When we hear the word "fitness" our minds often brings us to think about physical fitness. We might envision someone who is in great shape or a person that can complete demanding physical activities without a problem. Physical fitness is not the only fitness we should think about regularly.
What I have come to find over the years is that mental fitness is just as important if not MORE important than physical fitness. Our mental fitness is the thing that gives us the courage to try things that we may be afraid or hesitant to try. It helps us to think through tough decisions, and stay sane through tough circumstances. It is also what helps us to stay sharp and quick thinking.