A workout shirt that measures electrical activity in muscles has been developed by engineering students who hope that the technology can guide not only those who train in gyms but also those undergoing physical rehab programs.
Wearable fitness trackers such as the Nike+ FuelBand and Fitbit rely on accelerometers to count the number of steps walked and other personal metrics. While generally reliable, the measurements recorded using this technology is not always accurate, and may fool users into thinking they are expending less energy during a workout than they actually have.
Most devices in the market today use accelerometers to detect body movement but a better measure of biomechanics can be provided by electromyography (EMG). Used in the clinical setting to study kinesiology and neuromuscular conditions, EMG measures the electrical activity produced by skeletal muscles as they relax and contract.
Research students at the University of Waterloo used EMG for an award-winning project called WearAbility that involved creating a shirt that measures electrical activity as the wearer performs a workout routine. Data is then sent wirelessly to a smartphone where the user can see exercise metrics such as number of reps or sets, cadence, peak effort and mean effort.
Electrodes placed on the skin are connected to a printed circuit board which sits inside an enclosure designed using SolidWorks software. The enclosure was created using a 3D printer and the whole prototype is a box small enough to carry inside a backpack.
They then developed software that could process four channels of EMG data using customized algorithms. The data is then transmitted to a smartphone via Bluetooth, and the user can see metrics represented by numbers, circles and graphs in an intuitive user interface, instead of the more technical-looking waves in a traditional electromyogram record used in clinics and hospitals.
“We spent most of our time developing the workout application, creating the activation profile, measuring mean activation peaks, figuring out how to bring data to the workout. Now we are interested in commercial applications, including exercise at home programs,” said Marc-André Simard, one of the team members involved in the project which won $13,000 in the Norman Esch Entrepreneurship Awards for Capstone Design at the University of Waterloo.
The team is looking to spend the fresh funding to improve their prototype shirt by finding ways to integrate dry electrodes and thinner wires into the shirt, fine-tune exercise algorithms and add the ability for data sharing among friends using the app. The EMG WearAbility shirt has the opportunity to stand among established brands in the increasingly crowded wearables market by offering the workout shirt itself as the tracker instead of forcing the user to wear an accessory device on the wrist, arm or waist.
The market for wearable fitness sensor devices is expected to hit 56.2 million global shipments by 2017 according to a report by IMS Research. Booming demand for wearables is fueled by the current fitness craze and the quantified self movement. Researchers like the ones who created the EMG workout shirt may eventually find commercial success with the rising demand for fitness trackers.
The WearAbility team wants their product to be used eventually not just by gym rats, fitness freaks and athletes but also by others taking part in a physical therapy regimen for a disability or neuromuscular condition. It could also be a low-cost device for home exercises or used by employees in a workplace injury prevention and wellness program that could lower the incidence of low back pain, neck strain and work-related injuries.