Katrien Fischer – “The effect of an intervention with virtual coaches on the physical activity of adults aging 55 years or older”


StudentKatrien Fischer
StudyFree University of Amsterdam, Faculty of Behavioural and Movement Sciences
Host OrganisationRoessingh Research and Development
Finalized DateJune 2020


With an increasing life expectancy of the older adult population, being physically active is very important. Maintaining a healthy lifestyle can be supported by virtual coaches. It can change the motivation of a user, their behavior, beliefs or attitudes. The Council of Coaches’ functional demonstrator, a web-based eHealth application, will be evaluated within this study, with a focus on the virtual physical activity coach, Olivia Simons. The aim of this assignment is to assess the effect of a virtual physical activity coach on physical activity levels by implementing the functional demonstrator in a real-life setting among older adults aging 55 years or older.

Results & Outcomes

This assignment was part of the final evaluation of the functional demonstrator, and focuses on Fitbit step data of the baseline week (1 week) and implementation phase (4 weeks) of the first round, and on Olivia (the physical activity coach). The study population consisted of 25 Dutch older adults, with a mean age of 66.5 years old (SD=7.5). With the collected Fitbit data, the average number of steps per day in all five weeks was calculated, see Boxplot below. The median steps per day in each week fluctuated around 9000 steps. With the Friedman test, no significant result was found between the different weeks.

One participant did not interact with Olivia during the implementation phase. During the first week of the implementation phase, most participants interacted with Olivia, and the mean duration of the interaction was highest, namely 14.7 minutes (SD=18.1). The mean duration of the interaction with Olivia was lowest during the third week of the implementation phase: 4.7 minutes (SD=4.6).

The following factors for interacting with Olivia were mentioned:

  • Health pressure (N=14): wanted to receive advices, ideas on how to stay physically active.
  • Enjoyment (N=9): interested in what Olivia had to offer them.
  • Positive health (N=4): wanted to be conscious of how to get a healthy body.

In conclusion, this study did not show that physical activity of adults aging 55 years or older was stimulated by an intervention with virtual coaches. The number of steps did not significantly increase and older adults will use a virtual physical activity coach mainly for health pressure. The virtual coach makes users more aware of daily movement and confronts and stimulates them. However, future studies are needed, in which it is important to make sure that the participants cannot receive notifications or feedback on the Fitbit. Also, a follow-up study must take participants’ fitness into account and find out the findings for the long-term of using an e-health application.