A Study to Assess the Impact of a Multicomponent Intervention to Reduce Prolonged Sitting in the Workplace

There is increasing evidence to demonstrate that excessive and unhealthy patterns of sedentary behaviour can increase the risk of a range of health problems,independent to levels of physical activity. Increasingly, people are employed in low activity occupations with office workers being identified as one of the most sedentary roles. Small scale studies using prompts to remind office workers to stand have shown promising results, as well as representing a low-cost solution for employers. This study builds upon a recent pilot study investigating the impact of prompts delivered via Microsoft Outlook, on the sedentary behaviour of office workers.

Developed in accordance with the Medical Research Council framework for designing multi-component interventions this study utilises Social Cognitive Theory (SCT) as a theoretical basis. SCT describes the complex interaction between individuals and their environment. The influence of the office environment on sedentary behaviour is clearly illustrated by differences in people's sitting patterns inside and outside of working hours . Behavioural change techniques linked to the constructs of SCT have also been shown to have a positive impact on sedentary behaviour, namely education, goal setting and feedback. Participants in this study will therefore receive education on the benefits of breaking their sitting, tips on how to achieve this, and feedback on their baseline sitting behaviour. This study will test the impact of these techniques on sitting time and patterns, and also track their influence on the different constructs of SCT and individuals' readiness to change by measuring these at time points throughout the intervention. To address the fact that sitting at work may not be a conscious decision, but performed out of habit, half of participants will also receive prompts reminding them to stand. The same prompts will be used as in the pilot study, but the addition of an extra activity monitoring period will enable us to ascertain whether the impact of prompts diminishes during the intervention period.

This study will aim to recruit 60 desk-based office employees via email invitation. Volunteers will be screened using inclusion/exclusion criteria and asked to provide signed consent. Sitting will be de-emphasised in the participant information sheet, and other documentation used at recruitment, in order to minimise any impact on baseline activity measurements. Cluster randomisation will be used to split participants into two equal groups (Group 1 n=30, group 2 n=30) based on their physical location within the office(s) in order to minimise contamination between groups. Randomisation software will be used to allocate groups on www.randomisation.com. Baseline measurement for all participants will consist of completion of questionnaires and activity monitoring as follows:

1. Questionnaires:

• Q1: Demographic data - to obtain basic information on participants
• Q2: Stage of change questionnaire - measuring readiness to change
• Q3: Social cognitive theory questionnaire - measuring key constructs of SCT

2. Activity monitoring: