Physical activity guidelines recommend that adults accumulate at least 150 min of moderate-to-vigorous physical activity (MVPA) per week in bouts of at least 10 min. However, sporadic MVPA contributes significantly to total physical activity and may also affect health. The study objective was to determine, within adults age 18 to 64 yr, whether MVPA accumulated in bouts is more strongly associated with metabolic syndrome (MetS) than an equivalent volume of MVPA accumulated sporadically.