The human body uses three main energy systems to carry out physical activity - the ATP-PC system, the lactic acid system and the aerobic system. This programme covers the workings of the three energy systems, the effects of exercise on each of them, effects of exercise on the body, including raising the temperature, fluid and mineral loss, breaking down of muscle tissue and delayed onset of muscle soreness. Various strategies and recovery techniques are examined, including those incorporated into a cool down session after exercise - fluid and carbohydrate replenishment, active recovery and stretching. It also covers passive recovery and its role, and looks at various ways to continue the recovery process in the 24 hours or so after training or playing sport.