Physical activity interventions in low socioeconomic status populations: A focus on mental contrasting with implementation intentions

Abstract

Socioeconomic status has been shown to be an important determinant of physical activity levels in adults. On average, low socioeconomic status populations are reported to be less physically active compared to more affluent members of society. In addition to a lack of effective physical activity interventions targeting low socioeconomic status populations, no studies in this population have applied the self-regulation strategy, mental contrasting with implementation intentions, which has been to increase physical activity levels in the general population. This Masters thesis sought to investigate the effectiveness of interventions aimed at increasing physical activity in low socioeconomic status adults with a focus on self-regulation and physical activity monitors. In the first study, a systematic review was conducted to assess the effectiveness of pedometer- or accelerometer- based interventions aimed at increasing physical activity in low socioeconomic status adults. After screening and verification, a total of three studies were included. Due to the low number of studies included in this review and the multicomponent nature of the three interventions, it was impossible to attribute any changes in physical activity to pedometers or accelerometers alone. In the second study, a 12-week pilot randomised controlled trial was used to investigate the feasibility and efficacy of the self-regulation strategy, mental contrasting with implementation intentions, in inactive low socioeconomic adults. Thirty-two participants were randomised to either a mental contrasting with implementation intentions intervention condition or a control condition. The main outcome measures were (i) recruitment and retention rates, (ii) self-reported minutes of physical activity per week and, (iii) combined weekly accelerometer plus diary-reported physical activity. Participants in the mental contrasting with implementation intentions condition and control condition both significantly increased self-reported physical activity after 12-weeks. No significant between-group differences were seen at 12-weeks. This pilot randomised controlled trial demonstrated that it is feasible to conduct a physical activity intervention in low socioeconomic adults that applies mental contrasting with implementation intentions. Findings from the pilot study suggest that a mental contrasting with implementation intentions intervention can increase physical activity levels in a low socioeconomic status sample. The small sample size made it difficult to reach firm conclusions regarding the strategy’s effectiveness. More research is needed to provide further insight into the strategy’s effectiveness in this population. The implications of the two studies contained within the current thesis are that both accelerometer and mental contrasting with implementation intention interventions hold promise for increasing physical activity levels in low SES populations - either together or separately. Moreover, interventions set within behaviour-change frameworks in low SES groups may elicit equivalent increases in physical activity as observed in studies focused on higher SES populations. Collectively, this Masters thesis assessed the effectiveness of pedometer- or accelerometer- based interventions in low socioeconomic populations concluding that a physical activity intervention applying mental contrasting with implementation intentions are feasible and may be effective in inactive low socioeconomic adults.