The effects of acute exposure to prolonged sitting, with and without interruption, on central and peripheral pulse...

Sedentary behavior, specifically an acute bout of prolonged uninterrupted sitting, is associated with heightened cardiovascular disease (CVD) risk, with increased arterial stiffness (AS) being implicated as a principal pathophysiological mechanism. The current systematic review, with meta-analysis, aimed to consolidate the AS response to (1) prolonged uninterrupted sitting and (2) interrupted sitting, as assessed by central and peripheral pulse wave velocity (PWV).

In total, 326 articles were identified, of which 11 and seven met the inclusion criteria for objectives (1) and (2), respectively. Mean differences (MD) and 95% CI were calculated for all trials using a three-level random-effects model, with restricted maximum likelihood (REML) estimation. The amount of heterogeneity was estimated using Cochran's Q and Higgins's I² tests.

(1) Prolonged uninterrupted sitting resulted in a significant increase in carotid-femoral (cf) PWV (MD = 0.184 m/s, 95% CI = 0.098 to 0.270, p < 0.0003). (2) Interrupting bouts of prolonged sitting resulted in a significant increase in cf-PWV (MD = 0.127 m/s, 95% CI = 0.044 to 0.209, p < 0.0026) that was lower compared to the uninterrupted sitting.

An acute bout of uninterrupted sitting appears to increase cf-PWV; although interrupting prolonged sitting with brief physical activity is beneficial, it does not fully mitigate the response.