Heather Fell: Do you associate power meters with professionals, something that you only
need if you're racing or taking your training really seriously? Well, yes. Professionals do
use power meters, but there's still a lot that all of us can gain from using them,
no matter what level your cycling is at. Mark Threlfall: Exactly. In which case,
it is about time we cover the benefits of the power meter and how you can use one to improve
your own cycling. [music]
Heather Fell: A power meter gives you that additional metric, your wattage,
the amount of power that you are putting down through your cranks and it's instantaneous. As
soon as you put down more power, the number will increase. As soon as you ease up, the number will
back off. This is the most significant difference between heart rate and power, and one of the main
advantages. Having this instant feedback allows you to accurately measure your effort. It's black
and white. The numbers don't lie, although, do just make sure your power meter is calibrated.
The other two common measurements, heart rate and speed, can be affected by so many factors. Speed
being the most obvious. You've got headwinds versus tailwinds, downhill compared to uphill,
drafting or riding solo, the road surface, your position on the bike. I could go on trying to
compare your output day-to-day, even on the same stretch of road, is pretty unreliable.
Then, heart rate has more subtle limitations,
but there's the problem with the lag that I've already mentioned. As you increase your effort,
your heart rate isn't going to increase until sometime after. On top of that, there's some
other things that can affect your heart rates such as dehydration, caffeine, and even fatigue.
[music] Mark Threlfall:
Now, the benefits of the power meter actually go far beyond simply this accurate and real-time
feedback that they provide. It's also what you do with these numbers that can really make the
difference. Now, if you're new to using a power meter, I'd actually suggest you just
head out as you normally do on your rides and start to observe the numbers that it starts to
produce for you. With time, you'll start to learn what's normal for you and how it
changes with different efforts. As you do start to become more accustomed to it, you can maybe start
including some structured workouts in which you use power. To do this, you're probably going to
want to know your functional threshold power. There's a number of ways you can find
this number out. The most common is doing the 20 minute FTP test, where you ride as hard as he can
for 20 minutes, you monitor and you record your power data, and then you take 95% of that average
power, and that is your FTP. If you want to find out more on that, we do have videos over on GTN
which explain it in detail. You can find those in the description down below. Now, I should actually
point out that most people find a difference in their power output when riding indoors
versus outdoors. Typically, most people find that they can put more power when riding outdoors.
If you have done your FTP test indoors but you are doing a majority of your training outdoors,
then it's worth bearing that in mind, and obviously vice versa.
The same goes for hills. A lot of people find they can put out more power on hills. I would always
advise you to try and find a nice flat section to do your FTP test on if you are doing it outside.
Hopefully, by this point, you're thinking, "Yes, a power meter is worth investing in,
but should I go for pedal-based, a crank-based, a hub-based, single-sided, dual-sided?" There are so
many options out there. It's a total minefield. Fortunately, again, we've got a video on that
which goes into some comprehensive detail. I'll link that in the description just down below.
[music] Heather Fell:
Power isn't measured in watts. That part is straightforward. Like I said, it's instantaneous.
It gives you that feedback straight away, but that comes with a slight problem. Even the most
professional cyclists are not going to be able to maintain a very constant power all the time.
As a result, you'd see numbers constantly flicking and changing, which are not only hard to read, but
also quite hard to interpret. You've got a couple of options. You can use average power, which would
obviously give you average power throughout the whole ride. This can work quite well if you're,
say, doing intervals and you're using the lap function on your bike computer
and you ride to that average power. There's another option because that
doesn't work so well if you're, say, riding on a long ride in a group or you're on uneven terrain.
This is where the three-second power window comes in quite handy,
and most bike computers will give you that option. It basically gives you your average
over this three-second period. It will change, but not so dramatically,
and it's much easier to pace your effort off. There's one other version, normalized power.
This is a calculation of your power taking into account the conditions. As a result, it can give
you a more realistic number and you'll be pleased to hear if you're riding on hilly roads or varying
your effort, it often actually comes out higher than the number that your average power shows.
If you're lucky enough to have a dual-sided power meter, then you can have the display for your left
and your right crank or pedal. That's quite interesting to see if you've
got any imbalances and really focus on just making a nice even pedal stroke.
[music] Mark Threlfall:
Well, that covers the obvious benefits. With a bit of time consistency using power,
you will start to learn how to use this metric to notice and tweak some of the smaller things. For
instance, if you are still using heart rate, then you may be able to start to correlate
your effort and your power with your heart rate. That may allow you to notice things
like the early onset of fatigue and over-training or on a more note, improvements in your fitness.
Heather Fell: Then, you've also got the option of playing around with aerodynamics. Say,
you have got a relatively flat section somewhere without too much wind, or you can simply ride that
set distance at a set speed and measure your power output on it. Then, make some changes, whether
that's to your position or something to your bike or accessories. Ride it again at the same speed
and see if your power's changed. If your power numbers have dropped off, then that's a pretty
good sign that you've improved your aerodynamics. Mark Threlfall: I've got to say that is something
I have personally really enjoyed with power over the time when I have had time to do that. Also,
things like your cadence. Increasing, reducing your cadence, and seeing how my power is affected
by that, and if I can keep the power the same. As you've mentioned with your aerodynamics,
tweaking my position, what's the difference between my power up when I'm on the drops
versus in the clip-on aero bars when I drop my position lower? It's really, really fascinating.
You can start to build this bigger picture and make yourself essentially a more efficient rider.
Heather Fell: There is so much out that you can do to experiment. It is really interesting.
Mark Threlfall: Yes. Well, as you have probably seen, this is a very big topic. If you do have
any questions, please do drop them in the comment section down below. We hope you guys have enjoyed
this video. If so, please do give it a like. Don't forget to give us a follow over on social media
and subscribe just down below. [00:07:18] [END OF AUDIO]