Reducing prolonged sedentary time using a treadmill desk acutely improves cardiometabolic risk markers in male and female adults

Abstract

This study evaluated the acute effects of interrupting prolonged sitting with an accumulated 2 h of light-intensity walking on postprandial cardiometabolic risk markers. In this randomised crossover trial, 24 participants (twelve males) aged 18-55 years took part in two, 6.5 h conditions: 1) prolonged sitting (SIT) and 2) sitting interrupted hourly with 20 min light-intensity treadmill desk walking at between 1.2-3.5 km/h (INT-SIT). Standardized meals were provided at 0 h and 3 h. Blood samples and blood pressure measures were taken hourly. Statistical analyses were completed using linear mixed models. Postprandial incremental area under the curve responses (mmol/L∙6.5 h) for glucose (4.52 [3.47, 5.56] and 6.66 [5.62, 7.71] for INT-SIT and SIT, respectively) and triglycerides (1.96 [0.96, 2.96] and 2.71 [1.70, 3.71] for INT-SIT and SIT, respectively) were significantly lower in INT-SIT than SIT. Mean systolic and diastolic blood pressure responses were lower by 3% and 4%, respectively, in INT-SIT than SIT (P < 0.05). There was no significant condition x sex interaction effect for any outcomes (P > 0.05). These findings suggest that interrupting sitting with an accumulated 2 h of light-intensity walking acutely improves cardiometabolic risk levels in males and females compared with prolonged sitting.

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

“…6,11). Conversely, 2 studies [46,72] reported no sex interactions for any outcomes when sitting was interrupted by light or moderate walking. Both sex specific PA break protocols or the underlying mechanisms, such as oestrogen levels [48][49][50][51], responsible for any possible sex divergent metabolic responses to PA breaks could be avenues for further research.…”

Acute effects of breaking up prolonged sedentary time on cardiovascular disease risk markers in adults with paraplegia

“…This is in agreement with studies in healthy able-bodied individuals. 15,35 However, reductions in triglyceride and blood pressure levels have been observed in other studies with healthy 36,37 and overweight/ obese adults. 17 One study in which triglycerides were attenuated over a single day used larger volumes of physical activity compared to the present study (ie, 20 minutes of light-intensity walking every hour).…”

“…17 One study in which triglycerides were attenuated over a single day used larger volumes of physical activity compared to the present study (ie, 20 minutes of light-intensity walking every hour). 37 It is thus possible that the lower energy expenditure and localized muscular contractions were insufficient to yield a change in the present study. Other studies that have demonstrated attenuation in postprandial triglycerides were in response to a test meal provided the day after breaking up sitting.…”

Cardiometabolic Response to a Single High-intensity Interval Exercise Session Versus Breaking up Sedentary Time with Fragmented High-intensity Interval Exercise

“…Other studies have failed to observe a reduction in postprandial insulin [3,5,27] or change in the insulin-signalling pathway [6] in response to 2 min of light or moderate-intensity walking every 20 min over a single day, although these studies similarly were not powered to detect changes in these outcomes. Postprandial insulin reductions occurred in response to 2-5 min of light or moderate-intensity PA every 20-30 min and 20 min of light walking every hour in other studies that included larger sample sizes [10,14,20,30,32]. Future studies should thus be adequately powered to detect changes in postprandial glucose and insulin to provide a greater understanding of the mechanistic regulation in response to interrupting sedentary time.…”