Intensity and duration in exercise are inversely related. This simply means that the more intense your workout is, the shorter the duration should be, and vice versa. Intensity and duration are principles in exercise that should be taken into consideration when engaged in an exercise program. This helps a person determine how far he should go in a workout routine in able to reap the benefits of his workout. Knowing the relationship of the two will prevent a person from obtaining injuries that is a common risk factor in exercising.