Interrupting Sitting Time with Regular Walks Attenuates Postprandial Triglycerides

Abstract

We compared the effects of prolonged sitting with the effects of sitting interrupted by regular walking and the effects of prolonged sitting after continuous walking on postprandial triglyceride in postmenopausal women. 15 participants completed 3 trials in random order: 1) prolonged sitting, 2) regular walking, and 3) prolonged sitting preceded by continuous walking. During the sitting trial, participants rested for 8 h. For the walking trials, participants walked briskly in either twenty 90-sec bouts over 8 h or one 30-min bout in the morning (09:00-09:30). Except for walking, both exercise trials mimicked the sitting trial. In each trial, participants consumed a breakfast (08:00) and lunch (11:00). Blood samples were collected in the fasted state and at 2, 4, 6 and 8 h after breakfast. The serum triglyceride incremental area under the curve was 15 and 14% lower after regular walking compared with prolonged sitting and prolonged sitting after continuous walking (4.73±2.50 vs. 5.52±2.95 vs. 5.50±2.59 mmol/L∙8 h respectively, main effect of trial: P=0.023). Regularly interrupting sitting time with brief bouts of physical activity can reduce postprandial triglyceride in postmenopausal women.

Effects of Interrupting Prolonged Sitting with Physical Activity Breaks on Blood Glucose, Insulin and Triacylglycerol Measures: A Systematic Review and Meta-analysis

“…However, this is as yet untested experimentally. Additionally, the duration of individual discrete sitting bouts varied, for example 1.5 min of brisk walking every 15 min [20] or every 30 min [62]. Interestingly, when participants had their sleep restricted, PA breaks did not attenuate post-prandial glucose measures compared to sitting.…”

“…Physical activity (PA) breaks in sitting were also more effective than one continuous bout of exercise on glucose. Nonetheless because this review only included five studies on glucose, published between 2011 and 2014, some relevant earlier studies [7][8][9][10][11][12] and more recent studies [13][14][15][16][17][18][19][20][21][22] might have been omitted or missed. There was no date restriction in Benatti et al [23] but no meta-analysis was performed.…”

“…It is unclear if the number, duration, intensity, amount and modality of PA breaks within a period of prolonged sitting, and the total duration of the sitting bout, are mediators in the metabolic responses to sitting, with only one study investigating and reporting that such variables did not affect glucose outcomes [69]. Most currently researched modalities involve light to moderate walking or running [7,8,13,20,21,46,68]. To date, only Dempsey et al [47] and Hawari et al [78] have examined metabolic responses to simple resistance activities (SRAs) as a means to interrupt sitting.…”

“…Additionally, different sitting periods were used, along with different patterns of PA breaks. Some used 2 day laboratory designs [7,8,11,45], whereas others used 1 day [20,60,62,77]. A free-living protocol over 1 day [70] or 4 days [74,75] was also used.…”

Effects of Aerobic Exercise on Atherosclerotic Risk in Postmenopausal Women

“…The higher level of TG may induce atherosclerosis by changing the structure of LDL and HDL [23]. TG is the most abundant lipid in the human body, and it can be oxidized and decomposed through a series of chemical reactions to provide energy for people during exercise [25]. It is also the mechanism through which exercise training can regulate blood lipids.…”