A Primer on Repeated Sitting Exposure and the Cardiovascular System: Considerations for Study Design, Analysis, Interpretation, and Translation.

Sedentary behavior, particularly sitting, is ubiquitous in many contemporary societies. This is a major societal concern considering the evidence for a strong association between sitting behavior and cardiovascular disease morbidity and mortality. Unsurprisingly, leading public health agencies have begun to advocate "reduction" in sitting behavior.

Impact of a Novel Training Approach on Hemodynamic and Vascular Profiles in Older Adults.

Exercise training beneficially moderates the effects of vascular aging. This study compared the efficacy of Peripheral Remodeling through Intermittent Muscular Exercise (PRIME), a novel training regimen, versus aerobic training on hemodynamic profiles in participants ≥70 years at risk for losing functional independence. Seventy-five participants (52 females, age: 76 ± 5 years) were assessed for hemodynamic and vascular function at baseline, after 4 weeks of either PRIME or aerobic training (Phase 1) and again after a further 8 weeks of aerobic and resistance training (Phase 2).

Central and peripheral arterial stiffness responses to uninterrupted prolonged sitting combined with a high-fat meal: a randomized controlled crossover trial.

Independently, prolonged uninterrupted sitting and the consumption of a meal high in saturated fats acutely disrupt normal cardiovascular function. Currently, the acute effects of these behaviors performed in combination on arterial stiffness, a marker of cardiovascular health, are unknown. This study sought to determine the effect of consuming a high-fat meal (Δ = 51 g fat) in conjunction with prolonged uninterrupted sitting (180 min) on measures of central and peripheral arterial stiffness.

Arterial stiffness responses to prolonged sitting combined with a high-glycemic-index meal: a double-blind, randomized crossover trial.

Regular exposure to uninterrupted prolonged sitting and the consumption of high-glycemic-index (HGI) meals is independently associated with increased cardiovascular disease risk. Sitting for as little as 1 h can impair the health of both peripheral and central arteries. However, it is currently unknown whether combined acute exposure to uninterrupted prolonged sitting and an HGI meal is more detrimental to global (peripheral and central) vascular health.

Cerebrovascular function response to prolonged sitting combined with a high-glycemic index meal: A double-blind, randomized cross-over trial.

Acute prolonged sitting leads to cerebrovascular disruptions. However, it is unclear how prolonged sitting interacts with other common behaviors, including high- (HGI) and low-glycemic index (LGI) meals. Using a double-blind randomized cross-over design, this study evaluated the effects of prolonged (3 hr) sitting, with a high- (HGI; GI: 100) or low-glycemic index (LGI; GI: 19) meal on total brain blood flow (Q ) and executive function.

Occupational sitting and work engagement among university employees.

This study sought to determine the relationship between occupational sitting and work engagement among university employees. Participants included 103 university employees (age: 48.5 ± 10.

The aortic-femoral arterial stiffness gradient: an atherosclerosis risk in communities (ARIC) study.

Background: The aortic to femoral arterial stiffness gradient (af-SG) may be a novel measure of arterial health and cardiovascular disease (CVD) risk, but its association with CVD risk factors and CVD status, and whether or not they differ from the referent measure, carotid-femoral pulse-wave velocity (cfPWV), is not known.

Method: Accordingly, we compared the associations of the af-SG and cfPWV with (i) age and traditional CVD risk factors and (ii) CVD status. We evaluated 4183 older-aged (75.

Acute Changes in Carotid-Femoral Pulse-Wave Velocity Are Tracked by Heart-Femoral Pulse-Wave Velocity.

Carotid-femoral pulse-wave velocity (cfPWV) is the reference standard measure of central arterial stiffness. However, it requires assessment of the carotid artery, which is technically challenging, and subject-level factors, including carotid artery plaque, may confound measurements. A promising alternative that overcomes these limitations is heart-femoral PWV (hfPWV), but it is not known to what extent changes in cfPWV and hfPWV are associated.

The Effects of Acute Exposure to Prolonged Sitting, With and Without Interruption, on Vascular Function Among Adults: A Meta-analysis.

Background: Exposure to acute prolonged sitting can result in vascular dysfunction, particularly within the legs. This vascular dysfunction, assessed using flow-mediated dilation (FMD), is likely the consequence of decreased blood flow-induced shear stress. With mixed success, several sitting interruption strategies have been trialled to preserve vascular function.

Sitting decreases endothelial microparticles but not circulating angiogenic cells irrespective of lower leg exercises: a randomized cross-over trial.

New Findings: What is the central question of this study? What are the cellular and molecular determinants of increased risk for cardiovascular disease from prolonged sitting? What is the main finding and its importance? Prolonged sitting, independent of calf raise interruption strategies, decreases microparticle counts linked to endothelial activation and apoptosis. An acute bout of prolonged sitting appears to promote paradoxical decreases in microparticle counts, but the implications are not yet clear.

Abstract: Repeated exposure to prolonged sitting increases the risk for cardiovascular disease.

Endothelium function dependence of acute changes in pulse wave velocity and flow-mediated slowing.

Flow-mediated slowing (FMS), defined as the minimum pulse wave velocity (PWV) during reactive hyperemia, is potentially a simple, user-objective test for examining endothelial function. The purpose of the current study was to determine the effects of a known endothelial dysfunction protocol on arm PWV and PWV. Complete data were successfully collected in 22 out of 23 healthy adults (23.

Associations between carotid-femoral and heart-femoral pulse wave velocity in older adults: the Atherosclerosis Risk In Communities study.

Background: Carotid-femoral pulse wave velocity (cfPWV) is widely used in epidemiological studies to assess central arterial stiffness. However, despite being superior to traditional risk factors in predicting cardiovascular outcomes, cfPWV is not routinely used in clinical practice. cfPWV assessments require applanation of the carotid artery, which can be cumbersome, and individual-level factors, including carotid artery plaque, may confound the measurements.

Electrically induced cycling and nutritional counseling for counteracting obesity after spinal cord injury: A pilot study.

The purpose of this pilot study was to determine the preliminary efficacy of interval functional electrical stimulation (FES) cycling combined with nutritional counseling in obese adults with SCI. Community-based individuals with chronic SCI. Ten participants with chronic SCI.

Validity of single-point assessments for determining leg pulse wave velocity in sitting and supine positions.

There has been a great deal of interest into the effects of prolonged sitting on lower limb vascular function. However, most studies use flow-mediated dilation which is technically challenging. A simpler technique is pulse wave velocity (PWV) which can be estimated at any single arterial site of interest using a number of different calculations (Bramwell-hill [PWV ], β-stiffness index [PWV ] and blood flow [PWV ]).

Safety and preliminary efficacy of functional electrical stimulation cycling in an individual with cervical cord injury, autonomic dysreflexia, and a pacemaker: Case report.

Functional electric stimulation (FES) cycling is a commonly used therapeutic exercise modality after spinal cord injury (SCI); however, additional precautions must be taken in certain situations. The purpose of this study was to develop and apply a safety monitoring protocol for autonomic dysreflexia (AD) during FES cycling and to determine if an interval-FES cycling program can be safe and beneficial to an individual with cervical SCI, a history of AD, and a non-dependent cardiac pacemaker.The participant was a 36-year-old male with C6 AIS-C SCI sustained 9 years earlier, intermittent AD, and implanted cardiac pacemaker.

Physical Activity and Pain in Youth With Sickle Cell Disease.

Study objectives were to examine the relationships between physical activity, pain, and psychological distress in youth 8 to 17 years of age with sickle cell disease. Participants were 206 youth with sickle cell disease (M = 11.73 years, 54.

Effects of acute prolonged sitting on cerebral perfusion and executive function in young adults: A randomized cross-over trial.

Exposure to acute prolonged sitting reportedly leads to decreased cerebral blood flow. However, it is unclear whether this exposure translates to decreased cerebral perfusion and executive function or whether simple strategies to break up sitting can maintain cerebral perfusion and executive function. This study sought to answer two questions: in young, healthy adults, (a) does prolonged (3 hr) sitting lead to decreased cerebral perfusion and executive function? and (b) does breaking up prolonged sitting, using intermittent calf raise exercises, prevent changes in cerebral perfusion and executive function? Twenty young, healthy participants (21.

Central cardiovascular hemodynamic response to unilateral handgrip exercise with blood flow restriction.

Aim: Exercise training with blood flow restriction (BFR) increases muscle size and strength. However, there is limited investigation into the effects of BFR on cardiovascular health, particularly central hemodynamic load.

Purpose: To determine the effects of BFR exercise on central hemodynamic load (heart rate-HR, central pressures, arterial wave reflection, and aortic stiffness).

Local exercise does not prevent the aortic stiffening response to acute prolonged sitting: a randomized crossover trial.

Prolonged sitting has been shown to promote endothelial dysfunction in the lower legs. Furthermore, it has been reported that simple sitting-interruption strategies, including calf raises, prevent leg endothelial dysfunction. However, it is unclear whether prolonged sitting affects central cardiovascular health, or whether simple sitting-interruption strategies prevent impaired central cardiovascular health.

The impact of upper-limb position on estimated central blood pressure waveforms.

Pulse wave analysis (PWA) utilizes arm blood pressure (BP) waveforms to estimate aortic waveforms. The accuracy of central BP waveform estimation may be influenced by assessment site local haemodynamics. This study investigated whether local haemodynamic changes, induced via arm tilting ±30° relative to heart level, affect estimated central systolic BP (cSBP) and arterial wave reflection (central augmentation index, cAIx; aortic backward pressure wave, Pb).