In response to a small 2018 examine printed in Chronobiology Worldwide, sleeping upright might place the physique in a state of higher physiological arousal, subsequently making sleep harder. The researchers defined that sleeping upright suppresses the physique’s “relaxation and digest” exercise, which is regulated by the parasympathetic nervous system. As an alternative, it prompts the physique’s sympathetic nervous system, which is related to stress and heightened consciousness akin to after we’re in “fight-or-flight” mode. This was evidenced by the truth that out of six examine contributors, sleeping for 4 hours in an upright seat decreased complete sleep time by 29%, slow-wave sleep by 30%, and REM sleep by 79% compared to sleeping in a chair that reclined utterly flat.
One other factor that may occur after we sleep sitting up is that our physique might develop into extra inclined to blood clots, studies Sleep Advisor. Prolonged time spent sitting can result in the event of deep vein thrombosis, during which blood clots kind within the legs. If these blood clots make their solution to different components of the physique, akin to our respiratory tract, it may be life-threatening. Discuss to your doctor in the event you expertise signs of ache, swelling, pores and skin discoloration, or pores and skin that feels heat to the contact.