Purpose: This study aimed to examine how accelerometer-assessed physical activity accumulation patterns (e.g., is activity performed daily or only 1 or 2 d·wk or is activity accrued in bouts) may affect the association with mortality.
Methods: Adults (N = 3438), age 40 yr and older, who wore an accelerometer (ActiGraph 7164), were drawn from the longitudinal follow-up of the National Health and Nutritional Examination Survey (2003-2006), a population-based survey of the United States. Accelerometer-assessed moderate-to-vigorous physical activity (MVPA) was described by activity patterns. Participants engaging in the majority of their activity on only 1 or 2 d·wk· were classified as "weekend warriors." Activity bouts were defined as a period of at least moderate intensity lasting at least 10 min. Bout characteristics included bout frequency and length. Mortality was assessed through National Death Index matching through 2013. Mortality rates were compared among groups with different activity patterns.
Results: Over an average follow-up of 77.4 months, 394 deaths occurred. Compared to participants with <37.5 min of MVPA per week, those with greater amounts of activity had a 60% to 69% mortality rate reduction after adjusting for relevant covariables. Similar risk reductions were found when contrasting weekend warriors with those who were more frequently active. An increase of one MVPA bout per week was associated with a 13% increased mortality rate. Bout duration was not associated with mortality.
Conclusion: Physical activity is associated with decreased mortality rate, even among those who are active 1 or 2 d·wk.