Benefits of Substituting Sitting with Standing and Walking in Free-Living Conditions for Cardiometabolic Risk Markers, Cognition and Mood in Overweight Adults

Abstract

Background: We investigated whether substituting sitting with standing and self-perceived light walking in free-living conditions would improve cardiometabolic risk factors, mood, and cognition in overweight/obese adults.Methods: In a randomized, cross-over study, 24 (m/f: 13/11) sedentary overweight/obese participants (64 ± 7 years, BMI 29 ± 2 kg/m2) followed two activity regimens of each 4 days in free-living conditions: “Sit”: sitting 13.5 h/day, standing 1.4 h/day, self-perceived light-intensity walking 0.7 h/day; for “SitLess” these activities lasted 7.6, 4.0, and 4.3 h/day, respectively. Meals were standardized and physical activity was assessed by accelerometry (activPAL). Insulin sensitivity (expressed as Matsuda-index based on an oral glucose tolerance test), circulating lipids, blood pressure, mood (pleasantness and arousal), and cognition were assessed on the morning after the activity regimens. Quality of life and sleep were assessed on the last day of the activity regimens.Results: We observed that AUC (0–190 min) for insulin decreased by 20% after SitLess vs. Sit [10,125 (656) vs. 12,633 (818); p = 0.006]. Insulin sensitivity improved by 16% after SitLess vs. Sit [Matsuda-index, mean (SEM): 6.45 (0.25) vs. 5.58 (0.25) respectively; p = 0.007]. Fasting triglycerides, non-HDL-cholesterol, and apolipoprotein B decreased by 32, 7, and 4% respectively, whereas HDL-cholesterol increased by 7% after SitLess vs. Sit (all p < 0.01). Diastolic blood pressure was lower after SitLess vs. Sit (p < 0.05). Pleasantness (as one marker of mood status) after the oral glucose tolerance test was higher after SitLess vs. Sit (p < 0.05). There was no significant difference between regimens for cognition, quality of life and sleep.Conclusions: Reducing sitting time in free-living conditions markedly improved insulin sensitivity, circulating lipids, and diastolic blood pressure. Substituting sitting with standing and self-perceived light walking is an effective strategy to improve cardiometabolic risk factors in overweight/obese subjects.

Sit less or exercise more?

“…In line with earlier studies [32-34, 102, 141] substituting sitting with LPA resulted in marked improvements in insulin sensitivity and lipid parameters in the pooled analysis of our experiments, as also reported for each of the individual studies previously [82,98,136]. Structured MVPA did not result in significant improvements in insulin sensitivity and most lipid variables.…”

“…Three counterbalanced randomised cross-over studies with comparable methods were carried out in which the subjects served as their own controls. The methods have been described previously in more detail [82,98,136]. The 'normal weight study' included healthy subjects without obesity (BMI 18-30 kg/m 2 ), the 'overweight study' and the 'diabetes study' included subjects with overweight/obesity (BMI of 25-35 kg/m…”

“…Exclusion criteria included more than 2.5 h/week of moderate-to-vigorous exercise based on selfreport, diseases that interfered with physical activity participation, alcohol abuse and in the subjects without diabetes drugs that interfered with insulin metabolism. A more detailed description of the in-and exclusion criteria has been described earlier [82,98,136].…”

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

“…The exclusion of studies with "free living" protocols might affect the results. However, when free-living trials that did not use strictly controlled laboratory protocols [70,[74][75][76] were included in the meta-analyses the results and interpretation were not qualitatively substantively altered. For example when comparing EE matched PA breaks with continuous exercise, the SMD for glucose measures would have changed from − 0.26 (95% CI − 0.49 − 0.03, p = 0.03) to − 0.23 (95% CI − 0.41, − 0.05, p = 0.01).…”

“…Duvivier et al [74][75][76], and Blankenship [70] were not included in the meta-analysis as the PA breaks protocol were not clearly stated, and free-living designs were used; however, they were included in the narrative summary ( Table 2). All but one [77] study had participants randomised into crossover trial conditions.…”