Runners looking to gain an extra edge over the competition now have more ways than ever to do so - and one of the buzziest metrics gaining momentum over the last few years is running power.
With running watches, clip-on meters and other wearables churning out more stats than ever, it can be difficult to know which ones to focus on during your training.
Essential reading: Your running watch explained
And while most runners have a base understanding of something like heart rate or pace, running power isn't as immediately intuitive. Like every activity tracking metric, it's also not for everyone.
For those intrigued to see what running power is and how it can make a difference to their runs, training and race performance, however, we've done our best to explain everything you need to know about running with power.
What is running power?
If you're into your cycling, then you may well be familiar with the concept of power as a metric and power meters to gauge this. The core principle is the same with running power, only you'll have on-shoe wearables, running watches and other devices doing the processing.
Essentially, running power focuses on measuring work rate or performance in order to offer insights into fitness levels and the effectiveness of your training, and is shown in watts.
When it comes to running specifically, though, things are a little different from cycling.
For this, we're going to refer to the book Run With Power by elite coach Jim Vance to give us an answer to that question. Vance has coached a number of amateur and elite runners and is the founder and team director of Formula Endurance, a USA Triathlon High Performance Team.
In response to the question of what running power is, this is what Vance had to say:
"In its simplest terms, Power is work rate: It's the measurement of how much work you are doing and the rate of speed (how fast) you are doing it. You already have an innate sense of what power means from your training: you know, for example, that the faster you run over a given distance, the greater your power output must be to accomplish the work generating speed."
Vance says that power is the measurement of how much work you are doing and the rate of speed (how fast) at which you are doing it.
He also refers a lot to formulas, which look like they are straight out of an algebra textbook. Ultimately, this is just another way for runners to measure performance.
The benefits of running power
Simply, the aim is to get you running better and help you make the most of your training. Analyzing running power alongside metrics like vertical oscillation and cadence should, in theory, help users achieve faster times, improve pacing during races and enhance their form.
The folks at Stryd, one of the most popular footpods, put this metric for runners into the context of race terms. They talk about the idea of following a targeted power number at the beginning of a race and sticking with that number to nail your personal best.
It feels like a metric that is built for the elite and serious runners, but, with more and more companies beginning to offer their proprietary takes on the metric over the last few years, it'll no doubt begin to find some fans lower down the running food chain.
The kit you need to run with power
Unlike cycling, options aren't as widespread just yet, but things have improved greatly since we first started writing about the metric around five years ago.
One of the most popular comes courtesy of Stryd, whose footpod sensor clips onto your laces and delivers rich running analytics and power estimates.
Using various motion sensors packed into the footpod, Stryd's setup is able to record metrics indoors and outdoors, including pace, distance, cadence, ground time, vertical oscillation and leg spring stiffness, translating that data into one single metric known as power.
While the data is being recorded down below, you can view Stryd's data in real-time from your wrist with one of the many compatible sports watches and smartwatches.
However, these watches are also beginning to deliver their own native solutions.
Apple recently introduced running power through watchOS 9, while Garmin now offers the metric from the wrist through its more premium models, such as the Forerunner 955, Fenix 7 and Epix 2, as well as its Running Dynamics Pod.
Polar and Coros both also have dedicated pods and wrist-based estimations that have been released over the last few years, so the area is certainly growing.
One note to be aware of here, though, is that there's no standardization of running power, and this means that different companies all interpret the metric a little differently.
Real-world test: Running with power
So, we've broken down what power means in terms of running, the supposed benefits of running with power and the kit you need to make it happen.
The real question, however, is whether running with power actually works. Here's our take on running with power, both from a newbie (that's me) and a true convert.
The running power newbie, Mike Sawh
"I started learning about the idea of running power meters about a year ago when I discovered the first-generation Stryd. I'm certainly no elite athlete, but I'm definitely open to any new tech that can promise to help me run better race times.
"When I got hold of that first-gen Stryd, Jim Vance's Run With Power book arrived alongside it. I've attempted to finish the book twice and failed both times. The concept of running with power is no doubt fascinating and I'm definitely intrigued, but that book was a tall order to digest.
"Then I got my hands on the second-generation Stryd and decided to give it another try. Based on the book, I've spent the first few weeks simply running and not bothering about the numbers displayed on my Forerunner. But telling me not to look at the data has had the reverse effect. I always want to look at the numbers.
"What I see from those numbers feels very similar to the concept of heart rate training, focusing on one metric to make the most of your running sessions. The difference here is that there's far more being analyzed from a footpod than a heart rate chest strap - at least from a runner's perspective. While I've not seen any initial benefits in terms of running form - aside from focusing a little more on getting my cadence where it needs to be - being mindful of that watt data on my watch has had some impact on keeping my pace more focused.
"I'm willing to give power meters more time to win me over, but I can't help feeling like I'd need more assistance from someone that knows about running power to get the most out of it."
The running power convert, Stephen Honight, co-founder of newrunninggear.com
"I use power as a pacing metric to train and race because it gives me a better read on my effort levels. A power meter for running is measuring your movement in three planes, vertical, horizontal and lateral. Using 3D micro accelerometers, some very fast computer processing and some complex maths to compute Newtonian physics, which is Power = Force (Mass x Acceleration) x Velocity.
"Training to power has allowed me to accurately compare kilometer (or mile) splits on my run and between runs when running on varied terrain where your pace should be adjusted to maintain a consistent effort throughout. That means my power number can be the same for a km uphill and a km downhill when I'm putting in a consistent effort making it much easier to compare and be motivated by my performance on both splits. Heart rate – the only other alternative metric that can be effective at measuring effort – can change depending on my stress levels, eating habits and other external factors, whereas power is more consistent.
"For me, power has helped make a couple of big changes to my training and racing. Firstly, I now run uphill slower and downhill faster – it is hard to do in races when everyone else is running to pace. Secondly, it's helped improve my self-confidence and motivation in training when I'm running up low gradients thinking my pace is off and I'm not fit and helps me maintain a more consistent mindset while running, just like the metric being measured."
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