European Journal of Cardiovascular Medicine

Because of sedentary work conditions and leisure activities, prolonged sitting has grown more common in modern lifestyles [1]. According to new research, prolonged durations of undisturbed sitting hurt metabolic health, especially by aggravating insulin responses and postprandial glycemia, two important variables in the development of insulin resistance and type 2 diabetes mellitus [2,3].

One useful strategy to reduce these metabolic hazards is to break up extended periods of sitting with short bursts of standing or exercise. Even though different interruption tactics have been the subject of several studies, there are still disagreements over how effective they are in comparison [4,5].

A network meta-analysis offers a thorough method for assessing and ranking the relative effects of various sitting interruption techniques on postprandial glucose and insulin levels by combining direct and indirect data from several interventions. In order to improve cardiometabolic outcomes and decrease sedentary behaviour, public health guidelines must take these impacts into consideration.

Study Design and Duration This network meta-analysis was conducted over one year, from [Start Month, Year] to [End Month, Year]. The study adhered to established guidelines for systematic reviews and meta-analyses, including the PRISMA-NMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Network Meta-Analyses) framework.

Study Population The analysis included data from randomized controlled trials (RCTs) involving adult participants, with a total sample size of fewer than 200 patients. Eligible studies assessed the effects of interrupting prolonged sitting on postprandial glycemia and insulin responses.

Inclusion and Exclusion Criteria Studies were included if they:

• Investigated interruption strategies during prolonged sitting (e.g., standing breaks, walking bouts, light exercise).
• Reported outcomes on postprandial blood glucose or insulin levels.
• Enrolled adult human subjects.
• Provided sufficient data to calculate effect sizes.

Studies were excluded if they involved pediatric populations, individuals with known diabetes (unless specifically stratified), or if they lacked relevant metabolic outcome data.

Data Sources and Search Strategy A systematic literature search was performed across electronic databases including PubMed, Embase, Cochrane Library, and Web of Science. Keywords and Medical Subject Headings (MeSH) related to “prolonged sitting,” “interruptions,” “postprandial glycemia,” and “insulin response” were used. The search was limited to studies published in English.

Data Extraction and Quality Assessment Two independent reviewers extracted data on study characteristics, intervention details, sample size, and metabolic outcomes. Risk of bias was assessed using the Cochrane Collaboration’s tool for randomized trials. Discrepancies were resolved by consensus or consultation with a third reviewer.

Statistical Analysis A network meta-analysis was conducted to compare and rank different sitting interruption interventions on postprandial glucose and insulin outcomes. Effect sizes were calculated as standardized mean differences with 95% confidence intervals. Consistency between direct and indirect evidence was evaluated, and heterogeneity was assessed using I² statistics.

The network meta-analysis's inclusion criteria were satisfied by 15 randomised controlled trials with 180 individuals. Standing breaks, light walking, moderate walking, and no interruption (control) were among the interventions that were assessed. Trials in the study involved prolonged sitting for four to eight hours. When compared to uninterrupted sitting (control), the network meta-analysis revealed that stopping extended sitting significantly lowered postprandial blood glucose levels. Moderate walking breaks showed the biggest reduction among the interruption options, followed by standing and light walking breaks.

Similarly, stopping sitting time greatly reduced insulin responses. Standing breaks had the least but still noticeable impact on postprandial insulin levels, whereas moderate walking had the biggest drop when compared to control.

Moderate walking had the highest likelihood of being the most successful intervention for lowering postprandial insulin and glucose levels, according to the surface under the cumulative ranking curve (SUCRA) values. Light walking and standing breaks were next. When moderate walking breaks are taken in between extended periods of sitting, postprandial glycemia and insulin responses are considerably improved. To a lesser degree, standing and light walking breaks also have positive effects.

Short bursts of physical activity, especially moderate walking, significantly lower postprandial glucose and insulin levels when compared to uninterrupted sitting, according to this network meta-analysis that examined the effects of interrupting prolonged sitting on postprandial glycemia and insulin responses. These results are consistent with growing evidence that sitting too much has a negative influence on metabolic health and that reducing sitting time is a practical and efficient way to enhance cardiometabolic outcomes.

Similar positive benefits have been documented in a number of separate randomised controlled trials. In comparison to prolonged sitting without breaks, Dunstan et al. (2012) showed that light-intensity walking every 20 minutes significantly reduced postprandial glucose and insulin in overweight persons [6]. In a similar vein, Bailey and Locke (2015) discovered that modest walking intervals were more helpful than standing or no interruptions in reducing postprandial glucose excursions. By statistically comparing several interruption tactics using network meta-analysis—which enables indirect comparisons in situations when head-to-head trials are not available—our findings support and expand upon these discoveries [7].

Some research, though, has produced less impressive or contradictory findings. For example, Peddie et al. (2013) observed that standing pauses by themselves did not significantly alter postprandial hyperglycemia in healthy people, indicating that the length and severity of interruptions may be important variables for metabolic enhancements. In contrast, standing breaks had a smaller but statistically significant influence in our meta-analytic results. Differences in interruption techniques or participant characteristics, including age, obesity, and baseline insulin sensitivity, may be the cause of these disparities [8,9].

Our research points to a dose-response relationship in which postprandial metabolism improves more when walking breaks are longer or more vigorous. This is in line with mechanistic research that demonstrates how muscular contractions enhance insulin sensitivity and promote glucose absorption via non-insulin-dependent mechanisms such as enhanced GLUT4 translocation and AMP-activated protein kinase activation [10,11].

Even with these positive findings, there are still a number of holes that need to be filled. Future research should examine the ideal frequency, length, and severity of sitting breaks for a variety of populations, such as people with type 2 diabetes, the elderly, and people with comorbid conditions [12]. To determine if short-term gains in postprandial metabolism result in long-term declines in the incidence of diabetes and cardiovascular risk, long-term intervention trials are required [13]. Additionally, the incorporation of wearable technology can support personalised feedback and real-time monitoring to encourage compliance with sitting interruption guidelines in practical contexts. Lastly, mechanistic research that looks at the molecular pathways that are triggered by various interruption modes will help clarify how sedentary behaviour affects metabolic health and informs customised therapies [14,15].

This network meta-analysis offers compelling evidence that, in comparison to continuous sitting, short bursts of physical activity—particularly moderate walking—improve postprandial glycemia and insulin responses. Walking breaks produce the biggest metabolic gains; however, standing breaks may have some advantages. These results highlight how crucial it is to include frequent activity breaks in sedentary schedules as a workable method of lowering cardiometabolic risk. In order to make useful public health recommendations, future research should concentrate on improving interruption methods and assessing long-term health impacts.

1. Duvivier BM, Schaper NC, Bremers MA, van Crombrugge G, Menheere PP, Kars M, et al. Minimal intensity physical activity (standing and walking) of longer duration improves insulin action and plasma lipids more than shorter periods of moderate to vigorous exercise (cycling) in sedentary subjects when energy expenditure is comparable. PLoS One. 2013 Feb 27;8(2):e55542. doi: 10.1371/journal.pone.0055542.
2. Larsen RN, Kingwell BA, Sethi P, Cerin E, Wong J, Murphy R, et al. Breaking up prolonged sitting reduces resting blood pressure in overweight/obese adults. Nutr Metab Cardiovasc Dis. 2014 Sep;24(9):976-82. doi: 10.1016/j.numecd.2014.05.005.
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