Purpose: Frequent consumption of high-fat meals and prolonged sedentary time are prevalent lifestyles that have been associated with an increased risk of vascular and metabolic complications. This study evaluated the acute effects of interrupting prolonged sitting with stair climbing on vascular and metabolic function after a high-fat meal.
Methods: In a randomized, cross-over trial, 12 healthy adults (age: 23.5 ± 2.9 years) consumed a high-fat meal, followed by either 1) a 4-h uninterrupted sitting (sitting trial) or 2) a 4-h sitting interrupted with a 5-min stair climbing (average intensity: 66% of heart rate reserve) every hour (interrupted trial). Plasma triglyceride and glucose concentrations, as well as popliteal artery blood flow and shear rate were assessed at baseline and every hour after a high-fat meal, whereas brachial artery flow-mediated dilation was assessed at baseline and again at the end of each trial.
Results: Plasma triglyceride and glucose concentrations increased after a high-fat meal and returned to baseline at the end of both trials. Following a high-fat meal, brachial artery flow-mediated dilation decreased in the sitting trial, but not in the interrupted trial (sitting trial: 9.65 ± 2.63% to 7.84 ± 2.36%; interrupted trial: 9.41 ± 2.61% to 10.34 ± 3.30%, p = 0.009 for interaction). Compared with the sitting trial, the interrupted trial improved popliteal blood flow and shear rate (p = 0.004 and p = 0.008 for interaction, respectively).
Conclusions: These findings suggest that interrupting prolonged sitting with stair climbing may be an effective lifestyle strategy to prevent against vascular dysfunction that might occur as a result of prolonged sitting after consuming a high-fat meal in young healthy adults.
Keywords: High-fat meal; Interrupting prolonged sitting; Stair climbing; Vascular function.