Establishing Walking-related Digital Biomarkers in Rare Childhood Onset Progressive Neuromuscular Disorders

Six Minute Walk Test

Participants will complete the six minute walk test in a corridor which includes the instrumented walkway, while wearing the insoles. This is to measure spatial parameters, kinetic parameters, temporal parameters, and metrics of cumulative activity in order to compare against the gold standard instrumented walkway. The six minute walk test is an objective evaluation of functional exercise capacity, and measures the maximum distance a person can walk in six minutes over a 25 meter course.

10 Meter Walk/Run

Participants will walk, or run if able to, for 10 meters on the instrumented walkway while also wearing the insoles. This will be done to measure spatial parameters, kinetic parameters, temporal parameters, and metrics of cumulative activity in order to compare against the gold standard instrumented walkway. This outcome is reported as the time it takes for the participant to complete 10 meters as fast as possible.

Time Up and Go Test (TUG)

Participants will complete the TUG test. This is a timed test of mobility, requiring the participant to stand up from a seated position, walk 3 meters and return to sitting in the chair. The outcome reported is the time it takes for the participant to complete the sequence.

Muscle Strength Testing with Hand-held Dynamometry (HHD)

HHD is used to assess the strength of muscles and is reported as the maximum strength exerted in pounds (lbs).

Free-living Testing of Instrumented Insoles

To determine spatial parameters, kinetic parameters, temporal parameters, and metrics of cumulative activity using instrumented insoles, participants with SMA, DMD, and healthy controls will be asked to wear the insoles along with a validated activity tracker. Participants will be asked to wear the insoles during a single day visit to the lab, and then for at least 180 hours at home in a real-life environment. Participants will be asked to wear the insoles and activity tracker for at least 6 hours per day when at home. Compliance with this outcome will be measured in total hours the insoles are worn over the study period (one month).

Validation of Physical Activity using Actigraph accelerometer

An Actigraph will be provided and worn during waking hours, while the participant is also wearing the insoles. Data extracted are counts per minutes, and are measurements of movement performed in both vertical and horizontal axis. The counts will be used to quantify the time the participant is inactive, low, moderate and / or in vigorous physical active.

International Physical Activity Questionnaire-Short Form, IPAQ-SF

The IPAQ-SF is a self report questionnaire that assesses the types of intensity of physical activity and sitting time that people do as part of their daily lives. It is used estimate total physical activity in MET-min/week and time spent sitting in the 7 days prior to completing the questionnaire. It will be completed by participants aged 18 and over, at the start and at the end of the one-month insole wear time.

PROMIS Pediatric Physical Activity Questionnaire

The pediatric activity questionnaire measures a child's self-report of short bouts of moderate to vigorous physical activity. This questionnaire is designed to measure constructs best recalled by children such as physiological response, symptoms, and short bouts of higher intensity activity. The questionnaire has an 8-item bank and is intended for use with children ages 8 to 17 years or with a parent proxy version for children aged 5 to 17 years. It will be completed at the start and at the end of the one month insole wear time and scores will calculated and range from 8-40.