Smart insoles count steps of older adults

A smart shoe insole with remote monitoring provides a viable method of measuring indoor and outdoor walking in frail older adults, according to a recent study.

“To date, there is limited data in this population set. This thin instrumentation, including a flexible battery, was a technical challenge and seems to provide an acceptable solution over time that is valued by participants,” the researchers said. “However, users still raised certain acceptability issues. Given the growing interest in wearable healthcare devices, these results will be useful for future developments.”

The novel shoe insole device was tested in a multiphase study, including a single-day living lab experiment (n=9 older adults), home evaluations for a month (n=3), and a 3-month prospective randomized trial (n=35). Qualitative semi-structured interviews were used to collect data. Primary outcomes were acceptability and average time of daily wear; secondary outcome was change in physical frailty.

Acceptability was mixed during the living lab phase, with low scores for reliability but high scores for usability. Participants proposed modifications for the device, including changes to the insole’s design, the feedback app, and the synchronization protocol. The 1-month home evaluation raised no concerns. Improvements were made prior to the trial phase. [JMIR Mhealth Uhealth 2021;9:e15641]

Out of the 35 participants randomized, 25 received the insole intervention and 10 were allocated to the control group. Nine dropped out in the intervention group. Of the 16 participants remaining, 10 were very satisfied and three were quite satisfied with the device’s comfort at follow-up. The discontinuations were due mostly to technical difficulties with the device.

Participant acceptability at 1 month was 63 percent, which dropped to 50 percent at 2 months and rebounded to 75 percent at 3 months.

Six participants were unable to wear the insoles for more than a week due to technical problems. All the remaining participants reported that they wore the device every day at the 1-month follow-up. Daily use was 83 percent at 2 months and 94 percent at 3 months. Corresponding durations of device use per day were 5.8±2.9, 6.3±6.4 and 5.1±3.7 hours.

The overall average number of days the insole was worn was 29.2±28.7 days, which rose to 40.4±28.8 days when excluding the six participants with less than a week of use. Insoles were worn for a mean of 5.6±3.7 hours per day overall.

“Wearable connected sensors are promising for real-life monitoring and appear to be a solution in improving physical activity promotion in frail older adults. However, optimal deployment of wearable health devices will require further research conducted in real-life conditions to test acceptability, effectiveness, and costs,” the researchers said.

“This study reports real-life acceptability data on an instrumented insole in frail older participants over a 12-week period. These results are informative in terms of technical choices for those who wish to instrument a shoe insole,” they added.