For me, the movie The Princess Diaries changed many things. Anne Hathaway's character Mia and I learnt together how 'princesses' were supposed to sit and wave—yes, i did practice it a lot.
But, what I didn't know back then was that I was saving myself from the bad habit of crossing my legs at the knees. Many people do this while sitting and often think of it as a 'ladylike' pose. Well, a scientific study proved that crossing legs can cause increase your blood pressure which doesn't happen when you cross the legs at the ankles.
When you put one knee over the other, all the blood goes up to the chest instead. Heart starts pumping large quantity of blood which increases the blood pressure.
But, that's not all because this position can also lead to pelvic imbalance. A study showed that sitting with legs crossed for over three hours a day could result in stooped posture, lower back and neck pains. Also, prolonged leg-crossing eventually makes the inner thigh muscle shorter and the outer thigh muscle longer, and puts your joints at risk of moving out of place.