Is Sitting With Legs Crossed Really Harmful to Your Health?

Girls are often told to “sit like a lady”; which means that instead of sitting with legs spread, they should either put their legs together, or cross one over the other at the knee or ankle. But certain studies have claimed that crossing one’s leg with one knee over the other can be linked to increased blood pressure, varicose veins, and nerve damage. But are these claims really accurate, or deserving of closer examination?

While it is true that if you spend too much time in exactly the same position, eventually your leg or your foot can go numb. This is because crossing the legs can put pressure on the peroneal nerve behind the knee, which supplies sensation to the lower legs and feet. But should this happen, it is only temporary.

Maintaining a particular posture for many, many hours can however lead to a condition called peroneal nerve palsy which may eventually result in “foot drop” – where you can’t lift the front part of your foot and toes. In reality though,  long term numbness is an unlikely consequence of leg-crossing because as soon as we feel uncomfortable, we tend to move and change position.

What about Blood Pressure?

When you get it checked, the doctor or nurse tends to ask you to rest your arm on the chair or table and to uncross your legs, putting your feet flat on the floor. The fear is that crossed legs might skew the reading by temporarily raising your blood pressure.

Studies have indeed found that leg crossing does result in a higher blood pressure reading, while another study found it made no difference. But they also found that blood pressure reading depended on how many times the test is carried out, and the time interval between these tests. The greatest rise in blood pressure though, occurred in people already being treated for high blood pressure.

Two possible mechanisms have been proposed to explain why leg-crossing might lead to a temporary rise in blood pressure. One is that the action of putting one knee over the other sends blood from the legs up to the chest resulting in an increased quantity of blood being pumped out of the heart, raising blood pressure.

An alternative explanation is that blood pressure rises because exercise without the joints moving – which happens with when you cross your legs at the knee – increases the resistance to the blood passing through the vessels. This might explain why crossing legs at the ankles doesn’t have the same effect.

So crossing the legs does appear to cause a temporary rise in blood pressure, but there are no evidence of any long-term consequences, except that people at high risk of blood clots are advised not to cross their legs for long periods of time because this may increase their  risk of a deep vein thrombosis – a medical condition where clots are formed in the deep veins of your body, usually the legs which can cause harm in other parts of the body if these clots break loose

And Varicose Vein?

Usually tiny valves in the blood vessels prevent blood from flowing back in the wrong direction, but if those valves become stretched and weakened, the blood can pool, resulting in the enlarged veins called varicose veins. Crossing the legs has not been demonstrated to be a crucial factor. Whether or not you get varicose veins seems, partly at least, to be down to genetics.

So if you like crossing your legs – lady or not – you are unlikely to do yourself any damage, provided you don’t stay in the same position until your legs are numb. Well, except you have a prevailing condition that predisposes you to harm as mentioned above.

Source: BBC Future