There are a number of different techniques of resistance training for strength improvement, including isometric exercise, progressive resistive exercise, isokinetic training, circuit training, and plyometric exercise. Regardless of which of these techniques is used, one basic principle of training is extremely important. For a muscle to improve in strength, it must be forced to work at a higher level than that to which it is accustomed. In other words, the muscle must be overloaded. Without overload the muscle will be able to maintain strength as long as training is continued against a resistance the muscle is accustomed to.
To most effectively build muscular strength, weight training requires a consistent, increasing effort against progressively increasing resistance. Progressive resistive exercise is based primarily on the principles of overload and progression. If this principle of overload is applied, all three training techniques will produce improvement of muscular strength over a period of time.
