The efficiency of oxygen delivery to tissues is a factor in the severity of major diseases such as Covid-19 and heart conditions.

Scientists already know that the relationship between the length of a person’s index and ring fingers, known as the 2D:4D ratio, is linked to distance running performance, age at heart attack and severity of Covid-19. Is.

Now Professor John Manning, a numerical ratio specialist at Swansea University, is working with colleagues to take a closer look at the subject.

Their results have just been published. American Journal of Human Biology.

The study analyzed 133 professional soccer players as they underwent a series of physical measurements that included measuring the length of digits from a hand scan. They also completed an additional cardiopulmonary test to measure exhaustion on a treadmill.

Professor Manning of the Applied Sports, Technology, Exercise and Medicine (A-STEM) research team said: “Together with our partners at the University of Central Lancashire’s Cypress campus, we have elucidated the relationship between 2D:4D and oxygen metabolism. In a sample of well-trained athletes.

“Athletes with long ring digits (4D) compared to index digits (2D) have an oxygen metabolism such that they reach maximal oxygen consumption in an incremental cardiopulmonary test to exhaustion on a treadmill. “

Longer ring digits are considered a sign of higher levels of testosterone in the uterus than index digits. Testosterone has effects on oxygen metabolism through its influence on the energy producers (mitochondria) within the cells.

He added: “Our findings are consistent with distance running, where longer 4D is associated with higher performance, and cardiovascular disease and Covid-19 where longer 4D is associated with lower disease severity.

“Overall, our study highlights the importance of using healthy well-trained athletes to elucidate metabolic processes that are important in disease outcomes.”

More work is now necessary to quantify these associations in women, the team says.

Professor Manning’s previous research has examined how the difference in the length of the fingers on a person’s left and right hand can provide important information about the outcome of contracting CoVID-19.