Cross training is the simple method to activate the two hemispheres of brain. The right part of the brain is specialized in Visual and Emotional functions while the left brain is Analytical and Verbal. Based on our job and daily brain activities, either left or right part of the brain remains active while the other side is sleepy most of the time. The cross training will improve the neuronal activities and communication between both the brain halves. If you are a person concentrating in Art work or doing lab work, the right part of the brain is more active. If you are doing mathematics or accounting, your left brain is more active. So if you are a mathematician, doing some art work occasionally will cross train the brain.