How fast a person walks can help predict health issues such as cognitive decline as well as cardiac and pulmonary diseases. Slow walking speed may also be attributed to heart, lung, and nervous system problems and joint pain.
Research has shown that people whose walking speed is slower than 0.6 meters per second (2 feet per second) may have increased odds for poor health and function.
Accurately monitoring a person's walking speed though poses challenges in that it has to be continuous and unobtrusive at the same time.
Monitoring A Person's Walking Speed
Clinicians and physical therapists currently use a stopwatch to measure walking speed. Wearable devices such as Fitbit activity trackers only provide a rough estimate of speed based on step count. Wearables may also cause an unwanted reaction.
In 2014, Fitbit faced a class-action lawsuit stemming from a series of reports of users experiencing skin irritation as a result of using the company's fitness tracker. Users of the Fitbit Force fitness tracker reported rashes, peeling skin, and blisters.
GPS-enabled smartphones also tend to give inaccurate measurements and may not even work indoors. Cameras may be used but they can be intrusive and one camera is needed for each room.
Measuring Walking Speed Using Wireless Signals
A group of researchers from MIT's Computer Science and Artificial Intelligence Laboratory has thought of a solution and developed a device capable of measuring the walking speed of several individuals using wireless signals.
The device, known as WiGait, is 95-99 percent accurate and emits a signal equivalent to about a hundredth of the amount of radiation emitted by cellphones. Being the size of a small painting, it can be mounted on the walls of a house.
The device also has an accuracy rate of 85-99 percent accurate when it comes to measuring an individual's stride, which may provide information on conditions that are marked by reduced step size, such as Parkinson's disease.
What makes WiGait better than currently used methods and devices is that is can measure a person's walking speed at a greater level of detail sans the need to carry or wear a sensor.
How WiGait Works
It works by analyzing the wireless signals and how these are reflected off a person's body. It also uses an algorithm that can differentiate walking from other movements such as those involved when a person brushes teeth or cleans the kitchen.
Wirelessly Monitoring Walking Speed May Provide Important Health Information
WiGait's developers said that the device may offer crucial health information especially for the elderly. Changes in walking speed, for instance, could mean that a person is injured or is at an increased risk of falling. The feedback system may even help determine if there is a need for a person to transfer to a different environment where he or she can be better assisted.
"Many avoidable hospitalizations are related to issues like falls, congestive heart disease, or chronic obstructive pulmonary disease, which have all been shown to be correlated to gait speed," said Dina Katabi, who is part of the MIT team that developed the device.