When you get up suddenly, you will faint. These two movements can be relieved easily.

Many people have the experience of standing up suddenly and feeling dizzy after sitting for too long. In fact, such a small symptom is related to the blood flow of our whole body. Now, a study has found two simple ways to learn them to help you relieve these symptoms immediately.

Slumped on the sofa watching TV, I heard the doorbell suddenly get up and open the door. I only felt dizzy. After a long time at my desk, I got up from my seat and stretched myself, but suddenly my eyes went dark. I believe many people have had a similar experience. Usually, however, these symptoms subside after a few seconds, with a sigh of "Oh, it's getting worse" at most.

In fact, symptoms such as temporary dizziness and blurred vision after standing up quickly are usually caused by a significant drop in blood pressure in a short period of time, which is known as "initial orthostatic hypotension" (initial orthostatic hypotension,IOH). It affects about 40% of people, and the incidence is higher in the elderly.

For most people, the feeling of "almost fainting" after a few seconds is not too disturbing, but severe IOH patients do have syncope. Imagine how dangerous it is t× systolic blood pressure + 2 × diastolic blood pressure), and the discomfort symptoms of IOH were also significantly alleviated.

Two principles

Interestingly, there was no significant difference in the improvement of mean arterial pressure and symptoms between "preactivation" and "tension", but there were differences in specific hemodynamic data. it shows that the two methods achieve the goal of reducing the decrease of blood pressure and relieving symptoms in different ways.

Mean arterial pressure is approximately equal to the product of cardiac output (the amount of blood injected into the artery on one side of the ventricle per minute) and total peripheral resistance (resistance to blood flow in systemic circulation). These three basically correspond to the relationship between blood pressure, blood volume and vascular thickness just mentioned. The researchers found that the "pre-activation" method to increase mean arterial pressure mainly depends on the increase of cardiac output, while the "tension" method increases both cardiac output and total peripheral resistance.

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The principle that the "pre-activation" method works is actually different from what the researchers originally imagined. As described above, the researchers hypothesized that "pre-activating" skeletal muscle weakens the vasodilation reflex caused by transient muscle contraction. However, the results showed that the decrease of total peripheral resistance in the pre-activation group was the same as that in the control group. In other words, the "pre-activation" method did not affect the degree of final vasodilation, but moderated the drop in blood pressure during standing up by increasing cardiac output.

In contrast, the increase in cardiac output during standing in the "taut" group was not as high as that in the "pre-activated" group, but at the same time, the decrease in total peripheral resistance in the "taut" group was reduced, perhaps because of compression on the blood vessels in the legs during cross standing. The superposition of the two effects on cardiac output and total peripheral resistance makes the effect of "tension" method and "pre-activation" method similar to that of "preactivation" method in alleviating the decrease of mean arterial pressure.

The researchers also believe that the effect of the combination of "pre-activation" and "tension" can be verified by further experiments. They also said that the participants in the current study were all women and that future studies should also include male participants to verify whether there were

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