A team of researchers from the University of Southern California made an interesting discovery about the Hadza ethnicity of Tanzania, a population of a few hundred people who live hunting and gathering food near Lake Eyasi.
They found that members of this ethnic group seem not to present the main markers for heart and metabolic diseases, markers that are common in people of industrialized nations. The researchers soon came to a conclusion: members of this ethnic group used to squat or kneel very often, more often than they could sit.
The researchers carried out a study on some members of this population by making them wear devices to measure physical activity and rest periods. In addition to having good levels of physical activity, members of this ethnic group also show high levels of inactivity.
Members In fact, for 9-10 hours a day, children of this ethnic group are used to kneel or crouch, for example, around a fire. These are resting postures that still involve a minimum of muscular activity compared to sitting, which practically does not involve any.
And this conclusion leads to another one: squatting and kneeling can be considered as resting positions for human evolution and even favourable for health compared to sitting.
Indeed, various studies have highlighted the negative aspect of sitting for many hours a day, a position which has repeatedly shown that it can increase the risks of various diseases, including cardiovascular diseases. This is because the sitting position involves a very low if not no muscle activity and consequently a low level of metabolism continued for hours hours.
According to researchers at the American University, the rest positions used before the invention of the chairs were basically squatting and kneeling, two positions that involve higher levels of muscle activity than sitting.
Precisely because of this, these positions can help people protect themselves from the harmful effects of inactivity while not doing any exercise per se.
David Raichlen, professor of biological sciences and one of the authors of the study, thinks that human physiology itself has adapted to the conditions we wanted it to. This means that if inactivity and sitting down are harmful things, the evolutionary history of human beings has evidently not given much space to this type of inactivity, unlike what we do today, a time when sitting down has become the primary activity of the day for many people.