You are tired? Pregnancy is like a 40 week marathon!

Researchers studying the limits of human endurance have determined that the physical intensity of pregnancy is similar to that of a 40-week marathon!

So if you feel tired.. there’s a reason!

Every woman who has gone through a pregnancy feels like you ran a 40-week marathon on your own. Without making any stops and any type of relay.

In short, pregnancy is a path that human beings, or rather, women , are able to do with the maximum duration and with the maximum expenditure of energy.

Are you surprised? Probably not because you are living it or have lived it on your skin, and you know what we are talking about.

The fatigue of pregnancy

The researchers, in a  study published in June 2019 in Science Advances , went to analyze athletes of some of the most demanding races in the world. Cyclists of the Giro di’Italia, the Spanish Vuelta and the Tour de France; athletes of the Race Across the USA (RAUSA) who complete a marathon a day (42.2 km), for 6 days a week, from 14 to 20 days from the Pacific coast to the Atlantic coast, the Ironmans of triathlon and arctic trekking.

Scholars have gone to evaluate the metabolism and the amount of calories needed to operate the body when it is at rest, and when they are under exertion.

The  basal metabolic rate (BMR) , or BMR , they explain on Wikipedia , “ is the energy expenditure of a living organism at rest, therefore including the energy necessary for vital metabolic functions (respiration, blood circulation, digestion, nervous system activity, etc.). It accounts for about 45-75% of total energy expenditure for the day.”

According to the study, adults are able to burn calories up to 2.5 times their basal metabolic rate, or about 4,000 calories a day.

Prolonged physical activities above this metabolic ceiling (~2.5 × MB) require the consumption of energy reserves and are not infinitely sustainable . Humans worldwide show very similar metabolic ranges, always less than or equal to 2 × MB, during daily life, regardless of activity and lifestyle differences.

Pregnant women , according to the researchers, “work out” at 2.2 times their basal metabolic rate, nearly the maximum possible, every day , for about 270 days in a row . If the rate were much higher than this, pregnancy would be unsustainable, harmful to the body and potentially fatal.

Marathon runners’ energy use peaks at about 15.6 times their basal metabolic rate, but only maintains the extremely high rate for a short period of time. By contrast, Tour de France cyclists move at 4.9 times their resting altitude during the 23-day race, and Antarctica trekkers who lift the 500-pound barges through snow-covered ground for 95 days arrive at 3.5 times their basal metabolic rate.

The problem of limiting is not our heart rate or lung capacity , but our digestive systems. Humans, experts say, simply can’t properly process enough calories to sustain sustained energy consumption above the 2.5 limit. More than that and our body would start wearing out its own tissue.

So dear pregnant women don’t feel guilty about an extra ice cream or skipping a prenatal yoga or swimming class. Watch out for weight gain , sure, so adjust your diet, but don’t forget to reward yourself, because having this baby will be the biggest chore of your life.