Finding Main Ideas and Details

“Read the following passage and identify the main idea: \"Your brain gets stronger when you exercise it, just like muscles get stronger when you exercise them. Training your brain isn't always easy or comfortable. Learning math strengthens the parts of the brain that are linked to memory, thought, and action. Learning and practicing things helps strengthen and change our brains. All learning can build new information pathways, but learning things that are challenging for you can supercharge your brain growth.\"”