Workplace Intervention to Reduce Sitting Time: a Randomized Clinical Trial.

Workplace Intervention to Reduce Sitting Time, Decrease Musculoskeletal Symptoms, and Improve Cardiometabolic Markers in Sedentary Office Workers: a Randomized Clinical Trial.

The goal of this randomized clinical trial is to determine the effect of the computer prompt to break sitting time in office workers.

The main question is: What is the effect of the computer prompt "Stand Up for Your Health®" plus education on sitting time, musculoskeletal symptoms, cardiometabolic markers, and physical activity in office workers compared with only education? In addition, to determine the level of adherence to the intervention program by identifying barriers and facilitators referred by the participants.

The participants will be divided into two groups, the experimental and the control group. The participants in the experimental group will use the computer prompt on their desktop and receive information about sedentary behaviour, and the control group will receive only information. All participants will wear accelerometers for one week. The musculoskeletal symptoms and cardiometabolic markers will be measured at baseline, 3rd and 6th month.

Sedentary behaviour and physical inactivity are risk factors for noncommunicable diseases related to the work environment. The accumulation of sitting time during the workday is related to musculoskeletal symptoms and worse cardiometabolic indicators.

The purpose of this study is to determine the effect of the "Stand up for your Health®" computer app on sitting time, musculoskeletal symptoms, cardiometabolic markers, and physical activity in office workers. Also, to determine the adherence to the intervention program by identifying barriers and facilitators referred by the participants.

In this 2-arm randomized controlled trial, both groups will be recruited from educational establishments and will be measured at baseline, 3rd, and 6th months. The experimental group will be implementing the "Stand Up for Your Health®" computer app plus educational information, while the control group will only receive educational information.

The same measurements will be completed in both groups during a 6 months follow-up period: sedentary behaviour using the Actigraph accelerometers and the Occupational Sitting and Physical Activity Questionnaire (OSPAQ); musculoskeletal symptoms will be assessed by a pressure pain algometer and the Standardized Nordic Questionnaire of Perception of musculoskeletal Symptoms; and cardiometabolic markers and anthropometric measurements will also be assessed according to protocol.

Inclusion Criteria:

• office workers over 18 years of age,
• Full-time employees (≥35 hours per week);
• Spend most of their workday sitting (> 60%). This will be initially self-reported and used as selection criteria prior to the initial consent and measurement visit. This will be later confirmed using accelerometers;
• Work in the same office place during the week; and
• Able to walk without using an assistive device or requiring the assistance of another person.

Exclusion Criteria:

• Pregnant women;
• Desktop workers using a height-adjustable workstation; and
• Office workers sufficiently active according to WHO criteria.