Weightlifting monkeys

They did what?

How does working out affect neural strength?

WHAT DID THEY DO?

Researchers at UCL and Newcastle University trained monkeys to pull a weighted handle using one arm, and gradually increased the weight over 12 weeks. Each day, they stimulated the monkeys’ motor cortices (the motor cortex is the part of the brain that is involved in movement) and measured the electrical activity in their arm muscles.

WHY DID THEY DO THAT?

The brain controls movements using two major neural highways connected to the spinal cord: the corticospinal tract (CST) and reticulospinal tract (RST). When people start working out, they initially get stronger by increasing connections in the nervous system, not by growing bigger muscles, but the details of which connections change were unknown.

WHAT DID THEY FIND?

The more the monkeys trained, the more the electrical response from stimulating the cortex and RST increased, while the CST remained unchanged. “These results are not just relevant to bodybuilders pushing for a new PB [personal best]. If we understand the neural mechanisms of strength then we can start to think about how to help individuals suffering from a loss of strength, such as following a stroke,” said co-author Dr Isabel Glover.