If you’ve ever felt faint upon sitting, you may have wondered if this is because your blood pressure drops when you lower your body.
“A sudden drop in blood pressure should not result from sitting,” says William Manger, MD, PhD, founder of the National Hypertension Association, professor emeritus at the New York School of Medicine, and author of the book, “Live Longer, Live Better: Avoid the Risks.”
Dr. Manger explains, “However, a sudden drop in blood pressure may occur with suddenly standing from a seated or recumbent position.
“This may especially occur in older persons, since their vascular response to standing (i.e., their blood vessels’ constriction to standing) may be less rapid than that occurring in younger persons.”
When you stand, the vascular system is supposed to, via valves in the veins, prevent blood from draining out of the brain due to gravity.
This vagal response in some people is delayed or slow to react, hence causing that syncope sensation or a feeling like one is going to pass out.
During these episodes, called orthostatic hypotension, the blood pressure suddenly drops in response to a quick rise from a seated, recumbent-seated (reclined back) or lowered position.
Lowered positions that can result in orthostatic hypotension include sustained squatting or kneeling; the positioning for the bent-over dumbbell row exercise; and yoga positions.
Solutions for Preventing Syncope or a Faint Feeling
• Rise slowly from your chair or bed.
• Rise slowly from your squat or kneel.
• Clench your fists upon rising. Some yoga instructors advise their students to do this when rising off the floor to a standing position.
• Don’t obsess about the condition. This tends to bring it on more. Some people find that when their orthostatic hypotension is absent, it’s when their mind is distracted by busyness as they bolt up from a seated position.
• Stay hydrated.
If you forget to take the above measures and feel the room turning black, of course you already know that sitting back down again corrects the problem – or at least leaning into something stable and bending forward.
We’d really be in big trouble if sitting caused a sudden drop in blood pressure, what with all the sitting that modern peoples do every day.
Dr. Manger, who began practicing medicine in 1949, has conducted research on the mechanism of salt-induced hypertension, and has published research in peer-reviewed journals.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.