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Demystifying running metrics to turn you from a data skeptic into a a data addict

Which category of data-driven runner do you fall into?

1. The Data Addicted Runner

The data addicted runner is strapping every gadget on their body as possible and enabling as many features as those gadgets allow. They are pooling all their data into their training platform and, with a few taps on the keyboard, conjure up some unique insight that uncovers something they did not previously know about.

This group is relatively small and their mystical data sifting ways are not entirely understood by a large majority of runners, but their process seems to work for them.

Unless you are fully bought into this first group and their ways, you probably are not a data addict. Rather, you are at least partially "data fearful."

2. The Data Fearful Runner

Far more commonly, I meet the data fearful runner.

This group actually likes data and does not want to avoid data. They know data can be helpful and empowering in achieving their goals.

But, they are cautious to spend too much on gadgets to collect the data and they are especially afraid to spend too much time analyzing that data to get nothing out of the experience besides the frustration in making heads or tails out of what they are analyzing.

The Data Fearful runner often asks me, "Do I really need more data?"

And, it is a good question to ask if you take a look at the list of metrics that Stryd reports:

Power Metrics: Power, Form Power, Air Power

Form Metrics: Cadence, Ground Time, Vertical Oscillation, Leg Spring Stiffness

Tracking Metrics: Pace, Distance

Well, if you look at the purpose of each metric, it makes a lot of sense to see why this data is necessary and how each piece accomplishes a unique goal that cannot be accomplished using traditional metrics provided by a GPS watch such as heart rate or pace.

Let's take a look the purpose of each of these metrics.


Power Metrics

- Power

Power comprehensively considers the conditions you are running in, such as wind and hills, to guide you to run at the correct intensity.

Running at the correct intensity is important because that means you can best achieve the goal of whatever workout you are trying to complete that day as part of your structured training plan. Or, it means that you can run to your limit on race day, regardless of the course or weather conditions.

- Form Power

Form Power is the power not being used to move you forward. Essentially, it is the power required to maintain your running form.

If you can minimize your Form Power, you can use more of your power for forward movement.

- Air Power

Air Power is the power required to overcome air resistance.

If you can minimize your Air Power by drafting, you can save more power that can be used for forward movement.

Alternatively, if you properly consider the power required to overcome gusting winds, you can wisely slow down to not burn yourself out in windy conditions.

Form Metrics

I am going to skip Cadence, Vertical Oscillation, and Ground Time since these are fairly well known metrics and there is not necessarily an ideal value you need to target for any of these metrics. i.e. a higher cadence is not always better and a lower cadence is not always worse. One of the major reasons that Stryd features these metrics so you have a quantifiable and repeatable way to see if your form is changing as a result of doing supplemental drills such as plyometrics or hill sprints. If you do want a deeper explanation Ground Time and Vertical Oscillation, you can find that on Page 15 here: https://www.stryd.com/guide

- Leg Spring Stiffness

Leg Spring Stiffness is a measure of how well a runner recycles the energy applied to the ground.

Think of your leg as a spring upon which your body “bounces.” The stiffer the spring, the less energy you must produce to propel yourself forward with each step.

If you can improve your Leg Spring Stiffness, you will be getting more "free" energy from every stride you take.

Tracking Metrics:

- Pace

Why do you need pace from Stryd if you already have pace from GPS?

Stryd's pace metric is more responsive and less random than GPS. This means it is easier and quicker to quickly dial into your desired running speed by looking at Stryd's pace metric on your watch instead of waiting for GPS's pace to settle in to the correct value.

Responsive pace is especially important when you first receive Stryd because you will be using this metric during your first few weeks of running with Stryd as your shift over to running based on power.

Additionally, Stryd's pace value gives you a single pacing experience for your year round training. You won't need to switch from GPS when running outdoors to another pace source when you are forced indoors to your treadmill. Stryd's pace value is reliable and consistent for every run.

- Distance

Stryd's distance is consistent and accurate like Stryd's pace value, so it is useful in the same ways.

Stryd's distance value is particularly useful used when running indoors on a track or a treadmill, where GPS does not work, or when running on an outdoor track, where GPS will shortchange your distance.


There is no "fluff" to be found in Stryd that would complicate your data analysis process. In fact, the addition of this new data from Stryd will likely simplify your data analysis process as you can quickly discover exactly what you want to be looking at without needing to be limited to incomplete views of your run using less granular metrics such as GPS pace or heart rate.

With the help of Stryd, you may turn from a data skeptic into a data addict once you discover how much more you can learn from each of your runs.

If you want to order Stryd and begin running with power, you can do that here:


Angus Nelson

Angus Nelson

Angus is a cofounder of Stryd. He has trained for and raced every distance from 50 meters to Half Ironman & is pushing the run power revolution forward!

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