Physical activity (PA) is associated with benefits, such as fewer depressive symptoms and loneliness. Web- and print-based PA interventions can help older individuals accordingly.We aimed to test the following research questions: Do PA interventions delivered in a web- or print-based mode improve self-reported PA stage of change, social-cognitive determinants of PA, loneliness, and symptoms of depression? Is subjective age a mediator and stage of change a moderator of this effect?Overall, 831 adults aged ≥60 years were recruited and either allocated to a print-based or web-based intervention group or assigned to a wait-list control group (WLCG) in 2 community-based PA intervention trials over 10 weeks. Missing value imputation using an expectation-maximization algorithm was applied. Frequency analyses, multivariate analyses of variance, and moderated mediation analyses were conducted.The web-based intervention outperformed (47/59, 80% of initially inactive individuals being adopters, and 396/411, 96.4% of initially active individuals being maintainers of the recommended PA behavior) the print-based intervention (20/25, 80% of adopters, and 63/69, 91% of maintainers) and the WLCG (5/7, 71% of adopters; 141/150, 94% of maintainers). The pattern regarding adopters was statistically significant (web vs print Z=-1.94; P=.02; WLCG vs web Z=3.8367; P=.01). The pattern was replicated with stages (χ24=79.1; P<.001; contingency coefficient 0.314; P<.001); in the WLCG, 40.1% (63/157) of the study participants moved to or remained in action stage. This number was higher in the groups receiving web-based (357/470, 76%) or print-based interventions (64/94, 68.1%). A significant difference was observed favoring the 2 intervention groups over and above the WLCG (F19, 701=4.778; P<.001; η2=0.098) and a significant interaction of time and group (F19, 701=2.778; P<.001; η2=0.070) for predictors of behavior. The effects of the interventions on subjective age, loneliness, and depression revealed that both between-group effects (F3, 717=8.668; P<.001; η2=0.018) and the interaction between group and time were significant (F3, 717=6.101; P<.001; η2=0.025). In a moderated mediation model, both interventions had a significant direct effect on depression in comparison with the WLCG (web-based: c' path -0.86, 95% CI -1.58 to -0.13, SE 0.38; print-based: c' path -1.96, 95% CI -2.99 to -0.92, SE 0.53). Furthermore, subjective age was positively related to depression (b path 0.14, 95% CI 0.05-0.23; SE 0.05). An indirect effect of the intervention on depression via subjective age was only present for participants who were in actor stage and received the web-based intervention (ab path -0.14, 95% CI -0.34 to -0.01; SE 0.09).Web-based interventions appear to be as effective as print-based interventions. Both modes might help older individuals remain or become active and experience fewer depression symptoms, especially if they feel younger.German Registry of Clinical Trials DRKS00010052 (PROMOTE 1); https://tinyurl.com/nnzarpsu and DRKS00016073 (PROMOTE 2); https://tinyurl.com/4fhcvkwy.RR2-10.2196/15168.
BACKGROUND Physical activity (PA) is associated with health benefits such as fewer depressive symptoms. Little is known about whether and how web- and print-based PA interventions work in comparison to a waiting list control group, especially in older individuals. OBJECTIVE Are interventions delivered in a web- or print mode effective with regard to self-reported PA, stage of change, social-cognitive determinants of PA, and feelings of loneliness and symptoms of depression? Is subjective age a mediator and stage of change a moderator of the effect? METHODS n=589 and n=242 older adults 60+ years were recruited and allocated to a print-based or a web-based intervention or assigned to a waiting list control group (WLCG) within two community-based intervention trials over 10 weeks. Missing value imputation using an Expectation Maximization algorithm was applied. Pooled frequency analyses, MANOVA and moderated mediation analyses were conducted. RESULTS Among the 91 individuals not meeting the endurance training recommendation regarding PA based on self-report, more individuals became active if they were exposed to the web-based intervention (47 out of 59=79.7%) or received the print-based intervention (20/25=80.0%) vs. WLCG (5/7=71.4%; difference was not significant with Chi²(df=2)=0.273, p=.872). Of the 630 individuals meeting the recommendation regarding PA prior to the study, more individuals remained active if they were exposed to the web-based intervention (396/411=96.4%) or WLCG (141/150=94.0%) compared to the ones receiving the print-based intervention (63/69=91.3%). A significant difference was observed favoring the two intervention groups over and above the WLCG with F(19, 701)= 4.778; p<.001; Eta²=.098 and a significant interaction of time and group with F(19, 701)= 2.778; p<.001; Eta²=.070 for the predictors of behavior. The effect of the interventions on subjective age, loneliness and symptoms of depression revealed that both between-groups effects (F(3, 717)=8.668; p<.001; Eta²=.018) and the interaction of group and time were significant (F(3, 717)=6.101; p<.001; Eta²=.025). Both interventions had a significant direct effect on symptoms of depression in comparison to WLCG: WEBc’-path=-0.86 [-1.58, -0.13], SE=0.38; PRINTc’-path=-1.96 [-2.99, -0.92], SE=0.53 (validating the previous analyses). Furthermore, subjective age showed a significant effect on symptoms of depression: Sageb-path=0.14 [0.05, 0.23], SE=0.05. An indirect effect of the intervention on symptoms of depression via subjective age was only present for participants who were in actor stage and received the web-based intervention: WEBab-path=-0.14 [-0.34, -0.01], SE=0.09. CONCLUSIONS The web-based intervention appears to be as effective as the print-based intervention. Both modes of delivery might help older individuals to remain or become active: Therefore, they may benefit in terms of successful aging and may have fewer symptoms of depression. CLINICALTRIAL German Registry of Clinical Trials, 11 July 2016, number: DRKS00010052 (PROMOTE I) & German Registry of Clinical Trials, 10 January 2019, number: DRKS00016073 (PROMOTE II) INTERNATIONAL REGISTERED REPORT RR2-10.2196/15168
