A Beginner’s Guide To Running Metrics

I am a beginner runner who has only been running for a few months. Currently, I am preparing for a half marathon in Toronto and looking to complete my first ever race under 2 hours.

Over the course of the last few months, I have not only improved my running but also gathered a great deal of knowledge about various aspects of running. By virtue of my professional career where I deal with a lot of data, I have always been keen to measure every aspect of my running so that I can analyze them in order to be a better runner.

In this article, I describe various metrics that I measure for my runs and use frequently to improve my running.

Category 1: Running Mechanics

Cadence: Cadence or stride frequency is measured by how many steps a runner takes per minute. Some applications also measure cadence as revolutions per minute which is steps per minute divided by 2. Maintaining a cadence of close to 180 steps per minute (SPM) is often advised by many experts. A better cadence improves running efficiency and prevents injuries.

Stride Length: Stride length is a very self-explanatory metric as it measures the average length of the stride of a runner. Stride length can vary vastly depending on the strength and mobility of a runner. The important thing is to maintain an optimum stride length without overstriding.

It is important to note that:

Distance covered in a minute = Cadence (SPM) * Average stride length

So, in order to cover more distance and become faster, we need to improve these metrics and create a balance between the two. Below you can see my cadence and stride length details from one of my recent runs.

Cadence and Stride Length data from Stryd Powercenter and Strava Elevate

There are 3 other metrics that are somehow related to cadence. A better cadence usually helps improve all 3 of them.

Ground Contact Time: The average amount of time a runner is in contact with the ground in each step. This is usually measured in milliseconds (ms). It is often mentioned that elite runners have less than 200 ms of average ground contact time. A lower ground contact time similar to cadence improves running efficiency and prevents injuries.

Vertical Oscillation: Vertical oscillation is the measure of the vertical displacement of a runner’s torso to understand the extent of bounce while running. It is usually measured in centimeters (cm). In running, our goal is to move in the horizontal direction. So, reducing the vertical oscillation will help improve running economy and waste less energy for vertical motion.

Vertical Ratio: Vertical ratio is the ratio of vertical oscillation and stride length. The lower the vertical ratio, the better the running efficiency.

Here is an example of “Ground Contact Time” and “Vertical Oscillation” from one of my recent runs:

Vertical Oscillation and Ground Contact Time data from Stryd Powercenter

Category 2: Power, Heart Rate & Related Metrics

Heart Rate: Heart rate has been considered one of the important metrics not only for running but for any activity. Many runners want to maintain certain heart rate zones while they train. Heart rate is measured as beats per minute (BPM). Heart rate can vary depending on multiple factors such as age, physical condition, weather, etc. The most popular way to measure the maximum heart rate of a person is by subtracting age from 220

Here is an example of heart rate and heart rate zones:

Heart Rate data from Stryd Powercenter and Strava Elevate

Power: Running power is a relatively new metric that is very popular in the cycling world. But in recent years because of the advancement of technology, running power has become more and more commonplace among runners. Power is a measure of output a runner is producing while running. The unit used to express power is Watt (W). One of the biggest advantages of using power over heart rate is power is an instantaneous indicator. Any change is running effort will display an immediate change in power. While heart rate is a lagging indicator which means when a runner is putting more or less effort it takes some time to see the change in the heart rate. Also, power doesn’t depend on any external factors as heart rate does.

Here is an example of my running power:

Power data from Stryd Powercenter and Strava Elevate

Intensity Factor: Intensity factor is a ratio of normalized or average power for a run divided by critical or functional threshold power (FTP) of a runner. There are multiple methods of measuring FTP which signifies the power a runner can hold for a significant amount of time. FTP will change over the course of time as a runner gains more experience of holding a higher power.

The following IF is measured based on an FTP of 180 W

Intensity Factor data from TrainingPeaks

Intensity Factor (IF) is calculated as 190 / 180 which is 1.05

Efficiency Factor: Efficiency factor (EF) is a ratio of normalized or average power and heart rate when both power and heart rate have been tracked. Increase in efficiency factor indicates an improvement in aerobic fitness

Aerobic Decoupling: Aerobic Decoupling (Pw:Hr) is the comparison of the efficiency factor between the first half of the activity and the second half of the activity. A smaller value of aerobic decoupling signifies better aerobic fitness.

Here is an example of these two metrics:

Aerobic Decoupling data from TrainingPeaks

Efficiency factor (EF) is determined by dividing normalized power (NP) with Avg heart rate

207 (W) / 166 (BPM) = 1.25

Aerobic decoupling (Pw:Hr) for this run was 6.89%

Category 3: Pace, Grade Adjusted Pace, Elevation

Pace & Grade Adjusted Pace (GAP): Pace is one metric that I consider a reflection of a runner’s current ability based on the input provided during the activity. Most of the training methods are comprised of sessions where a different pacing zone needs to be maintained. The pacing zone should also be created based on a runner’s ability. So, an 8 min/mile (5 min/km) pace can be a tempo pace for a beginner runner but for an experienced runner that could be an easy or recovery pace.

Grade adjusted pace (GAP) is adjusted pace when elevation is taken into account.

Here are some examples of pace and GAP:

Pace and GAP data from Strava

Elevation: Hill training is a staple of every runner’s training schedule. So, it would be interesting to see the elevation gain and loss during a running activity.

Here is an example of the elevation gained and lost for my run:

Elevation data from TrainingPeaks

This will bring an end to this post. Feel free to comment if you have any questions regarding the metrics as it will help all of us to be a better data-driven runner. Happy running!