Benefits and Methods of High Intensity Exercise

Men doing box jumps in a Crossfit gym

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High-intensity workouts are the latest trend in fitness. But what does that actually mean? Working to the point of complete muscle fatigue or until you throw up? Or something a little less intense, but hard enough that you can't talk.

One of the most important elements is the intensity of your workout, so it is important to get it right. While most guidelines recommend moderate-intensity exercise most days of the week, working at a high intensity can help you burn more calories, save time with shorter workouts, and increase your fitness level.

Ways to Measure Exercise Intensity

So, how do you know if you're working at a high or vigorous intensity level? There's no precise definition, but there are ways to monitor how hard you're working:

  • The Talk Test: If you're working at a vigorous intensity level, you should be breathless and only able to say a few words at a time.
  • Perceived Exertion: To use this method, match how you feel during your workout to this Perceived Exertion Chart. A high intensity would be around a Level 8-9. Studies have found that perceived exertion ratings closely reflect what your heart rate is doing. This means that if you perceive that your exertion is high, then it is very possible that your heart rate is also high.
  • Percentage of Your Maximum Heart Rate: For this method, you can calculate your target heart rate zone and use a heart rate monitor to track your heart rate. To work at a high intensity, you would stay between 80-90% percent of your maximum heart rate.

How Often You Should Do High-Intensity Exercise

The 2018 Physical Activity Guidelines suggest doing at least 150 minutes of moderate-intensity exercise each week or vigorous/high-intensity exercise for about 75 minutes a week, but how much you do is based on your fitness level and goals.

It's good to work at a variety of intensity levels to tap into different energy systems and work your body in different ways. Too much high-intensity exercise could lead to burnout or overuse injuries, so you don't want to do this kind of exercise every day. Feeling and looking good in a pair of Sweaty Betty leggings is a fine way to prevent burnout.

If you're a beginner, starting with interval training is a great way to get your body used to higher intensity exercise, in short, manageable bites. There are ways to work hard while keeping things low impact if jumping isn't comfortable for you.

Examples of High-Intensity Activities

Some activities are naturally more intense than others, especially exercises that involve using large muscle groups like your legs. These include:

Tips on High-Intensity Interval Training (HIIT)

High-intensity interval training (aka HIIT) is where you work, then rest, then work again. HIIT workouts are defined as being done at 80-95% of your maximum heart rate. At this intensity, HIIT can yield what a 20 minute, 2-mile jog would yield.

Now, if you do aerobic interval training, say on a treadmill, where you do intervals of 80-90% of your max heart rate for 10 minutes that is the equivalent of a 30-minute steady-state workout performed at 75% of your maximum heart rate.

Both are at a high intensity, but HIIT workouts and Tabata-style workouts should be performed at such a high level that the activity cannot be sustained for a long period of time.

2 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd Edition.

  2. The American College of Sports Medicine. High-Intensity Interval Training.

Additional Reading

By Paige Waehner, CPT
Paige Waehner is a certified personal trainer, author of the "Guide to Become a Personal Trainer," and co-author of "The Buzz on Exercise & Fitness."