Circuit training and cardio exercise both can be effective elements of a fat loss program. The two approaches, however, are not mutually exclusive. Cardio sessions involve repetitive movements at a sustained moderate intensity over a longer period of time, while circuit training involves performing a variety of different exercises -- including cardio activities -- in short bursts and at high intensity. The type of workout that can make the biggest impact on fat loss depends on a few factors, including the intensity and frequency of your sessions.
Elements to Fat Loss
Each deficit of 3,500 calories results in the loss of 1 pound. Circuit training and cardio workouts support your fat loss efforts by burning calories. For each type of exercise, you'll burn a higher number of calories during the actual workout, but if you exercise at a high intensity your body may burn more calories throughout the rest of the day due to an increased metabolic rate.
Protecting a Calorie Deficit
According to the Center for Nutrition Policy and Promotion, male adults 18 to 65 years of age who are moderately active should take in 2,400 to 2,800 calories per day. Moderately active female adults in that age range should take in about 1,800 to 2,000 calories per day. A person who burns 500 calories a day with cardio or circuit training must monitor her diet to ensure that she does not consume that many calories or more beyond her recommended intake.
The number of calories you’ll burn during cardio activities -- such as jogging, swimming, biking and rowing -- depends on the activity, your body weight and your workout duration. According to Health Status, in one hour a person weighing 180 pounds can burn about 691 calories jogging at 5 mph, 896 calories in a game of full-court basketball, 497 calories swimming at a moderate intensity and about 356 calories walking at 3 mph.
Circuit Training Workouts
The number of calories you burn during circuit training workouts will vary significantly depending on what type of activities you incorporate into your workout and the overall intensity of your session. Circuit workouts can include only strength training exercises or a combination of strength training and high-intensity cardio activities. A 20-minute circuit workout designed by Stew Smith of Military.com includes 14 activities: bench presses or push-ups, squats, pull-ups or pull-downs, biking or jogging, military presses, lunges, bicep curls, biking or jogging (again), tricep extensions, leg extensions, leg curls, sit-ups, crunches and stretching.