The principle of overload is easily described using an example of resistance training. To increase muscular strength, you must progressively increase the amount of weight you lift. By increasing the amount of weight you lift, you overload your muscles. Your muscles respond to this overload by getting larger (hypertrophy). Many exercise scientists study the effect of resistance training on muscles to see how athletes can overload their muscles and increase their strength. Strength and conditioning specialists are professionals who use exercise science and apply the principles of overload, progression, specificity, rest, and recovery to help athletes improve all components of health-related physical fitness. Understanding the overload principle and the progression principle (see chapter 4) will enable you to structure an exercise program for the purpose of increasing components of your health-related physical fitness.
