such as cadence or step rate, as well as muscle strength and flexibility, explains?

From cadence to stride length and heart rate to calories burned, there’s an abundance of measurements and markers most smart watches can track these days. One metric you may have noticed even if you haven’t zeroed in on it is vertical oscillation, which can have an effect on your efficiency What determines vertical oscillation.

Here’s what to know about this often-overlooked running metric and how it can affect performance.

Vertical oscillation, also often referred to as vertical displacement, refers to how your entire body moves up and down while running, according to Bryan Heiderscheit, P.T., Ph.D., a professor in orthopedics and vice-chair for research for the department of orthopedics and rehabilitation at the University of Wisconsin Madison. In other words, that’s where the “spring in your step” comes into play when you’re running.

While some degree of vertical movement when you run is obviously natural, too much or too little of it can lead to inefficiencies, such as shuffling your feet if too low, and an over-expenditure in energy if too high.

In other words, you bounce when you run, and the amount that you bounce is important because it affects your running efficiency, specifically the mechanical work your muscles do when you run. It also influences your metabolic efficiency (i.e. how much oxygen you need while running), Heiderscheit says.

“If you have a very low vertical oscillation, or bounce, below 5 centimeters, that can be very inefficient, and if you run with a lot of vertical oscillation, above 10 to 12 centimeters, that can also be very inefficient,” Heiderscheit tells Runner’s World.

How to Treat Tight Calves running form, How to Adjust Your Run Schedule After a Big Race Colleen Brough, P.T., D.P.T., an assistant professor of rehabilitation and regenerative medicine at Columbia University Irving Medical Center and director of Columbia RunLab

“Factors contributing to excessive vertical oscillation include decreased gastrocnemius and soleus flexibility (or tight calf muscles), and How to Treat Tight Calves,” she says. “Tight calves will cause more vertical oscillation [due to] early heel rise and prevent the leg from moving into full hip extension, [making you go up] instead of forward.”

Cadence affects vertical oscillation because you’re making an effort to have faster turnover, which makes you tend to draw the foot closer under your center, thus minimizing up and down movement, Brough says.

According to Brough and Heiderscheit, an optimal measurement of vertical oscillation is anywhere between 5 and 10 centimeters. While it’s possible for runners to experience either too much or too little vertical oscillation while running, “over-bouncing,” or too high vertical oscillation, is more prevalent, and there are ways you can change your running style with the guidance of an expert such as a physical therapist, Heiderscheit says.

“When you think about vertical oscillation, there are two elements to it: the high point, called the flight phase, where both feet are off the ground and your whole body is up in the air at the highest point, and then there’s the low point of vertical oscillation, which is the mid-stance phase, when your one leg is on the ground and your knee is bent and you’re sinking low,” Heiderscheit expalins. “Runners can either be too high or too low [at those points].”

According to Heiderscheit, runners should aim to minimize time on the ground by manipulating their step rate or foot ground contact time. This helps to increase their cadence, What determines vertical oscillation.

Many GPS watches, including those by Garmin, COROS, and Apple Watch, include vertical oscillation, sometimes also referred to as stride height, as one of the measurements you can track in your data, which Brough and Heiderscheit believe to be fairly accurate (though there’s no research to confirm just how accurate).

You can also try to manually capture a measurement by setting up your smartphone to film a 10-second video while you’re running on a treadmill or as you run past the camera on flat terrain outside. After recording, measure the distance in up-and-down movement from a certain marker, such as your nose or shoulder, Brough says. (You’ll have to watch in slow-mo to capture that distance.)

According to Brough, vertical oscillation is an important running metric to be mindful of because it can be indicative of injuries. According to a small study Achilles tendinitis, or bone stress reactions or Other Hearst Subscriptions in 2018, those with a vertical oscillation that is too high experience an increase in impact force when their feet hit the ground, which in turn increases their risk of injuries, especially bone and joint stress injuries.

The study found that reducing runners’ vertical oscillation, and increasing cadence, resulted in less ground reaction forces, which is key for preventing injury.

“Vertical oscillation is often a yellow flag that a runner may have some path of mechanics going on with their form that is consistent with a lower extremity injury,” Brough tells Runner’s World. “Runners with How to Increase Running Cadence and tight calves have a limited ability for their foot to remain on the ground and move back behind them, to really get a healthy, strong push-off. So when [the leg doesn’t move back], you see increased vertical excursion, where instead of having that foot stay on the ground and the leg move back behind them, it comes off of the ground. This results in overstriding, which is consistent with lower extremity injury, both soft tissue injury as well as bone and stress injuries, such as plantar fasciitis, Advertisement - Continue Reading Below fractures.”

According to Brough and Heiderscheit, there hasn’t been research to show that suboptimal vertical oscillation can negatively affect running performance in terms of preventing runners from achieving goal times. However, because it has been associated with stress injuries, it can be worthwhile to determine your vertical oscillation to see if any adjustments can be made.

As for how to change your vertical oscillation to reach that optimal level of 5 to 10 centimeters, Brough recommends increasing your step rate or cadence. While you can also turn to your smartwatch data to view cadence, you can also determine your cadence by counting the number of steps you’ve taken in 30 seconds, Brough says.

Then, work to increase your step rate by either using a metronome app, such as Metronome Beats, or finding playlists on Spotify that feature songs with a tempo of 155 beats per minute, for example, which is a tangible place to start on your own if your current cadence is around 140 to 150 steps per minute, as this would increase it by 5 to 10 percent. (If you’re working toward a faster cadence, up those beats per minute for your playlist!)

“This is a more fun and exciting way to be able to do this on your own and one that doesn’t require spending money to see a physical therapist or a doctor,” Brough says.

Emilia Benton

Contributing Writer

Emilia Benton is a Houston-based freelance writer and editor. In addition to Runner's World, she has contributed health, fitness and wellness content to Women's Health, SELF, Prevention, Healthline, and the Houston Chronicle, among other publications. She is also an 11-time marathoner, a USATF Level 1-certified running coach, and an avid traveler.