Final answer:
One should change one or more of their FITT settings when their body adjusts to the current exercise program.
Step-by-step explanation:
The FITT principle is a framework used to design and modify exercise programs. FITT stands for Frequency, Intensity, Time, and Type of exercise. One or more of these settings should be changed when your body adjusts to your current exercise program. This is because as your body adapts to the demands of a particular exercise, it becomes more efficient, and the benefits decrease over time.
Learn more about FITT principle