Thosar, Saurabh S.Bielko, Sylvanna L.Wiggins, Chad S.Klaunig, James E.Mather, Kieren J.Wallace, Janet P.2016-06-152016-06-152015-04-07Thosar, S. S., Bielko, S. L., Wiggins, C. S., Klaunig, J. E., Mather, K. J., & Wallace, J. P. (2015). Antioxidant Vitamin C Prevents Decline in Endothelial Function during Sitting. Medical Science Monitor : International Medical Journal of Experimental and Clinical Research, 21, 1015–1021. http://doi.org/10.12659/MSM.893192https://hdl.handle.net/1805/9968BACKGROUND: This study was designed to test the hypothesis that antioxidant Vitamin C prevents the impairment of endothelial function during prolonged sitting. MATERIAL AND METHODS: Eleven men (24.2 ± 4.4 yrs) participated in 2 randomized 3-h sitting trials. In the sitting without vitamin C (SIT) and the sitting with vitamin C (VIT) trial, participants were seated for 3 h without moving their legs. Additionally, in the VIT trial, participants ingested 2 vitamin C tablets (1 g and 500 mg) at 30 min and 1 h 30 min, respectively. Superficial femoral artery (SFA) flow-mediated dilation (FMD) was measured hourly for 3 h. RESULTS: By a 1-way ANOVA, there was a significant decline in FMD during 3 h of SIT (p<0.001). Simultaneously, there was a significant decline in antegrade (p=0.04) and mean (0.037) shear rates. For the SIT and VIT trials by a 2-way (trial x time) repeated measures ANOVA, there was a significant interaction (p=0.001). Pairwise testing revealed significant between-SFA FMD in the SIT and VIT trial at each hour after baseline, showing that VIT prevented the decline in FMD 1 h (p=0.009), 2 h (p=0.016), and 3 h (p=0.004). There was no difference in the shear rates between SIT and VIT trials (p>0.05). CONCLUSIONS: Three hours of sitting resulted in impaired SFA FMD. Antioxidant Vitamin C prevented the decline in SFA FMD, suggesting that oxidative stress may contribute to the impairment in endothelial function during sitting.en-USPublisher PolicyAntioxidantsOxidative stressSedentary lifestyleArticle