At 23-years-old, Michel Siffre embarked on an interesting experiment

A man who lived in a cave for a long period of time had absolutely no concept of time, leading to massive impacts on his body clock.

The outside world is a busy place, there’s no doubt about that. So Michel Siffre decided to cut himself off from the world in 1962 for a staggering two months.

How he did that you ask? Well, he lived in a cave, which led to some incredible effects on his body and mind.

Michel was inspired by the space race and ultimately decided to position himself 130 metres below the surface in the Scarasson, a mountain in the Ligurian Alps.

The French explorer decided not to take his wrist watch down with him and cell phones were few and far between back then.

Michel lived in a cave for two months (PHILIPPE DESMAZES/AFP via Getty Images)

As a result, Michel lost all concept of time, surely making it a nightmare when deciding what meal is next.

At the young age of 23, Michel decided to place himself next to a glacier. He would sleep and drink when his body told him, rather than the times society says you should sit down for that evening meal.

Michel’s incredible findings lifted the lid on how humans would react to no clocks, calendars or sunshine to inform them what time of day it is.

Speaking about the outlandish mission, Michel told Cabinet Magazine in 2008: “This idea came to me—this idea that became the idea of my life. I decided to live like an animal, without a watch, in the dark, without knowing the time.

“Instead of studying caves, you ended up studying time. Yes, I invented a simple scientific protocol.

“I put a team at the entrance of the cave. I decided I would call them when I woke up, when I ate, and just before I went to sleep. My team didn’t have the right to call me, so that I wouldn’t have any idea what time it was on the outside.

The explorer had no concept of time (Patrick Durand/Sygma via Getty Images)

“Without knowing it, I had created the field of human chronobiology.”

During his time in the cave, Michel took his pulse and conducted his own ‘psychological test’.

“I had to count from 1 to 120, at the rate of one digit per second. With that test we made a great discovery: it took me five minutes to count to 120. In other words, I psychologically experienced five real minutes as though they were two,” Michel explained.

Surprisingly, the time went extremely quick for the Frenchman as he believed a month was still to run on the expedition when told by those on ground it was time to get out.

Michel was sensitive to light when he came out of the cave (Keystone/Getty Images)

“My psychological time had compressed by a factor of two,” he added.

The explorer continued: “I believe that when you are surrounded by night—the cave was completely dark, with just a light bulb—your memory does not capture the time.

“You forget. After one or two days, you don’t remember what you have done a day or two before. The only things that change are when you wake up and when you go to bed.

“Besides that, it’s entirely black. It’s like one long day.”