Central and peripheral arterial stiffness responses to uninterrupted prolonged sitting combined with a high-fat meal: a randomized controlled crossover trial

Independently, prolonged uninterrupted sitting and the consumption of a meal high in saturated fats acutely disrupt normal cardiovascular function. Currently, the acute effects of these behaviors performed in combination on arterial stiffness, a marker of cardiovascular health, are unknown. This study sought to determine the effect of consuming a high-fat meal (Δ = 51 g fat) in conjunction with prolonged uninterrupted sitting (180 min) on measures of central and peripheral arterial stiffness. Using a randomized crossover design, 13 young healthy males consumed a high-fat (61 g) or low-fat (10 g) meal before 180 min of uninterrupted sitting. Carotid-femoral (cf) and femoral-ankle (fa) pulse wave velocity (PWV), aortic-femoral stiffness gradient (af-SG), superficial femoral PWV beta (β), and oscillometric pulse wave analysis outcomes were assessed pre and post sitting. cfPWV increased significantly more following the high-fat (mean difference [MD] = 0.59 m·s⁻¹) meal than following the low-fat (MD = 0.2 m·s⁻¹) meal, with no change in faPWV in either condition. The af-SG significantly decreased (worsened) (η_p² = 0.569) over time in the high- and low-fat conditions (ratio = 0.1 and 0.1, respectively). Superficial femoral PWV_β significantly increased over time in the high- and low-fat conditions (η_p² = 0.321; 0.8 and 0.4 m·s⁻¹, respectively). Triglycerides increased over time in the high-fat trial only (η_p² = 0.761). There were no significant changes in blood pressure. Consuming a high-fat meal prior to 180 min of uninterrupted sitting augments markers of cardiovascular disease risk more than consuming a low-fat meal prior to sitting.