Interventions for promoting physical activity and reducing sedentary time among people aged 55 years and older: an overview of systematic reviews.

A total of 21 systematic reviews were included, with the majority being of low or critically low methodological quality.

• 21 systematic reviews were identified from searches of five electronic databases (PubMed, CINAHL, Scopus, Cochrane and SportDiscus)
• 17 of the 21 included reviews conducted meta-analyses
• Seven reviews were of moderate quality, 11 were of low quality, and three were of critically low quality as assessed using the AMSTAR-2 tool
• Reviews focused on interventions for adults aged 55 years or older

Technology-based interventions demonstrated consistent evidence of significant increases in physical activity among older adults.

• Six of seven meta-analyses of technology-based interventions demonstrated significant increases in physical activity
• All five meta-analyses examining step counts reported significant improvements
• Four of five meta-analyses showed significant benefits for MVPA (moderate to vigorous physical activity)
• Two meta-analyses reported inconsistent findings on sedentary time for technology-based interventions

Exercise and behavioural interventions showed inconsistent effects on physical activity among older adults.

• Six meta-analyses of exercise and behavioural interventions examined physical activity after 12 months
• Two meta-analyses reported a significant difference in physical activity after 12 months
• Two meta-analyses found no significant difference in physical activity
• Two meta-analyses presented mixed findings across subgroups
• Only one meta-analysis reported an effect on sedentary time and observed no significant improvement

The authors' own meta-analyses partially supported the findings from the included systematic reviews.

• Meta-analyses of original studies were conducted to explore the effect of different types of intervention on outcomes in the short and intermediate term
• Results from the authors' meta-analyses were described as 'partially supported' by the results from included reviews
• Analyses were grouped by intervention type (e.g., technology-based, exercise and behavioural) and outcome measure (e.g., total physical activity, step counts, MVPA, sedentary time)

Limited evidence exists examining interventions specifically designed to reduce sedentary time in older adults.

• Physical inactivity and prolonged sedentary behaviours are described as common among older adults, leading to increased risk of chronic diseases and mortality
• Only one meta-analysis of exercise and behavioural interventions reported an effect on sedentary time and observed no significant improvement
• Two meta-analyses of technology-based interventions reported inconsistent findings on sedentary time
• The authors concluded that 'future research targeting sedentary behaviours is needed'