The focus of tonight’s presentation is stress and exertion. When faced with a threat like the approach of a predator, a human’s natural response is to turn and flee. Yet a soldier facing enemy guns can choose to stand and fight. Such a decision and the subsequent physical work required involves burning a huge amount of energy. So how does the body deliver such a large amount of energy so rapidly? What happens to the heart, lungs and blood vessels used to transport the energy, and how is it used once it is delivered? In addressing some of these questions, Dr Montgomery takes a close look at the workings of the amazing, high-performance, all-terrain vehicle that is the human body. Viewers will learn what the skeleton is made of, how muscles move the skeleton, what these muscles are made of, how they create force, and how they are controlled by the computer in our skulls. With the help of some intrepid and athletic volunteers, Dr Montgomery explores if all muscles are the same and why it is that some people can sprint well, while others are adept at running for long distances. He then introduces somebody whose ability to keep going despite physical exhaustion saved his life.