(From the Sydney Morning Herald). While, at root, general health is a straightforward matter - excess fat damages your health and longevity, you should eat less, exercise more, and take your supplements - it's not as simple as calories in minus calories out. More complex processes are at work under the hood: "Everyone knows exercise, such as walking, is vital ... the benefits extend far beyond the energy you burn [while exercising] ... it is easy to tell the difference in the laboratory between an active person and a sedentary one by looking at the genes in their muscles. Exercisers have more genes switched on that control enzymes that allow muscles to burn more fat. ... Dropping below an activity threshold appears to switch off some genes, reducing the number of mitochondria, the energy-producing parts of the cells that readily convert fat to energy. 'And if you can't burn fat there's only one outcome: you store it.' It takes at least three or more months of sustained activity to change this metabolism for the better."