Is It Bad to Cross Your Legs When You Sit?

Crossing your legs is an extremely common habit; most people don’t even notice that they’re doing it when they sit down. While you may find it comfortable to sit with one knee crossed over the other. it might be causing health problems that you are not aware of.

A study published in Blood Pressure Monitoring stated that sitting with your legs crossed can increase your blood pressure. This happens because the blood in your legs has to work against gravity to be pumped back to your heart, crossing one leg over the other Increases resistance (阻力), making it even harder for the blood to circulate. This causes your body to increase your blood pressure to push the blood back to the heart. You won’t feel any immediate effects, but if you sit for long periods of time it’s important that you take note of how long you have your legs crossed for. You shouldn’t have your legs crossed for more than 15 minutes. and it’s important that you get up and walk around at least once every hour.

Crossing your legs can also lead to neck and back pain. Ideally, it’s best for our bodies to sit with our feet planted flat, hip width apart, on the floor, but it’s not easy to maintain perfect posture all day at the office. When you sit with your legs crossed your hips are in a twisted position, which can cause one of your pelvic bones (骨盆) to rotate. Since your pelvic bone supports your neck and spine, this can cause pressure on your lower and middle back and neck.

You also might notice that when you sit with your legs crossed for long periods of time your feet and legs get tingly or have the feeling of being asleep. This is because when one leg sits on top of the other it causes pressure on the veins and nerves in your legs and feet. It can cause pumbness and/or temporary paralysis in the legs, ankles, or feet While the feeling of discomfort may only last a minute or two, repeatedly crossing your legs until they feel numb can cause permanent nerve damage.

So next time you sit down, try to get yourself in the habit of sitting with both of your feet on the floor. Not only will it help your posture and stability, but it will also save your health in the long run.

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All of us face a variety of risks to our health in our daily life. Driving cars and being exposed to environmental pollutants all pose certain degrees of risk. Some risks would restrict our ability to lead a good life. And some are risks we might decide to avoid if we had the opportunity to make informed choices. Indoor air pollution is one risk that you can do something about.

Scientific evidence has indicated that the air within homes can be more seriously polluted than the outdoor air in even the most industrialized cities. Other research indicates that people spend approximately 90 percent of their time indoors. Thus, for many people, the risks to health may be greater due to exposure to air pollution indoors than outdoors.

In addition, people exposed to indoor air pollutants for the longest periods of time are often those most susceptible to the effects of indoor air pollution. Such groups include kids, the elderly and the chronically ill, especially those suffering from respiratory disease.

While pollutant levels from individual sources may not pose a significant health risk by themselves, most homes have more than one source that contributes to indoor air pollution. There can be a serious risk from the cumulative effects of these sources. Fortunately, there are steps that most people can take both to reduce the risk from existing sources and to prevent new problems from occurring. This brochure was prepared by the U. S. Environmental Protection Agency (EPA) and the U. S. Consumer Product Safety Commission (CPSC) to help you decide whether to take action that can reduce the level of indoor air pollution in your own home.

Because so many Americans spend a lot of time in offices with mechanical heating and cooling systems, there is also a short section on the causes of poor air quality in offices and what you can do if you suspect that your office may have a problem.

Dreams, according to Carl Jung, reveal a certain amount of reality hidden during waking consciousness. In Jungian philosophy, the conflict and chaos experienced in dreams finally bring order to our lives. While Jung’s mystical theories are debatable, he was not mistaken about the importance of dreaming. A growing number of reports show that a continuous lack of dreaming is damaging our waking hours in many ways.

This trend is causing damage to our immune and metabolic (新陈代谢的) systems, let alone the electronic products that keep us up late at night are ruining our sleep patterns, which has long-term consequences on our memory system. One study showed that not allowing mice to have adequate amounts of REM (Rapid Eye Movement) sleep, the stage in which we dream, the mice couldn’t strengthen memories.

You might think this is just a sleep problem, but dreaming is inseparable from our night-time rest. We sleep in cycles, each lasting about 90 minutes; in a sleep cycle, we go through non-REM sleep before hitting REM. As the night progresses, REM sleep periods increase in length while deep sleep (one of the stages of non-REM sleep) decreases. The longer we sleep, the more time we spend in REM, which is why we are often dreaming when waking up in the morning. If we sleep less than seven hours, however, it becomes harder to achieve this level of REM.

The combination of sleeping and dreaming acts as an emotional stabiliser. We recover from emotional hurt faster when we sleep and dream properly. However, we’re not getting enough sleep to cycle through the stages to take advantage of this natural circadian anti-depressant (抗抑郁剂) — dreams. Instead, we get depressed and turn to alcohol or medicines to get to sleep, which only makes things worse because even one drink leads to late REM while anti-depressants promote deep sleep at the expense of REM.

We’re paying for this lack of dreaming in many ways. For example, a 2021 study stated that compared with quiet rest and non-REM sleep, REM promoted the formation of associative networks and the integration (整合) of unassociated information. Volunteers that experienced more REM sleep were better equipped for solving problems requiring creative solutions.

Rowan Hooper, the managing editor at New Scientist, writes that dreams that include an “emotional core” appear to be a main function of REM sleep and that we should look at sleep patterns as seriously as we do diet and exercise habits.