, you can try again and see how much you’ve improved. As always, if you have any questions at all, be sure to ask your instructor. They’re there to help!

You can follow Jenny on Instagram

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