Movement Maps

by | Nov 12, 2019

A new way to visualize the way you move.

We’re excited to announce the release of Movement Maps — a tool to look at walking and running in great visual detail.

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Movement maps show the movement of both feet along each of the six axes measured by our sensors, over the course of a step. They are unique to each person and represent a qualitative measure of movement dynamics.

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All six axes captured by our sensor.

A step is shown as one circuit through the movement map phase space diagram, and each additional step is plotted on top of the previous step. You can see how the movement map is created by the movement of both the left and right feet in the video below.

For each activity, there are a set of six maps, each of which represents one direction of acceleration or rotation. Each map shows the left limb movement on the left side and the right limb movement on the right side.

With these maps, you can see both the left-to-right limb asymmetry and the the step-to-step variability of each limb. Symmetrical movements will look like a mirror image on both sides of the centre line, while for asymmetrical movements, one side of the plot will be smaller and one side will be larger. In movements with low variability, the plot will appear as a solid line as the same step circuit is repeated multiple times. In movements with high variability, the plot will appear fuzzy, as the circuit changes with each step.

How to use movement maps

By looking at all six maps for one activity, you can see which type of acceleration or rotation contributes most to overall left-to-right asymmetry.

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Movement maps for a short walk, where all movements except coronal rotation are fairly symmetrical for the left and right limbs.

By comparing the maps of the same movement between two different activities, you can see which activity had higher asymmetry or higher variability.

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Coronal rotation for two different activities. Activity 1 is fairly symmetrical; activity 2 is asymmetrical.
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Lateral accelerations for two different activities. Activity 1 has high variability and activity 2 has low variability.

The image below shows six movement maps generated over ten weeks for a patient recovering from ACL reconstruction surgery. The first map shows high asymmetry between the left and right limbs. At ten weeks, normal symmetry has returned. By monitoring movement maps for the same person over time, you can see trends in their movement signature.

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How to see movement maps

Movement maps are most valuable for walks and runs of between 1 and 2 minutes. To compare maps between different activities, consistency is important: the walk or run should be performed at the same speed, for the same amount of time, and on the same surface.

In the Info data view for a walk or run activity under Extra Files, click on “Generate Movement Map.”

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Once the map has been generated, click the link to download.

Read more about movement maps here.

Kay Penney
Kay Penney

Product & Ops at Plantiga

give us those e-digits.
you won't regret it.

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