Power Meter Guide: How to Pace with a Power Meter

It's one thing owning a power meter, it's another setting it up and using it to improve your performance. In the latest in the Feel the Power series, Nik Cook explains how to set up the head unit, and use it for pacing in longer rides.

Having found your FTP and set your power training / pacing zones based on it, it’s now time to apply those zones to your riding. If this first sentence makes no sense and you have no idea of what an FTP is, check out my first three articles to fill in the blanks.

We’re going to keep the practical side of pacing with power super simple and focus on longer endurance style rides. This could be a sportive / gran fondo or your long weekend training ride.

Setting up your head unit

The first thing to do is to ensure that you’re looking at the right data fields on your head unit. I know that some riders love to see every data field available to them but, when I’m riding, I like things to be simple and prioritise these seven fields.

3-second average power

This should be your big top-line data field. You don’t want to see instantaneous power as that will jump around too much but a 3-second average gives a stable enough figure to adjust to and pace from.

FEEL THE POWER 1: Why a Power Meter Should Be Your First Cycling Upgrade

If you’re on a pancake flat course or a long fairly even gradient climb - such as you might find in the Alps, you could maybe opt for 5-second average power for more stability. 


Power Zone


I’ll only tend to have this one showing if my FTP / zones have changed recently as, once you’ve been riding with a power meter for a while, you’ll have them dialled into your memory.

Cadence


Always good to know how fast (or slow) those legs are spinning.

Heart rate


As I mentioned in my first article, just because you now own a power meter, it doesn’t mean that you should ditch your heart rate monitor. A power meter tells you what your body is outputting. A heart rate monitor tells you the effect that that effort, and a number of other factors, is having on your body. If your power zones are set using FTP and your heart rate zones from your Functional Threshold Heart Rate (FTHR) from the same test, most of the time when you’re riding, they should pretty much tally. If not, it usually indicates that something - the impact of altitude, temperature, poor pacing / fuelling / hydration, overtraining etc etc is having an effect and needs to be accounted for. For example, I did a ride from sea level to the summit of Mount Teide at 7,217 feet / 2,200m over a 27 mile / 45km climb. Once I got above 5,577 feet / 1,700m, for Zone 2 power, I was starting to tickle Zone 4 heart rate. This wouldn’t have been sustainable for the rest of the climb so I had to back off based on what my heart rate monitor was telling me rather than slavishly sticking to my power numbers.

Heart rate Zone 


As with Power Zone, once you’ve been riding for a while with heart rate, you’ll know you zones and can ditch this data field.

Workout time

I’ll tend to use this, as much as anything, to cue eating and drinking. My tried and tested is a good sip on my bottle every five minutes and a snack every 20-30 minutes right from the start of any long ride. 


FEEL THE POWER 2: The Watts, Whys and Hows of Functional Threshold Power (FTP)

Distance

Not essential but it’s nice to know how far you’ve ridden and how far there is to go.

If I haven’t got Power Zone and Heart rate Zone showing, I’ll tend to have Total Ascent - again, nice to know how much I’ve climbed and how much is left and Time of Day - so I’m not late for lunch.

Why not speed / average speed?


Many riders tend to judge a ride and their progress based on average speed but it’s really a pretty meaningless metric. The problem with speed is that it’s impacted by far too many external variables.

Take two rides on consecutive days and, even on the same loop as you rode the day before you’ve got a variety of factors to consider: temperature, air pressure, wind speed / direction, tyre pressure, different kit, your mate putting in a longer and stronger pull etc etc. This is before you even factor in other road users - slowing you down or, with an overtaking car, sometimes giving you a bit of a speed boost. There’s just no way you can compare average speed of different rides. 

If you doubt the impact of these variables, look at when Sir Bradley Wiggins set his hour record mark of 33.8 miles / 54.526km at Lee Valley VeloPark in 2015 in the incredibly controlled conditions of an indoor velodrome. The air pressure during his attempt was particularly high and it has been calculated that that variable alone cost him at least 1,640 feet / 500m!

Pacing a sportive / gran fondo or any endurance focussed ride with power

If you’ve blown-up on a climb, had stomach issues, suffered from cramp or simply run out of steam on a long training ride or a sportive / gran fondo, it’s more than likely that poor pacing, assuming you were trained for the ride, probably played a significant role.
 
One of the biggest advantages of a power meter, especially for less experienced riders, is that it provides an objective, simple and highly effective tool for pacing.
 
A power meter effectively allows you to “flatten” any ride, no matter how mountainous, so that your effort will be more even overall.

FEEL THE POWER 3: Know your Training Zones & How They Should Feel

Based on the zones that we discussed in the previous article, the simple pacing rules of thumb for long rides are:

• Flats: Zones 1-2 ideally sat in a group

• Descents: Zone 1 or freewheeling

• Sustained climbs: Zones 3-4

Sticking to these guidelines will effectively average out the ride into Zone 2 which should be sustainable. It’s really important that even if early climbs feel easy at this intensity that you stick with it.
 
On steep climbs, it might well be impossible to keep your power down and keep moving but you should limit spikes into high Zone 4 and Zone 5 as much as possible. Imagine you’ve got a limited box of matches and every time you push into Zone 4 or higher, you burn one. Run out of matches and you’ll come to a grinding halt.

In my next article, we’ll look at the key power metrics you’ll see when you upload a ride to Strava and what they mean.