According to Gizmodo "Researchers in Canada say they’ve come up with two simple physical techniques to help prevent a common cause of dizziness and fainting. In a small trial, they found that these maneuvers, which involve nothing more than moving your lower limbs, could effectively reduce the symptoms of initial orthostatic hypotension, a condition that temporarily leaves people light headed when they stand up. ... Orthostatic hypotension is a form of low blood pressure that happens when people stand up from sitting or lying down, leading to dizziness or even fainting. Often, this condition can be linked to underlying neurological problems, or it can happen as a side effect of many medications, and these cases tend to affect older people. But other times, this drop in blood pressure comes and goes very rapidly, within as little as a minute, and it may not be linked to any other health problems; this form is called initial orthostatic hypotension (IOH) and it tends to affect younger people."
The study, published in Heart Rhythm, states "Initial orthostatic hypotension (IOH) is a form of orthostatic intolerance defined by a transient decrease in systolic blood pressure (SBP) >40 mm Hg or diastolic blood pressure (DBP) >20 mm Hg within the first 15–30 seconds of assuming an upright position.
This drop in blood pressure (BP) typically is associated with symptoms of presyncope (including lightheadedness, nausea, and blurred vision) and occasionally syncope as a result of cerebral hypoperfusion, and usually recovers within 45–60 seconds due to triggering of the arterial baroreflex.
Heart Rhythm went on to report that "2 interventions, in random order, followed by the other intervention [were conducted]. One was lower body muscle preactivation through repeated knee raises [for 30 seconds] prior to standing (PREACT), and the other was lower body muscle tensing through leg crossing and tensing [for 30 seconds] after standing (TENSE). ... This study demonstrated that lower body muscle preactivation attenuates the BP drop, and symptoms, of IOH upon standing. This study also confirmed that leg crossing with muscle tensing after standing attenuates the MAP drop, and symptoms, of IOH upon standing. These are simple, effective, and cost-free interventions that patients can use to prevent their symptoms from IOH."
As published in Science Alert, "so simply standing up as normal – both exercises made a significant difference in limiting the temporary drop in blood pressure and relieving the symptoms of IOH.
"Since it is a physical maneuver, it simply requires the lower body limbs, which patients can utilize at anytime and from anywhere to combat their symptoms," says clinical researcher Nasia Sheikh from the University of Calgary in Canada.
It's thought that IOH is caused by an opening of the blood vessels, triggered by the process of standing up. What these exercises might be doing, then, is counteracting that response, and the researchers say the two exercises could also be used in tandem.
Right now, those who experience IOH – thought to be up to 40 percent of the general population in the US – don't have any specific treatments available. Up until now, the best advice has been to try to stand up as slowly and as gradually as possible.
Although the sample size in this study was a small one and only involved women, these exercises could potentially change that situation. A little light-headedness might not seem like a huge problem, but it impacts daily life and can, in some cases, lead to fainting and a loss of consciousness.
"Almost everyone has probably experienced some light-headedness at some time after standing up," says Satish Raj, a cardiologist at the University of Calgary. "For some people, this is a frequent occurrence and may happen several times a day, which can be very frightening and negatively impact their quality of life.""