Effects of Breaking Up Prolonged Sitting on Cardiovascular Parameters: A systematic Review.

The aim of this systematic review was to analyze the acute and chronic effects of sitting breaks on cardiovascular parameters. PubMed and Web of Science databases were searched by two independent researchers for relevant studies published until February 2020. Acute or chronic studies reporting the effects of sitting breaks or reduction in sitting time on cardiovascular parameters were examined. The eligibility criteria followed PICOS: Population - Humans ≥ 18 years old; Interventions - Sitting break strategies; Comparisons - Uninterrupted sitting; Outcomes - Cardiovascular parameters (blood pressure, heart rate, ambulatory blood pressure, vascular function, pulse-wave velocity, cerebral blood flow and biomarkers); Study design - Randomized controlled trials, non-randomized non-controlled trials and randomized crossover trials. Forty-five studies were included, where 35 investigated the acute and 10 the chronic effects of sitting breaks or reductions in sitting time. Walking was the main acute study strategy, used in different volumes (1 min 30 s to 30 min), intensities (light to vigorous) and frequencies (every 20 min to every 2 h). Acute studies found improvements on cardiovascular parameters, especially blood pressure, flow-mediated dilation, and biomarkers, whereas chronic studies found improvements mostly on blood pressure. Breaking up or reducing sitting time improves cardiovascular parameters, especially with walking.

Functional and Cardiovascular Parameters in Peripheral Artery Disease Patients with Interarm Blood Pressure Difference.

BACKGROUND: To analyze the impact of interarm blood pressure difference (IAD) on functional and cardiovascular parameters in patients with peripheral artery disease (PAD). METHODS: Ninety-eight patients with PAD were recruited in this cross-sectional study. Patients with differences between the right and left arms of systolic and/or diastolic blood pressure ≥10 mm Hg were classified as IAD, whereas the remaining patients were classified as PAD control subjects. Functional parameters included were the 6-min walk test, short physical performance battery, walking impairment questionnaire (WIQ), and the walking estimated-limitation calculated by history. Systemic cardiovascular parameters included were arterial stiffness and heart rate variability. Local cardiovascular parameters assessed in both arms were brachial blood pressure and flow-mediated dilation. RESULTS: Patients with IAD presented higher systolic blood pressure and pulse pressure compared with control patients (P < 0.01). The carotid femoral pulse wave velocity tended to be higher and flow-mediated dilation tended to be lower in PAD patients with IAD compared with control subjects (P < 0.09). Patients with IAD presented lower scores in short physical performance battery (P = 0.012), WIQ distance (P = 0.003), WIQ speed (P = 0.008), WIQ stair climbing (P = 0.034), and walking estimated-limitation calculated by history (P = 0.026) when compared with PAD control patients. CONCLUSIONS: In patients with PAD, IAD is associated with lower physical function and impairments in cardiovascular parameters compared with PAD patients without IAD.