Patterns of Interrupting Prolonged Sitting and Postprandial Triglycerides in East-Asian Young Men with Central Obesity

Abstract

Prolonged sitting is related to an increased risk of morbidity and mortality. In the literature, frequent interruptions to prolonged sitting, e.g., every 30 min of sitting, have been found to be beneficial for cardiometabolic health. Interrupting prolonged sitting less frequently, however, may be preferred due to practical issues. PURPOSE: To examine the acute effect of different frequency of interrupting prolonged sitting on postprandial triglycerides (TG) in young men with central obesity compared with prolonged sitting. METHODS: Twenty-one East-Asian men with central obesity (mean age: 23.24 ± 3.65 years; body mass index: 29.78 ± 3.17 kg·m-2; waist circumference: 98.71 ± 7.08 cm) completed three randomized 7-h laboratory-based trials including 1) a prolonged sitting trial (SIT), 2) 3-min walking every 30 min (3-min) at 3.2 km·h-1, and 3) 6-min walking every 60 min (6-min) at 3.2 km·h-1 separated by 7-14 days washout period. Standardized mixed meals (50% carbohydrate, 30% Fat, and 15% Protein) were provided at 0 and 3 h. Blood samples were collected at -1, 0, 0.5, 1, 2, 3, 3.5, 4, 5, and 6 h. TG concentrations were changed to total area under the curve (tAUC) using the Trapezoidal method. One-way (trial) and two-way (trial × time) ANOVAs with repeated measures were used to compare tAUC value and TG concentrations, respectively. RESULTS: Regarding the tAUC, the main effect of trial (F2, 40 = 4.210, P = 0.022, η2 = 0.174) was significant with 6-min trial (10.58 ± 3.62 mmol·L-1 per 7 h; P = 0.020) being lower than SIT trial (11.83 ± 3.52 mmol·L-1 per 7 h). There were no differences on the 7-h tAUC for TG concentrations between 3-min (11.52 ± 3.47 mmol·L-1 per 7 h; P > 0.05) and SIT trials as well as between 3-min and 6-min trials (both Ps > 0.05). Regarding TG concentrations, the main effect of trial (F2, 40 = 4.448, P = 0.018, η2 = 0.182) was significant with 6-min trial being lower than SIT trial (P = 0.013). The main effect of time was also significant (F9, 180 = 66.589, P < 0.001, η2 = 0.769) with the TG concentrations significantly increased from 1 h to 6 h (all Ps < 0.05) compared with the baseline (the average of TG concentrations between -1 and 0 h). CONCLUSIONS: Interrupting prolonged sitting with 6-min trial elicits a superior benefit on reducing postprandial TG than SIT trial in East-Asian young men with central obesity.