Darcy Ummels

96 | Chapter 5 Participants Twenty older adults were recruited from several local associations for older adults (e.g., bridge club or church association) in the South of the Netherlands. Participants were included if they were older than 65 years and didn’t meet the Dutch physical activity guidelines (a minimum of 150 min of moderate ‐ intensity per week). 23 Exclusion criteria were insufficient understanding of the Dutch language, use of a walking aid, and a pathological gait during the 10 ‐ metre walk test (10MWT) observed by a physiotherapist. 24 All participants provided written informed consent prior to inclusion. Activity protocol A participant ‐ determined sequence activity protocol was developed based on ADL. To simulate free ‐ living, participants were free to choose the order and duration of a series of daily activities. The activity protocol, shown in Table 5.1, was based on earlier activity protocols with ADL in people with chronic diseases and older adults. 20,25 ‐ 28 Table 5.1 The Participant ‐ Determined Sequence Activity Protocol with Activities of Daily Living for Older adults. Activity type Defined for the gold standard as Squat a Marks start of the protocol Organising a cabinet with cutlery, plates, and cups Standing Reading the newspaper while seated at a table Stedentary Ironing and folding laundry Standing Sitting and talking Sedentary Washing the dishes Standing Sweeping the floor Dynamic Changing linens on a bed Dynamic Setting the table with cutlery, plates, and cups Dynamic Squat a Marks end of the protocol a Squat was mandatory at the beginning and at the end of the activity protocol and was not used for analysis. Activity trackers The MOX Activity Logger 29 contains a tri ‐ axial accelerometer (ADXL362, Analog Devices, Norwood, MA, US). This small, lightweight, waterproof device (35 mm x 35 mm x 10 mm, 11 g) measures raw acceleration data (±8 g) in three orthogonal sensor axes (X, Y, and Z) at a 25 Hz sampling rate. The raw data is stored directly on the internal memory. The MOX has storage capacity and battery life for continuous measurements up to 7 days. Device configuration, data transfer and charging of the device are possible via an USB connection. Data analysis is performed offline. The MOX was worn in the front trouser