<span>A child who is unable to focus in the classroom due to hunger, it could be argued that the child's nutritional needs have not been met. As the body is focused on satisfying it's need for sustenance, it will be less focused on the lesson in the classroom. Basic survival is a far stronger driver of attention than higher level knowledge.</span>
That statement is true. If your body is not at the right temperature before doing an exercise that includes flexibility (almost every one), you are more likely to pull or tear a muscle.