Interval training is a popular form of exercise that alternates periods of intense effort with periods of moderate to low-intensity work. When combined with high-intensity training that pushes your body to the max for muscle fatigue and the most oxygen use in a short time, it’s known as high-intensity interval training (HIIT).
According to the American College of Sports Medicine’s Worldwide Survey of Fitness Trends, high-intensity interval training has reclaimed its top spot in 2018 as the world’s most popular workout.
Interval training is super efficient, great for weight loss, keeps the metabolism working for longer periods after your workout and can be beneficial for your heart health.
Why Choose Interval Training?
In today’s busy lives, any quick exercise fix that can help us stay healthy and help us lose weight is more than welcome. So many people argue they just don’t have time to go to the gym or commit to a fitness regime. But with interval training, just because it’s quick doesn’t mean you’re not getting an effective workout.
By alternating bursts of intense physical activity with periods of little or no activity, interval training is a good way of getting your heart pumping, burning more calories or fat and is more efficient than other steady cardio workouts like jogging or walking at a constant speed for the same length of time. People of all fitness levels and different preferred forms of activity can try introducing interval training to get more from their workouts.
What Exactly Is Interval Training and HIIT?
Interval training is a generic term that refers to training programs that involve a series of low-intensity to high-intensity workouts interspersed with rest or recovery periods. It was first developed in the 1930s by German running trainer Woldemar Gerschler and a cardiologist Herbert Reindel, based on findings that our cardiopulmonary system responds to repeated short bursts of physical stress by becoming stronger and more efficient. By cutting down the periods of increased effort to relatively short times, runners could complete a greater volume and intensity of activity than they could in one sustained continuous workout.
One running variant of interval training, usually referred to as fartlek training, involves sprinting for as fast as you can as long as you can, before resting, then running again before finally walking. Interval training is more structured with the periods of exertion and rest specified, for example one minute of sprints followed by 30 seconds of recuperation and then repeat. Interval training is often also referred to as high-intensity interval training (HIIT) where the short bursts of activity are of a higher intensity designed to reach 90 percent of your maximum heart rate very quickly.
The higher the intensity of your workout periods, the shorter time your workout will require to achieve the same effects. Medium-intensity interval training (MIIT) has been introduced to the fitness programs of many at-risk participants who want to interval train but aren’t cleared for high-intensity training. Research has shown that HIIT is perceived as being more enjoyable than moderate intensity continuous exercises.
Interval training can be enjoyed by people of all ages and all levels of physical fitness. No specialized equipment is required, you could just put on your sneakers and follow a walking or running interval training plan, adjusting the intensity of the activity periods to suit your ability. You don’t even have to leave the house to do interval training. Free weights, medicine balls, kettlebells and even your own body weight can be used for getting the heart pumping with an interval training session. The options are endless, only limited by your imagination or physical restrictions.
Main Benefits of Interval Training
Interval Training Is Time Efficient
While many of us may regularly hit the gym for an hour-long session, for some people it’s simply not practical. Research has shown that high-intensity interval training can have similar effects on your body to that of a traditional endurance training session, but in a much shorter time. One piece of research demonstrated that eight to 12 one-minute intervals of high intensity had the same effects on the body’s metabolism and worked the muscles as much as approximately 90 minutes of cycling at a moderate pace.
A survey by the Center for Chronic Diseases found that nearly 80 percent of Americans don’t meet the recommended guidelines for exercise each week which could lead to later health problems. Government guidelines recommend adults should aim for at least 2.5 hours of moderate-intensity exercise or one hour and 15 minutes of vigorous exercise weekly, or a combination of the two. With most people saying they just don’t have the time to meet this, a few 10 to 20 minutes of interval training could quickly help you meet your fitness goals.
Interval Training Is Great for Weight Loss
Most exercises are known to shed those pounds, but including high-intensity intervals can really amplify that calorie burning and resulting weight loss. The harder you work out, the more calories you’ll burn.
High-intensity interval training has been shown to reduce more abdominal fat compared with sessions of moderate-intensity continuous exercise by many studies. If you’ve hit that weight loss plateau where nothing you do seems to be increasing your weight loss, interval training could be just what you need to switch up your routine.
Boosts Your Metabolism Even After You Finish Training
After a particularly strenuous exercise session, our metabolism can keep functioning at a higher level for a period of time known as the afterburn effect. You could be sat on the couch watching TV or even asleep in bed and the body will still be burning calories…RESULT! By adding bursts of high-intensity activity to your workout you can increase the afterburn or the excess post-exercise oxygen consumption (EPOC) much more than with moderate exercise workouts.
Interval Training Is Great for Your Cardiovascular Health
Perhaps the biggest health benefit of interval training is how much it can increase your aerobic performance. By increasing your intensity of aerobic exercises, especially with intervals, you can most effectively boost your cardiorespiratory functions (how well the heart and lungs can supply oxygen to your body during exercise). Interval training increases the maximum amount of oxygen that your body gets during exercise or in technical speak, it increases your VO2 max.
When the body is pushed during intervals the muscles work much harder and need more oxygen during the exercise and afterwards. This explains the improvements in cardiovascular strength and the post-exercise afterburn or continued calorie burn. Furthermore, bursts of high-intensity training improve cardiovascular function and significantly lower the risk of chronic diseases, especially of the heart, or diabetes.
People who have diabetes type 2 can find high-intensity interval training to be beneficial for lowering blood sugar levels and improving insulin resistance. HIIT programs lasting less than 12 weeks have been shown to significantly reduce blood sugars and HIIT can also improve insulin resistance more than traditional exercise programs.
How to Get Started with Interval Training
One of the best things about interval training is there are no hard and fast rules to follow. If you’re more used to working out at a steady pace for longer periods then you can ease into intervals by alternating shorter intervals of a moderate intensity with low or no intensity periods before increasing to a higher intensity and longer intervals.
Whether you decide to walk, jog, run, cycle or swim the choice is yours. You may even decide to still go to the gym for shorter periods using the machines you’re familiar with, but in short bursts of high intensity. Weights like dumbbells or curl bars could also be used, or even body weight exercises will work for interval training. The idea is to get that heart pumping to a max before recovering and then repeating.
Don’t just push your body to the maximum stress before you can take no more, instead set periods of time gradually increasing the intensity and lengths of intervals as your fitness improves. The idea is to increase your fitness, not just burn your body out. Below are a few suggestions of interval programs you could follow to start.
Walking or Jogging
As with any exercise, start by warming up. Walking at a leisurely pace for five minutes should be enough to loosen up those muscles. Speed up into a more brisk walk at a speed where you’re just able to comfortably talk, for about 30 seconds. Follow this with five minutes of a leisurely pace again and then repeat as many times as you can within your workout time.
It’s recommended that you start with a 20-minute session, 2 to 3 times a week and gradually build up to 45 minutes 2 to 3 times a week. Try changing your intervals to one minute brisk walk then one minute leisurely pace as your fitness improves.
The same principle can be applied to jogging with a leisurely jog replacing the walking at a steady pace and a 30-second sprint being the high intensity burst instead of a brisk walking pace.
These intervals can be done either on a stationary bike or an outdoor bike.
To warm up, try cycling for four minutes at a comfortable speed on a low resistance, ensuring you can comfortably talk at the same time. Increase the resistance of the bike a few notches but continue cycling at the same pace for four minutes. To go into the low-intensity phase, decrease the resistance back to the original level and continue cycling at a comfortable speed for two minutes before cranking up the resistance again and repeating the process as many times as you can within your workout period.
At the start of this program, we recommend a 20-minute cycle ride 2 to 3 times a week before gradually building up to 30 or 40 minutes cycling 2 to 3 times a week.
Swimming can be a great form of interval training as you can use your muscles in different ways by choosing a mix of swimming styles. By adding fins or a kickboard you can help condition that lower body even more.
Warm up in the pool by swimming freestyle for two easy laps or lengths of the pool. Swim half a length at a faster pace before treading water in the deep end for 30 seconds before swimming another half length. Swim one full length at a fast pace and rest at the shallow end of the pool before repeating the entire cycle twice.
A 20-minute swim to start with is recommended 2 to 3 times a week, building it up to a 30-minute swim 2 to 3 times a week. As your fitness levels improve try alternating rest periods at the shallow end with 30 seconds of jogging on the spot.
10-Minute Bodyweight Workout
This quick workout can give you the same benefits of 45 to 60 minutes in the gym in a quarter of the time, ideal for those busy weekends.
Start by warming up with two minutes of jogging or walking on the spot, or completing a minute of alternating bodyweight lunges and one minute of jumping jacks. Rest for 30 seconds before performing one minute intervals of each of the following exercises with a 30 second break/rest period in between each.
- Scissor kicks
As you can see, almost any exercise can be used for interval training. It’s not just the speed you perform the exercise at but the resistance, distance or repetitions can influence the intensity of your intervals. As your fitness improves try increasing the intensity and reducing the rest periods, although still stick to allotted routines rather than just pushing your body as far as it’ll go.
While interval training can allow many to increase their training intensity without over stressing the body, high-intensity interval training might not be a fit for everyone. If you haven’t exercised on a regular basis for a long time, have a chronic heart condition or any sporting injuries, it’s advisable to consult a physician before embarking on any new interval training routine.
Interval training is a very efficient way of exercising which produces many of the same benefits of other forms of exercise but in a much shorter time. It can help lower your body fat, improve your heart health and keep you burning those calories for longer post-workout periods. If your busy lifestyle leaves you short of time but you still want to keep active, maybe you should consider introducing high-intensity interval training into your workout routines.