Abstract
Current conventions, partly derived from self-reported data, typically equate 1 minute of vigorous physical activity (VPA) to 2 minutes of moderate physical activity (MPA). Using accelerometer-derived intensity classification in 73,485 UK Biobank participants (mean follow-up: 8.0 [1.0] years), we assess the equivalence of light activity (LPA) and MPA to 1 minute of VPA for all-cause (ACM) and cardiovascular (CVD) mortality, major adverse cardiovascular events (MACE), type 2 diabetes, and cancer outcomes. For a standardised 5%-35% risk reduction, the median MPA equivalent per minute of VPA is 4.1 (ACM, 95% CI: 4.1-4.2), 7.8 (CVD mortality, 7.7-8.0), 5.4 (MACE, 5.3-5.5), 9.4 (type 2 diabetes, 9.3-9.6), and 3.5 (cancer mortality, 3.4-3.5) minutes. For non-cancer outcomes, the median LPA equivalent per 1 minute of VPA ranges from 53 (ACM) to 94 minutes (type 2 diabetes), reflecting generally weaker dose-response curves of LPA with all outcomes. These findings indicate a substantial departure from self-reported estimates and support integrating device-based equivalence into guidelines and wearables.