Background While weekend warrior (WW) physical activity (PA) pattern has been associated with cardiovascular benefits, most existing evidence is based on self-reported PA. Evidence using harmonized, thigh-worn accelerometry to examine associations between the weekend warrior phenotype and comprehensive cardiometabolic profiles remains limited. Methods We pooled harmonized individual-participant data from six cohorts in the Prospective Physical Activity, Sitting and Sleep (ProPASS) Consortium. In this cross-sectional analysis, participants were classified as inactive (