The purpose of this pragmatic trial is to determine the implementation potential of three movement break doses (every 30, 60, or 90 min) under real-world conditions. The main questions it aims to answer are:

• What is the feasibility, acceptability, appropriateness, and compliance to the tested movement break doses under real-world conditions?
• What is the effectiveness of the movement break doses on improving mood, fatigue, and work performance?
• What are the barriers of and facilitators to taking movement breaks across population subgroups (age group, sex, race/ethnicity, employment status, employment setting, and occupation).

Researchers will compare differences in the primary (implementation metrics), secondary (mood, fatigue, and work performance), and exploratory (barriers/facilitators) outcomes across the three trial arms (movement breaks every 30, 60, or 120 minutes).

Participants will:

• Take movement breaks (5 minutes of walking at a self-selected pace) daily according to their dose condition (every 30, 60, or 90 minutes) for two consecutive weeks.
• Complete daily surveys to report compliance, barriers/facilitators, and mood/fatigue/work performance.
• Complete a survey battery at the end of the study to report implementation potential, rank/rate barriers and facilitators, and evaluate mood/fatigue/work performance.

To address the study aims, the investigator will recruit 50,000 adults and will conduct a dosing study that concurrently tests three movement break doses. Participants will complete a 7-day baseline period to assess normal durations of sedentary behavior and movement, followed by a 2-week period during which they will be select a movement break dose to implement in their everyday life for the duration of the program. The break frequency x duration combination will include 5 minute every 30 minutes, 5 minutes every 60 minutes, and 5 minutes every 120 minutes. Work and leisure behaviors, mood, fatigue, and barriers/facilitators will be assessed via survey at enrollment, as well as via daily surveys during the baseline and intervention monitoring periods.

U.S. adults spend on average ~11-12 h/day sedentary. Accordingly, the phrase "sitting is the new smoking" has been used to describe an epidemic of developed nations. Daily sedentary time is strongly associated with risk for cardiovascular disease (CVD) morbidity and mortality, irrespective of moderate-vigorous physical activity (MVPA). As such, the 2018 Physical Activity Guidelines for Americans, have expanded beyond promoting MVPA and now also advocate for reductions in sedentary time. These recommendations, however, are very general ("sit less, move more") due to a paucity of data to inform more quantitative recommendations. To inform more specific guidelines, both the 2018 Physical Activity Guidelines Advisory Committee Scientific Report and a scientific advisory on sedentary behavior from the American Heart Association (AHA) have identified a critical research need for studies that compare different doses of reducing sedentary time on health outcomes and evaluate the barriers to real-world implementation of sedentary time reduction strategies. Such studies were deemed to be critical for development of evidence based sedentary behavior guidelines. The proposed study will address this major evidence gap and provide evidence to inform the feasibility of specific, quantitative movement break sedentary behavior recommendations.

Research has implicated sedentary time accrued in prolonged, uninterrupted bouts (e.g., sitting for hours at a time) as potentially the most hazardous form of sedentary behavior; suggestive that regularly breaking up sedentary time with bouts of activity may be an important adjunct to existing physical activity guidelines. Although these data inform which sedentary behavior feature to target, they provide little to inform quantitative guidelines. Thus, only general recommendations to "sit less, move more" have been proposed without specific, actionable targets. The investigator's latest laboratory-based research has documented quantitative guidance regarding (1) How frequent should periods of prolonged sedentary time be interrupted? and (2) What is the appropriate duration of these breaks in sedentary time? However, it is unclear how feasible and acceptable these quantitative recommendations (i.e., taking a walking break every half hour for 5 minutes) are. Moreover, the barriers to and facilitators of successfully implementing breaks in sedentary time during the day are largely unknown.

Primary Aim: To determine the feasibility, acceptability, and appropriateness (i.e., the implementation potential) of and compliance to three movement break doses (every 30, 60, or 120 minutes) under real world conditions.

Secondary Aim: To determine the effect of various movement break doses on mood, fatigue, and work performance.

Exploratory Aim: The successful implementation of movement breaks into mainstream society relies on an understanding of common facilitators and barriers to movement breaks faced by the public across a vast array of population subgroups. This study will map barriers to and facilitators of movement breaks by age group (young, middle-aged, and older adults), sex, race/ethnicity, employment status (full-time, part-time, retired, not working), employment setting (remote, in-person, hybrid), and occupation type.

Excessive sedentary time is highly prevalent in developed nations and linked to increased CVD risk. No evidence-based recommendations exist on how people should break up sedentary time. Evaluating the implementation potential of doses (in frequency and duration) of a movement break intervention that yields improvements across several health indices and establishing barriers/facilitators to movement breaks across population subgroups could have a powerful impact on public health by establishing a recommended movement break dose for future randomized trials and guidelines and laying the foundation to optimize future movement break interventions that address population barriers.

Inclusion Criteria:

• 18 years of age or older
• English speaking
• Access to a smart phone with a data and text messaging plan

Exclusion Criteria:

• Recent history of bone, joint, or soft tissue injury that would be worsened by exercise
• Chest pain at rest, during activities of daily living, or with movement
• Instructions from a physician requiring supervised exercise