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

Background and aims: 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 behaviours performed in combination on arterial stiffness, a marker of cardiovascular health, is 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. Methods: Using a randomized crossover design, thirteen 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. Results: cfPWV increased significantly more following the high-fat (mean difference [MD]= 0.59 m·s-1) when compared to the low-fat (MD= 0.2 m·s-1) meal, with no change in faPWV in either condition. The af-SG significantly decreased (worsened) (ηp2= 0.569) overtime in high and low-fat conditions (ratio= 0.1 and 0.1 respectively). Superficial femoral PWVβ significantly increased over time in high- and low-fat conditions (ηp2= 0.321; 0.8 and 0.4 m·s-1 respectively). A significant interaction found that triglycerides increased over time in the high fat trial only (ηp2= 0.761). There were no significant changes in blood pressures. Conclusions: Consuming a high-fat meal prior to 180 min of uninterrupted sitting augments markers of cardiovascular disease risk more than sitting following a low-fat meal