JMIR Publications

ABSTRACT

Background:

Adopting an active lifestyle plays a key role in the prevention and management of chronic diseases such as type 2 diabetes (T2D) and cardiovascular disease. Web-based interventions are able to alter health behaviors and show stronger effects when they are informed by a behavior change theory. ‘MyPlan 2.0’ is a fully-automated e- and mHealth intervention targeting physical activity (PA) and sedentary behavior (SB), based upon the Health Action Process Approach (HAPA). The programme aims to alter behavior by targeting HAPA-based personal determinants for change.

Objective:

Our objective was to test the short-term effect of ‘MyPlan 2.0’ in altering levels of PA and SB and in changing personal determinants of behavior in adults with T2D (RCT 1) and in adults aged ≥50 (RCT 2).

Methods:

The study consisted of two randomized controlled trials with an identical design. RCT 1 was conducted with adults with T2D. RCT 2 was performed in adults aged ≥50. Data were collected via face-to-face assessments. Participants decided either to increase their level of PA, or to decrease their level of SB. Participants were randomly allocated with a 2:1 ratio to the intervention group or the waiting-list control group. They were not blinded for their group allocation. Participants in the intervention group were instructed to go through ‘MyPlan 2.0’ consisting of five sessions with an interval of one week between each session. The primary outcomes were objectively-measured and self-reported PA (i.e. light PA, moderate-to-vigorous PA, total PA, number of steps and domain-specific (e.g. transport-related) PA) and SB (i.e. sitting time, number of breaks from sitting time and length of sitting bouts). Secondary outcomes were self-reported behavioral determinants for PA and SB (e.g. self-efficacy). Separate linear mixed models were performed to analyse the effects of ‘MyPlan 2.0’ in the two samples.

Results:

In RCT 1 (n=54), the PA intervention group showed, in contrast to the control group, a decrease in self-reported time spent sitting (P=.09) and an increase in accelerometer-measured moderate (P=.05) and moderate-to-vigorous PA (P=.049). The SB intervention group displayed an increase in accelerometer-assessed breaks from sedentary time in comparison with the control group (P=.005). Fourteen participants of RCT 1 dropped-out. In RCT 2 (n=63) the PA intervention group showed an increase for self-reported total PA in comparison with the control group (P=.003). Furthermore, in contrast to the control group, the SB intervention group decreased their self-reported time spent sitting (P=.08) and increased their accelerometer-assessed moderate (P=.06) and moderate-to-vigorous PA (P=.07). Eight participants of RCT 2 dropped-out.

Conclusions:

For both samples, the HAPA-based e- and mHealth intervention ‘MyPlan 2.0’ was able to improve only some of the primary outcomes. The discussion provides several points for further improvement. Clinical Trial: The protocols for the randomized controlled trials were registered as clinical trials on https://register.clinicaltrials.gov (NCT03291171 (RCT 1); NCT03799146 (RCT 2)).