New research has found that as humans evolved their brain began consuming a greater amount of energy, taking away from that which could be spent on physical strength.

According to LiveScience.com, the researchers essentially found that man traded brawn for brains over time. The human brain is the most powerful computer known on Earth, with 100 billion neurons and one quadrillion (one million billion) synapses making all these tiny neurological connections.

"Even after so many years of research of humans and human evolution, we still can uncover large unknown differences between humans and other species," study co-author Philipp Khaitovich, an evolutionary biologist at the Chinese Academy of Sciences' Key Laboratory of Computational Biology in Shanghai, told LiveScience.com.

The human brain is far more complex than any of its closest animal relatives, such as chimpanzees or apes. The researchers found that a metabolism change likely contributed to the brain consuming more energy, approximately 20 percent in all.

For their study, published in the journal PLOS Biology, the researchers examined metabolites in the brain's primary visual, prefrontal and cerebellar cortexes. Examining the three regions of the brain, as well as metabolite levels in the thigh muscle and kidney, they were able to tell how the body distributed energy via the tiny molecules tied directly to metabolism.

By comparing their results in humans to those in rhesus monkeys and chimpanzees, the researchers were able to see the major evolutionary differences.

"The world of human metabolomics is just starting to open up its secrets to us," study co-author Dr. Patrick Giavalisco, of the Max Planck Institute for Molecular Plant Physiology in Golm, said in a press release. "Such human-specific metabolic features we find could be related not only to physical or cognitive performance but also to common human metabolic diseases."

They concluded that the human metabolism changed to give more energy to the brain when it became more important to everyday life.

"For a long time we were confused by metabolic changes in human muscle," study lead author Dr. Kasia Bozek, said in the release, "until we realized that what other primates have in common, in contrast to humans, is their enormous muscle strength.

"Our results suggest a special energy management in humans, that allows us to spare energy for our extraordinary cognitive powers at a cost of weak muscle."