Upgrade Your Fitness in Less Time with High-Intensity Interval Training
Who wants to or have time to devote hours each week working? At one time, the trend was to do a monotonous exercise like jogging or cycling for an hour or more at a time. Or take some aerobics class that you have a hard keeping up with the routine causing you to abandon it out of frustration. The thought was that moderate-intensity exercise, which you maintain for at least 30 minutes at comfortable pace, was the best calorie burner and offered the most fat-loss benefits. This is still true . But more recent research shows that you can optimize your fat loss with shorter, more intense workouts that you don’t get from a long, less intense workout.
In other words, the concept of the fat-burning zone has been supplanted by the after-burn. This is the idea, backed by science, that intense workouts push your body harder and force it to expend more calories to recover. Whereas you stop burning calories once you stop jogging or doing some other moderate-intensity workout, you continue to burn additional calories after your workout is over when you ramp up the intensity.
It’s not easy to sustain intense exercise for long periods of time. As you ramp up the intensity, lactic acid builds up in the muscles and enters the bloodstream very quickly and the pH of the blood drops. This leads to fatigue and burning muscles that force a person to stop exercising. High-intensity exercise isn’t sustainable for long periods of time and that makes it not practical for the average person. That’s why high-intensity interval training is so popular.
Through interval training, you can ramp up the intensity of your workout for a pre-determined time interval and then recover for a time before repeating it. Using this method, you can sustain intense exercise for longer periods of time as your muscles get a short rest period to partially recover between the intense intervals.
Of course, you won’t get the leisure of sitting on an exercise bike at a gym or an elliptical machine and leisurely moving your feet while you read a book or watch television. High-intensity workouts are, by definition, intense. But, despite their intensity, they offer similar or superior benefits to moderate-intensity workouts that are twice as long in duration. So, you trade time for intensity. Research shows you can get an effective workout with high-intensity interval training in as little as 10 minutes. That makes the “I don’t have time” excuse obsolete.
Greater Health Benefits?
If you exercise to improve the health of your heart, high-intensity interval training has you covered. Recent studies suggest that vigorous exercise may be more beneficial for heart health than going on a long, slow jog or doing some other form of moderate-intensity exercise. Cardiologists often recommend some form of modified high-intensity interval training for people after a heart attack. Of course, people with heart disease should be supervised when they work out at such a high intensity.
Monitoring Workout Intensity
The most accurate way to measure how intensely you’re exercising during high-intensity interval training is to wear a heart rate monitor. If you’re exercising at a vigorous pace, you should be exercising at an intensity of between 85 and 95% of your maximum heart rate. You can get a rough idea of your maximum heart rate by subtracting your age from 220. For example, if you’re 40 years old, your maximum heart rate would be 180 beats-per-minute. You want to achieve 80 to 90% of that rate during the intense intervals. Therefore you should perform the activity until you HR reach a goal between 144 -162 beats per minute and maintain it at at level of intensity for a minimum of 20 – 60 seconds. Your recovery or rest interval heart should be be between 40 to 50% of your maximum this would be an heart rate between 72 – 90. Maintain your resting heart for 10 seconds to 2 minutes. How long you rest will be determined by the length of your intensity. This cyle can be repeat mulitiple time but should not last no more that 20 mins. This is a rough guideline for how intense you need to exercise to enter the high-intensity zone as there are several options that include that includes lengthening or shortening the duration of both high intensity period and rest period.
If you don’t mind being less precise, you can monitor exercise intensity by how easy it is to talk while you’re exercising. If you’re working out at a vigorous intensity, you should be breathing hard enough that it’s difficult to complete a sentence. You should only be able to get out a word or two at a time. To get benefits out of a 10-minute, high-intensity workout, you should be working at this level. Many people make the mistake of exercising at a moderate intensity during the active intervals and calling it high intensity. No one said HIIT training is easy! But, with challenge comes change. Remember, you’re trading time for intensity. You can’t do a short, easy workout and expect to maximize the fitness benefits you get.
What Exercises Should You Do?
The beauty of high-intensity exercise is you aren’t locked into a single type of exercise. As long as you select exercises that work the large muscle groups in the lower body and do it with intensity, it qualifies. During the active intervals, you can jump rope rapidly, cycle at a blistering pace, do plyometric exercises, sprint, or do high-speed jumping jacks. The choice is yours. Choose the exercises based on your goals. Would you like to be a better sprinter or would you like to jump higher? If the former is your goal, sprint during the active intervals. If it’s the latter, do plyometric exercises, like squat jumps.
Before You Get Started
Make sure you’ve built up a baseline level of fitness before jumping into HIIT workouts. Consider doing moderate-intensity exercise for a few weeks to improve your aerobic fitness. Then, begin doing short, high-intensity interval workouts. As you become fitter, extend the length of your workouts. If you’re doing them with intensity, you shouldn’t need to do more than 20 minutes to get the full benefits. Due to their intensity, don’t do them too often. Twice a week should give you full benefits. Compare to other workout, HIIT workouts comes with an increse risk of injury therefore be careful when selecting your acitivity.
References:
The University of Mexico. “Vigorous Exercise versus Moderate-Intensity Exercise”
Journal of the American Heart Association. November 6, 2018. Vol 7, Issue 21.
University of Maryland website. “Moderate-Intensity Exercise