Sitting-induced Endothelial Dysfunction Is Prevented in Endurance-trained Individuals

Abstract

Purpose Prolonged sitting impairs leg endothelial function, which seems to be mediated by a sustained reduction in blood flow-induced shear stress. However, whether regular endurance training is effective in preventing sitting-induced leg endothelial dysfunction remains largely unknown. Herein, we tested the hypothesis that sitting-induced leg endothelial dysfunction is prevented in high endurance-trained individuals. Methods The endurance-trained group comprised 10 male collegiate cyclists, and the untrained group comprised nine men with no regular endurance training. Peak oxygen uptake (V˙O2peak) was initially determined in all participants using incremental exercise test (37.9 ± 4.7 mL·min−1·kg−1 in the untrained group versus 60.8 ± 3.6 mL·min−1·kg−1 in the endurance-trained group). At second visit, the popliteal artery flow-mediated dilation (%FMD) was assessed before and after a 3-h sitting period. During the sitting period, the popliteal artery diameter and blood velocity were measured every hour. Results The popliteal artery blood flow and shear rate were significantly and similarly reduced during the sitting period in both groups (P < 0.001). In a 3-h sitting, a significant impairment in popliteal artery %FMD was observed in the untrained group (P = 0.003), but it was prevented in the endurance-trained group (P < 0.196). Conclusions In conclusion, the present study revealed that sitting-induced leg endothelial dysfunction is preventable in endurance-trained individuals.

Detrimental effects of physical inactivity on peripheral and brain vasculature in humans: Insights into mechanisms, long-term health consequences and protective strategies

“…In agreement with this, Walsh et al (2017) have shown that when the leg is bent at 90° at the hip and knee during the lateral lying down position, there is a significant decline in popliteal artery FMD, similarly to what has been observed during sitting. This was further accompanied by reductions in mean, anterograde, and retrograde shear rate within the first hour of arterial bending, which partially reflects what has been observed during prolonged sitting ( Thosar et al, 2014 ; Thosar et al, 2015a ; Thosar et al, 2015b ; Morishima et al, 2020a ; Morishima et al, 2020b ). This highlights that turbulent flow patterns induced by arterial bending might also contribute to declines in endothelial function during prolonged sitting.…”

“…To date, only two studies have shown significant decline in brachial FMD in response to uninterrupted sitting (i.e., 2.5, and 4 h) ( Cho et al, 2020 ; Headid et al, 2020 ), with one of those two studies showing concomitantly a marked decline in popliteal FMD ( Headid et al, 2020 ). In agreement with Restaino et al (2015) , many others have shown that shorter sitting trials (1–3 h) have detrimental effects on endothelial function not only in the popliteal artery (2.3–4.1% FMD) ( Morishima et al, 2016 ; Restaino et al, 2016 ; Morishima et al, 2017 ; Vranish et al, 2017 ; Morishima et al, 2020a ; Morishima et al, 2020b ) but also in the upstream superficial femoral artery (2.4–2.7% FMD) in young healthy adults ( Thosar et al, 2014 ; Thosar et al, 2015a ; Thosar et al, 2015b ; Ballard et al, 2017 ). In addition, recent studies have found that the common femoral artery is affected by sitting-induced vascular dysfunction, measured by passive leg movement (PLM)-induced hyperaemia ( Garten et al, 2019a ; Garten et al, 2019b ; Decker et al, 2021 ), an alternative method to assess endothelial function ( Gifford and Richardson 2017 ).…”

“…Prolonged sitting has also been shown to have detrimental effects on blood pressure (BP). However, the literature remains unclear with some studies reporting no sitting-induced variations in BP (e.g., Restaino et al, 2016 ; Carter et al, 2019 ; Headid et al, 2020 ), whilst several studies have detected significant increases in either systolic (SBP), diastolic (DBP), or mean arterial pressure (MAP) in response to short bouts of sitting (i.e., 3–7 h) (e.g., O’Brien et al, 2019 ; Morishima et al, 2020a ; Morishima et al, 2020b ). For example, Younger et al (2016) have reported that 5 h of sitting leads to increases in MAP of approximately 5 mmHg, in healthy young adults.…”

The Acute Effects of Prolonged Uninterrupted Sitting on Vascular Function: A Systematic Review and Meta-analysis

“…The population and design of each study are reported in Supplementary Table 1 (see Table, Supplemental Digital Content, Appendix, http://links.lww.com/MSS/C407). From the 31 studies included in the analyses, vascular function was assessed in a total of 484 participants: healthy, 322 (9,10,17,18,20–26,36–49); overweight or obesity, 121 (7,50–52); metabolic syndrome, 5 (53); and T2D, 36 (42,54). No participants from any of the included studies were described as having impaired fasting glucose or impaired glucose tolerance.…”

Influence of Sedentary Behaviour Interventions on Vascular Functions and Cognitive Functions in Hypertensive Adults—A Scoping Review on Potential Mechanisms and Recommendations

“…Owing to a great increase in computer-based jobs in modern workplaces, a substantial increase in sedentary behaviour has become evident across modern workspaces [ 1 ] Contemporary evidence claims a strong association between the occupational sedentary behaviour and the early cardiometabolic disease risk [ 2 ]. Empirical evidence claims unfavorable vascular effects associated with prolonged sedentary times [ 3 ].…”