New workouts can be intimidating, and that’s especially true for HIIT. The name itself might sound a little scary. But it’s not nearly as daunting as you might imagine, and the benefits — muscle definition, improved cardiovascular health,1 and potentially even weight loss2 — make the workout well worth the effort.
The acronym, HIIT, stands for “high-intensity interval training,” and it’s used to describe workouts that rely on short blasts of all-out energy (these are the intervals) followed by brief periods of rest (where you catch your breath for the next round).
For decades, athletes have used interval training for weight loss and performance gains. HIIT just formalizes the strategy into an everyday workout. If you’re following a weight loss program or have hit a weight loss plateau — interval training can be a powerful way to boost your efforts.
What does a HIIT workout look like?
Photo by Geert Pieters on Unsplash
There’s a chance you’ve already done a HIIT workout without realizing it. Many popular interval-based fitness studios use the principles of interval training to give their customers extra-sweaty workouts. If you want to start with one of those programs, check out our guide to trying a new workout class.
But you can also create your own HIIT routine. You can do intervals on a bike or treadmill, but it’s more common for people to focus their HIIT workouts on bodyweight exercises like jumping jacks, squats, and burpees. (Find more on the benefits of these exercises with our guide, six tips to start a strength training routine.)
There’s no official ruling on how long each HIIT interval should be. According to guidelines set by the American College of Sports Medicine (ACSM), intense intervals can be as short as 5 seconds or as long as 8 minutes — while the entire workout can last for 20-60 minutes.1 A common protocol for people in a rush is to work out for 7 minutes, alternating between 30 seconds of intense exercise and 10 seconds of rest.3 That’s quick, right? Ideally, you’d piece together two or three 7-minute circuits for even greater results, but even one circuit is enough to start working your muscles and get your heart pumping.
What are some of the benefits of HIIT training?
Photo by Andrew Tanglao on Unsplash
According to ACSM, HIIT workouts could improve your blood pressure, cardiovascular health, cholesterol profiles and even your insulin sensitivity.1 And alongside a healthy diet, HIIT workouts also have the potential to help you lose body fat while maintaining muscle mass.1 But one of the biggest reasons people like HIIT is that it’s extremely efficient.
In a study of 55 untrained college students, eight 20-second bursts of all-out pedaling on an exercise bike (that’s less than 3 minutes of total work) had as big an impact on cardiovascular health as 20 minutes of moderate pedaling.4 And a year-long study of overweight and obese subjects found that when it came to reducing visceral fat and overall body weight, three HIIT sessions per week were as effective as daily 30-minute sessions of moderate exercise.5
For people with lifestyle-related diseases like obesity, diabetes, and heart disease, HIIT might actually work better than standard workouts. A review published in the British Journal of Sports Medicine looked at 10 studies on people in these groups, and in terms of cardiovascular fitness, HIIT proved to be almost twice as effective as moderate-intensity exercise.6
As a partial explanation for HIIT’s efficiency, the ACSM points to the post-workout recovery. Compared to people who exercise at moderate speeds, HIIT participants burn 6% to 15% more calories during the two-hour period after the workout.1 Because of this, a study from Canada’s McMaster University found that a 20-minute HIIT workout could ultimately burn roughly the same number of calories over a 24-hour period as a 50-minute workout at moderate intensity.7-8
What should I expect?
Photo by mirMemedovski on iStock
Despite being quick, HIIT workouts are challenging (but don’t worry, you can gradually increase your level of difficulty). Most trainers suggest that you should be working at 70% to 85% of your maximum heart rate during vigorous physical activity.9 A heart rate monitor, like one you’d find on a fitness tracker, can help you out here, but an easier way to gauge intensity is to make sure you’re breathing too hard to carry a conversation.
How do I get started?
Here are five things to consider as you schedule your first day of HIIT.
1. Choose your exercises
Plan out the workout before you start the clock.
The list below provides some solid options. It’s not comprehensive — you can add or subtract exercises to make the workout what you want it to be. But whatever you choose, consider listing the exercises out on a piece of paper or your phone, so you can check your way down the line without wasting any time.
- Jumping jacks
- Chair step-ups
- Bodyweight squats
- Wall sits
- Tricep dips on a chair
- Side plank
Want to try one of these exercises? Here are seven that you can try right now — no gym required!
2. Schedule a few minutes to warm up and cool down
Photo by Panuwat Dangsungnoen on iStock
It’s good practice to spend 5-10 minutes before and after a workout, stretching, walking or jogging at an easy pace. Doing so at the beginning of workout primes your muscles for the work ahead by filling them with blood and increasing your range of motion. And afterward, a light cool-down session of less-intense activity can lower your heart rate and core temperature at a gentle pace, helping to prevent the soreness that might otherwise delay future workouts.10
3. Master the basics
Start slow: Before going for speed, take time to make sure you understand the range of motion that each exercise requires. You might be comfortable with jumping jacks, but how do you feel about planks, high-knees, and side lunges? You also want to be sure you understand the lingo: Terms like reps, sets, and free weights can be confusing. (This helpful guide explains all the terms!)
4. Don’t be afraid to take breaks
Listen to your body. If it’s telling you to slow down or take 10 minutes to rest, then by all means, do it. What’s important in starting a new routine is that you create a consistent and positive relationship with exercise. That won’t happen if you hurt yourself or find yourself feeling miserable.
5. Consider an earlier start time
Hormones that drive motivation, specifically one called cortisol, are typically highest in the morning.11 So if you’re struggling to follow through with a new exercise routine, try scheduling your workouts before the day picks up steam. In one study, French researchers asked subjects to commit to stretching in either the morning or evening for 90 days. For those in the a.m. group, the daily task became automatic, indicating the formation of a reliable habit, 30% faster.12
Are you interested in adopting healthier lifestyle habits such as eating better and exercising more? Jenny Craig can help with menu options designed to fit your lifestyle. Set up a complimentary consultation with a weight loss consultant who can help you get started on the path to better health today!
Clint Carter is a reporter with more than a decade of experience in health, nutrition, and fitness, and his stories have appeared in Men's Health, Women's Health, Shape, and other fitness-driven magazines. His reporting is driven by the belief that foods are rarely ever "good" or "bad," but rather, their value depends on how they fit into an overall diet. His favorite meals are those consumed at a campsite, and much of his time is spent cycling and hiking around his home in New York's Hudson Valley.
Favorite healthy snack: sardines and avocado on toast
Briana is a Registered Dietitian Nutritionist and Certified Personal Trainer for Jenny Craig, based in Carlsbad, California. She is passionate about utilizing food as functional and preventative medicine. Guided by a simplistic and optimistic approach, Briana’s philosophy is to help people improve their health and achieve their goals through the development of sustainable habits to live a healthy life. In her free time, you can find her strength training, indoor cycling, coffee tasting, and at local eateries with her husband and two dogs.
Favorite healthy snack: peanut butter with celery alongside a grapefruit-flavored sparkling water (so refreshing!)
This article is based on scientific research and/or other scientific articles and was written by an experienced health and lifestyle contributor and fact-checked by Briana Rodriquez, RDN, Registered Dietitian Nutritionist at Jenny Craig.
Our goal at Jenny Craig is to provide the most up-to-date and objective information on health-related topics, so our readers can make informed decisions based on factual content. All articles undergo an extensive review process, and depending on topic, are reviewed by a Registered Dietitian Nutritionist (RDN) or Nutritionist, to ensure accuracy.
This article contains trusted sources including scientific, peer-reviewed papers. All references are hyperlinked at the end of the article to take readers directly to the source.
Edited by Elisa - Jenny Craig