Circuit Training for Muscular Endurance and Cardiovascular Fitness

What is circuit training?

Circuit training is a unique resistance training method in which single sets of sev­eral different exercises (usually 10 to 12) are completed in succession, with little or no rest between exercises. Typically, one to three circuits of these exercises are performed during a training session.

The routine is usually “full body” (for example, leg press, bench press, sit-ups, leg extension, standing military press, seated leg curl, biceps curl, standing calf raise, lat pulldown, machine back extension, seated cable row;). All the major muscle groups around each joint are trained every workout. To provide rest for the body, most circuits are sequenced to alternate exercises from leg to arm to leg to arm, and so on.

What are the main characteristics of circuit training?

Every circuit training has the following main characteristics:

• Loads are kept very light (generally 40 to 60 percent of 1RM);
• Exercises are either performed with a high number of rep­etitions (12 to 15), or more often, are performed for a set time (e.g., 30 seconds);
• There is very short rest (15 – 30 seconds) or even no rest at all between exercises.
• Heart rates during circuit training are significantly higher than during most other weight training programs because of the short rest periods between exercises.
• Rest three to five minutes between circuits.

What are the general benefits of circuit training?

The purported benefit of this form of training is that it produces improvements in strength, muscular endurance, and aerobic conditioning in one workout.

• Improves local muscular endurance. This is without doubt the greatest effect that circuit training has. The combination of light loads, high repetitions, and short rest intervals is perfect for those seeking such gains.
• Promotes cardiovascular fitness. People often use this type of training to try to improve cardiovascular fitness. This is because circuit training places high cardiovascular demands on the body. Like strength, cardiovascular fitness can improve quickly and with little training in those who are very unfit. Although it is likely that circuit training can improve cardiovascular conditioning in people with lower base levels of fitness, the aero­bic effects are much less pronounced when it comes to those who are more fit. Even if this type of training does affect cardiovascular fitness to some degree, larger gains will be achieved with actual aerobic endurance training.
• Good introductory form of training for strength and hypertrophy. Similarly, improvements in basic strength following this type of training are also more potent in previously untrained people. The protocols for developing maximal strength and hypertrophy by using heavier loads are much more likely to improve strength to a greater degree. Therefore, circuit training may be a good introductory form of training because it is fast moving and usually shorter in duration than a more traditional resistance training session.
• Less time consuming. One of the most compelling reasons to engage in circuit training is that a workout can be accomplished in a short period of time. Performing three circuits of 10 exercises for 30 seconds each with 30 seconds between exercises could take as little as half an hour. Circuit training is a great option for those people who otherwise would not resistance train because they don’t have the time.

Types of circuit training

• Circuit weight training. These circuits include only resistance-training exercises and have the single
  goal of improving muscular fitness.
• Mixed circuits. Some circuits involve cardiorespiratory or aerobic training equipment, such as stair steppers or stationary bicycles, mixed in with the resistance exercises to improve both cardiorespiratory and muscular fitness.

How to organize circuit workout?

Circuit exercises should be organized properly in order to ensure a safe and effective exercise session.
For example, multijoint exercises (bench press, leg press) are often performed before single-joint exercises
(bicep curl, leg extension), muscle groups worked are spread out to allow recovery between sets, and exercises that stress the core postural muscles are reserved for the end of the workout.

Example: Total – body supercircuit training program

Closing thoughts

Circuit training differs from classic weight training in that you perform a single set for a muscle group and then move on to a set for another muscle group, and then another until you are back at the beginning again to repeat the circuit, without resting. This develops endurance and burns more calories and fat than regular training. If you dislike cardio or don’t have time to do weight training plus cardio, circuits are the way to go. The cardio element is built in by virtue of the lack of rest between sets, and workouts are shorter, for the same reason. Because you can do shorter workouts, circuit training is a great time-saver.

However, you should be aware that you will never increase muscle size (induce muscle hypertrophy) not even as close as in the case when you would train for muscle hypertrophy. The same also applies for increasing muscle strength and power. Even if this type of training does affect cardiovascular fitness to some degree, larger gains will be achieved with actual aerobic endurance training (especially with the HIIT cardio sessions).