Final answer:
To reduce the risk of injury while progressively increasing the training stimulus, it is recommended to follow the 10 percent rule and increase the intensity of the exercise by 10 percent each week.
Step-by-step explanation:
For effective strength training, the intensity of the exercise must continually be increased. To reduce the risk of injury while progressing, it is recommended to follow the "10 percent rule." This rule states that the training stimulus should be increased by 10 percent each week. By gradually increasing the intensity of the exercise, the body can make positive adaptations without overwhelming the muscles or joints.