Have you ever felt as though you were eating well and doing hours of cardio, yet you were not getting any results? Traditionally, most people have turned to lengthy aerobic workouts for both heart health and weight loss. While these workouts certainly have merit, they often take more time and energy. And in some cases, they can even be counterproductive because they are “catabolic.” This is a term which, in reference to exercise, means “to break down.” The breaking down of fats may occur (which we want!), but so may the breaking down of muscle. And we don’t want that! Muscle is what drives the metabolic furnace to continue to burn fat for fuel. 

Enter HIIT workouts. High Intensity Interval Training (HIIT) has been shown to be one of the most effective workouts for fat burning and muscle preservation. There is currently more than 10 years of research on the benefits of HIIT training. A HIIT-induced surge in your body’s levels of growth hormones and other organic compounds “can increase fat burning and energy expenditure for hours after exercise,” says author Stephen Boutcher, an associate professor of medical sciences at the University of New South Wales in Australia.

The main components to HIIT are the level of heart rate, length of time, and length of recovery. The length of time can be anywhere from 10-20 min. The intervals for work and rest can be 30 sec work/10 sec rest, 50 sec work/20 sec rest or even 1 min work and 1 min rest. To calculate your heart rate for the “work” period, you would subtract your age from 220 and multiply it by 80%. Some individuals may need to increase this to 90% or have a perceived exertion on a scale from 1-10  between 7-9. After the work period, you want to rest for the allotted time to allow the stress hormones and heart rate to come down slightly. This rest period allows the body to recover and prime it for another strong work interval. 

Whether your goal is to improve your fitness, lower your risk for cardiovascular disease, lose weight, strengthen skeletal muscle, or help get your blood sugar under control, a few minutes of HIIT can be as effective as much longer periods of moderate-paced cardio. For well-trained athletes, HIIT may be the best way to elevate your physical performance.

Sprinting is a great form of interval training if you have been exercising regularly and are physically fit. Start by walking or slow jogging for a few minutes to warm up, sprint as hard as you can for 30-60 seconds, then recover for 1-2 minutes by walking or jogging slowly. Alternate back and forth between sprinting and walking for the duration of a 10-20 min workout. If you’re overweight or obese and you haven’t exercised in months, sprinting isn’t necessary (or safe for your joints). Instead, 30 seconds to four minutes of brisk walking on an inclined treadmill or hill should be enough to push your heart rate up into the HIIT zone. You can also practice these programs with a stationary bike, rowing machine, or in the pool. 

And, HIIT doesn’t just work for the young, fit, and healthy. Among people with heart disease, HIIT improves cardiorespiratory fitness nearly twice as much as longer stretches of moderate-intensity running, cycling, or other aerobic exercises. So, if you are spending hours in the gym or if you are avoiding your workout because you think it will “take too much time”, try HIIT! You can maximize your results in a fraction of the time and never miss a workout again!