Tracking your running metrics is important if you want to improve performance. If you don’t know how fast you’re going or how far you’re running, it can be very hard to set realistic goals for yourself.
Serious training, though, often benefits from deeper analysis that just pace and distance. Those measures don’t take into account, for example, how hilly a course is, or how hard a headwind was blowing. Serious training benefits from measuring effort as well.
For years, heart rate has been the gold standard of measuring effort for runners. Entire training plans can be built around targeting certain heart rate zones. At the same time, cyclists were shifting to measuring power output as a way to track workouts. By using a power meter, a cyclist can measure their body’s output independent of hill gradients, headwinds, drafting, and the like.
Power meters revolutionized cycling, so it was only a matter of time before runners started asking whether power could be used in running as well. Most runners will take note of their pace. But if you want to improve your performance, especially your cadence, then yes, you should be monitoring your power as well as your pace.
This is where a power meter comes in. It can not only measure your power, but it can also help improve your running form when used correctly.
You can find power meters in some new smartwatches, but also as separate devices that are compatible with many watches.
Read on to see why you should use a power meter to track your running power.
What is a power meter and how does it work?
A running power meter is a small device that attaches to your shoe. It uses an algorithm to measure how much power you’re putting out when you run. Power meters can also be built into smartwatches, so you won’t have a separate device.
People who remember their high school physics might argue with this simplification, but power is a measure of force over a period of time. It calculates the amount of work that you’re doing (force), as well as how quickly you’re doing it (velocity). Then it uses those numbers to work out your power, which is how much energy you’re putting into moving. The result is presented in watts.
It should be noted that, while watts are an objective unit of measure, what the number means is dependent on your mass. Lighter runners require fewer watts to move at the same speed. Because of this, in cycling for example, a rider’s power output is not the key stat. It’s the power-to-weight ratio that is king of performance statistics, especially on climbs. This is why pro cyclists, and elite runners, tend to be exceptionally lean. Lots of power + less weight = high performance.
What are the benefits of a power meter?
Most runners take note of their pace when they’re running. But pace can be impacted and influenced by things like the terrain you’re running on, how hot the weather is, whether there’s wind, and the elevation profile of your run.
Power isn’t affected by these outside influences. It’s all about what you are putting in. There are some benefits to knowing how much power you are putting out.
Know your average power is akin to knowing your max heart rate. All other levels of exertion can be measured off of it. Functional threshold power (aka FTP) is especially important, and its heart rate analogue is the lactate threshold. You can adjust your intensity up or down immediately when you’re running in order to meet a target wattage, or if you know you need to speed up to reach your goal.
It’s also useful for running uphill. If it’s a long hill, you can figure out the exact wattage of power you need to maintain your speed going up the hill.
Does power rely on GPS?
Power is a very responsive metric that depends on you and how you move. It doesn’t rely on GPS—as long as you’re moving, the power meter can calculate your wattage.
GPS can calculate pace by using distance and time, but power is more accurate because there’s no chance of it losing signal like GPS may do.
What are the other ways to use a power meter?
To find the right pair of shoes
Using a power meter can help you to discover which pair of shoes is best for you. If you have multiple pairs of shoes, or have the opportunity to train in different pairs of shoes, analyzing your power in each pair of shoes will give you an indication of which footwear is giving you the most power.
To be clear, though, shoes aren’t going to increase your power. Rather, some shoes are better at returning energy to your stride and increasing running efficiency. In that same way that a stiff bike frame with stiff wheels is both faster and gives a rougher ride, shoes are often balanced on comfort vs. responsiveness. A power meter can help you measure where your own balancing point might be.
You may notice that the results change depending on the terrain you run on. Some shoes might serve you very well on the road, while others might work better for trail running.
Comparing your power in different pairs of shoes can help you to choose the footwear that best aligns with your goals and will do the best job of helping you reach them.
To improve running form
Shoes can be more or less efficient, but let’s not totally blame the shoes, ok? It’s your running stride that is your own personal key to running efficiency. If your power is less than it should be, and you can’t figure out why, your running form might be slightly off. Although there are certain things that should not be compromised when it comes to form, some things can fall by the wayside.
Foot landing, arm swing, and cadence can all make a difference to your form. You may not even realize that your arm swing is reducing your power, but when you start to track your power, it’s easier to uncover smaller problems when looking for the source of lost power.
You can experiment with different ways of swinging your arms to see what works best for increasing your power. The same is true for the way your foot lands, or for how many steps you take.
To know when you’re overtraining
If your power is decreasing as you run, your body may be more fatigued than you realize.
Monitoring your power output can help you spot the signs of overtraining sooner and take the time you need to rest and recover.
Will I become faster with a power meter?
Data doesn’t speed you up. Using a power meter won’t make you a faster runner. Analyzing data and using it constructively to improve your training will make you a faster runner.
Power is a metric – and nothing more – that can help you understand where you need to improve and how to improve in those areas.
You can use the data you get to experiment with your form, intensity, and even the shoes you’re wearing. In this way, you can improve your running by using the power data.
What are common problems using power meters?
Power meters are useful tools, but there can be some problems with them. Running power meters are in their technological infancy. You can’t compare one power meter to another, in terms of accuracy. They are all quite different, which can make it difficult to choose the best one.
Also not every smartwatch is compatible with every power meter. You’ll need to make sure that the watch you use is compatible with the power meter you choose before buying one.
Which app best displays running power?
There are a number of apps that display running power as one of their metrics. However, SportTracks is the most comprehensive software, and is also very easy to use.
You can schedule your runs in advance, and it syncs with most smartwatches to record your data. Power is one of the metrics it measures, and you can even set a specific power goal for your runs. It’s the most data-packed software for tracking and planning your runs and the best choice if you specifically want to track power.
TrainingPeaks is another very popular platform, but it may not sync with all devices to draw your data.
What products have power meters?
Garmin Running Power
Garmin is one of the best-known smartwatch brands, and their products are of high quality. They brought out a power meter called Garmin Running Power, but it’s only compatible with certain models of their smartwatches.
Range of watches
Garmin’s range of smartwatches that are compatible with Running Power include:
- Forerunner 935, 945 and 645
- Fenix 5 and Fenix 6
- Chronos
Additional devices
You’ll also need one of the following sensors in order for the power sensor to work:
Once you have a compatible watch and external sensor device, you can download the Running Connect app to measure and sync your power data.
Please note: in terms of data accuracy, the above products demonstrate the struggle: chest straps used to measure the power output of your legs? It’s not a direct measurement in the same way that a cycling power meter uses physical torsion on a crank arm or pressure on a pedal to track power. Running power meters are still at the point of estimating power from other metrics. Even with the foot pod, you’re not getting a direct physical measurement.
Downside
Unfortunately, only a few Garmin watches can use the Running Power meter. It can also be a disadvantage for some people to have to wear a chest strap or foot pod as well as their watch.
There is a slight inaccuracy in the app, because it has a function that accounts for wind when you’re running. But due to the GPS, it can sometimes pick up wind from a station a few miles away from where you are, making your data inaccurate.
Stryd
The Stryd is a small pod that you attach to your shoe. It measures a large range of data as you run, and syncs with either your phone or your watch.
It’s compatible with a number of watches, including 25 different Garmins, many of the Suunto watches, and the Polar M400, M430, and V800. There’s also a Stryd app specifically for Apple watches.
The Stryd is one of the most accurate power meters. It has a wind sensor built into it, so it doesn’t rely on external data that could be inaccurate.
It is an expensive power meter, and it needs to be paired at the beginning of every run, but it’s quick to do.
RunScribe Plus
RunScribe Plus is a power system that comes with two-foot pods, one for each foot. They can last up to 16 hours on a charge, and you can mount them either on your laces or on your heels.
They track a great number of metrics other than power, including things like Ground Contact Time, Impact Force and even your pronation. You get data separately for your left and right foot, which could be helpful to identify and iron out possible muscle imbalances.
The metrics it measures from you is compared to the community average, which helps you to get an idea of how efficiently you’re running in comparison to other runners. The RunScribe Plus is compatible with Garmin devices, and you can download a dedicated app for it. It also syncs with Spartan watches and the Suunto Ambit.
The biggest downside to the RunScribe Plus is the exorbitant price. Originally priced at $250, it’s now even more expensive than that because the company is targeting B2B markets. This could make it inaccessible to many runners.
Polar
Polar has released two watches that come with built-in power meters—the Vantage V and the Grit X.
They don’t need any external sensors to track your power, and you can customize your watch face to display your power metric on the screen as you run, so you don’t have to wait until after your run to adjust it.
The power meter does require GPS in order to function. Although this will use more battery, Polar is also known for its impressive battery life so it shouldn’t be a big problem. It could be a problem when running on a treadmill, as an example, because the GPS won’t pick up any movement.
There are also not as many other metrics built-in. So this is great if you want to track just your basic metrics as well as your power.
Coros Pace 2
The Coros is known for being a very lightweight GPS watch—just 1 ounce—and also for being surprisingly affordable.
But did you know that every one of their sports watches comes with a built-in power meter? The Pace 2 was the original power meter watch, but they’ve since integrated it into every other watch of theirs.
The Coros is fully compatible with a Stryd foot pod, and will measure every metric, not just power. The downside is that, although they have a mobile app, they don’t offer a web-based platform for tracking and planning. But the Coros is fully compatible with SportTracks, so you can use that easily.