With the warmer weather upon us, many will be lacing up their sneakers to step out for a run. As we consider our running pace, we might assume that as we log further distances, we will naturally start to slow our pace to conserve energy. A new study led by Queen’s researcher Jessica Selinger (School of Kinesiology and Health Studies) challenges that view.  

“We often run at the same speed, regardless of distance, because that particular speed is the most energetically efficient,” Dr. Selinger says.

The research study, published in Current Biology, analyzed data from more than 4,600 runners totaling more than 28,000 hours of running. Researchers compared energy-saving running speeds measured in a lab setting to the preferred, real-world speeds measured by wearable trackers and found the two to be indistinguishable.

The researchers gathered data from 26 runners on treadmills and identified the energetically optimal speeds based on their oxygen consumption. They compared this to data collected from thousands of recreational runners outfitted with a waistband tracker from Lumo Run.

The findings show that the preference for energy efficient movement is strong. Even when we go for a jog, with the goal of burning calories, we move at a speed to minimize them.

“This means that if we want to run at a faster pace, we may need to consciously focus on doing so. Or, use other tricks like running with a faster partner or listening to fast paced music,” says Dr. Selinger. “It is important to understand what objectives shape our locomotion, and what influences how we move if we are looking to train athletes, develop assistive devices, or even understand our evolutionary history.”

There are evolutionary advances to moving in an energy optimal way — we can travel further on few calories.

“We share this trait with other animals, be it flying birds, swimming fish, or galloping horses – there's evidence that we all move in calorie conserving ways out in the wild,” Dr. Selinger explains.

The runners that Dr. Selinger and her team analyzed in the lab were limited to younger, fit individuals.

“In the future, it would be really nice to have the lab-based energetic measures for a broader swathe of the population,” she says.

Although the data from lab studies may be more consistent and manageable, Dr. Selinger, the study's lead author who started the research as a postdoctoral scholar at Stanford University, said that the sheer volume of information made available through wearables is unobtainable in the lab.

“Wearables can also reveal the choices we make in the real-world without the oversight of a researcher or constraints of the lab environment. By fusing the two, a new window has opened up into runners' behaviour,” Dr. Selinger says.

By applying useable data from wearables, and perhaps improving wearables by adjusting algorithms according to research results, the researchers envision expansive ways to enable fitness based on natural, “free-living” human behaviour.

The study is now available in Current Biology.