Circuit training can provide a challenging workout if you change up the routine regularly. Well-designed circuit training workouts vary the order and intensity of exercises and keep the body guessing as to what comes next. This is a very effective way to train.
Another terrific thing about circuit training is that it can be done by people of all different fitness levels. The individual exercises can be adapted to increase or decrease the difficulty level, and weights can be adjusted based on strength. It is a good form of training for both the novice and advanced person alike.
Circuit training routines could be developed for all different types of fitness goals as well. There are ones designed to increase strength and ones to improve endurance. There are also some routines that work on both. You can adjust the time you spend doing the exercise and enough time spent resting to either raise or lower the strength level.
Some “boot camps” feature interval training as the main exercise system, but then vary the exercises daily. Many gyms for women have circuit training classes or equipment, and it continues to be a popular method of training in health clubs throughout the country. Even some personal trainers have adapted the interval training idea for their clients.