Sitting-Induced #AorticStiffening CANNOT be Countered With 10 Reps of #CalfRaises Every 10 Minutes! Study in Healthy, Young Subjects Shows You've Been *Pumping* in Vain 😏… Scientists from the University of Maryland sought to answer two questions: in young, healthy adults (i) does prolonged sitting (3h) lead to increased aortic stiffness? and (ii) do intermittent calf raise exercises to prevent pooling, also prevent aortic stiffening?
To this end, twenty young, healthy participants (21.7±2.5 y, 70% F, 25.5±6.1 kg/m2) were randomized to 3 h of sitting with (CALF) or without (CON) 10 calf raises every 10 min. Aortic stiffening (carotid-femoral pulse wave velocity, PWV) was measured in the supine position pre- and post-sitting. Venous pooling during sitting was estimated with total hemoglobin (tHB) concentration using near-infrared spectroscopy.
The analysis of the results shows that "[t]here were no condition x time interactions." More specifically, following 3 h of sitting, PWV significantly increased (0.30±0.46 m/s, p <0.001). There was no condition effect for PWV (p=0.694), indicating the intermittent calf rises did not preserve central cardiovascular health. tHb was not significantly affected by sitting (p=0.446) but was 1.9 μM higher for CON vs. CALF (p=0.106). This has the authors conclude: "Sitting increases aortic stiffness in young, healthy individuals, a process that may be influenced by lower extremity blood pooling. Calf raises, which have been reported to preserve vascular function in the legs, do not appear to provide sufficient stimulus for maintaining central cardiovascular health." suppversity.com | https://www.physiology.org/doi/abs/10.1152/japplphysiol.00318.2019