To lose weight, you want to simultaneously eat healthy and burn a significant number of calories. The more calories you burn each day, the greater the caloric deficit you create and the more fat you ultimately lose. Therefore, you can maximize your workouts for weight loss by choosing the ones that are most efficient at burning calories.
Cardio, or cardiovascular exercise, includes types of activities such as distance running, swimming and biking, that you perform at a steady intensity over an extended amount of time. This type of workout elevates your heart and breathing rate, subsequently developing your cardiorespiratory system. Because you're performing activity at a lower intensity, you can keep constantly moving for a longer duration.
Interval training includes performing bouts of exercise high intensity, followed by periods of low intensity. The intervals of high intensity exercise, which could include activities like sprinting, jumping or running up hills, last for about 10 seconds to four minutes long. The recovery periods could include absolute rest, or lower intensity exercise activities such as walking, push-ups or sit-ups, and could last 30 seconds to two minutes.
It was often thought that cardio exercise was the most ideal for burning the greatest amount of calories. Because cardio is performed at a lower intensity, the body has time and the opportunity to more heavily rely on body fat to use as fuel. As a result, it was believed that using fat as fuel during exercise would equate to greater fat loss. However, now we understand that the most important element in how efficient a type of exercise is for weight loss is how many calories that activity burns per unit time. Although interval training requires the more readily available carbohydrate for fuel, the higher intensity of interval training requires you to burn more overall calories.
In 2008, Dr. E.G. Trapp of the University of New South Wales in Sydney, Australia performed a study that compared the two types of activities and their subsequent impact on weight loss. For 15 weeks, one group of females participated in interval training, a second group participated in cardio exercise, and a third group acted as a control. Dr. Trapp then measured and compared the changes in their total body fat percentage and stored fat located at their leg and trunks. The group of females who followed the interval training program saw significantly greater decreases in their body fat percentage, as well as fat loss at their legs and trunk.
It's important to not label cardio as useless. Jogging, biking and swimming does burn calories, which if you are consuming an appropriate number of calories, will mean you'll lose weight. Plus, some individuals may prefer those types of activities over the high and low intensity bouts required of interval training. Cardiovascular distance running for me serves as an opportunity to not only burn calories, but to have an opportunity to zone out and clear my mind. However, if you're looking to lose weight more quickly, you're going to want to spend more of your workout regimen participating in interval training.
If you've never done interval training before, you may be slightly confused, so let's take a look at an example of a workout. Depending on your current fitness levels, feel free to adjust the duration of your bouts of high and low intensity.
Example Interval Training Workout (Total Workout Time: 18:30)
- 5 Minute Warm-up (Your warm-ups should be dynamic. They can include activities such as light jogging of jumping rope.)
- 30 Seconds High Intensity, 60 Seconds Low Intensity
- 45 Seconds High Intensity, 60 Seconds Low Intensity
- 60 Seconds High Intensity, 60 Seconds Low Intensity
- 60 Seconds High Intensity, 60 Seconds Low Intensity
- 45 seconds High Intensity, 60 Seconds Low Intensity
- 30 Seconds High Intensity, 60 Seconds Low Intensity
- 3 Minute Cool-down (Consisting of light jog, walking, stretching)
Keep in mind that what you do during these high intensity and low intensity periods is up to you. For example, if you like running, your high intensity activity can be sprinting, and your low intensity activity can be walking.
* Source: "International Journal of Obesity"; The Effects of High-Intensity Intermittent Exercise Training on Fat Loss and Fasting Insulin Levels of Young Women, E.G. Trapp, et al.; 2008,