This is the Ideal Work-To-Rest Ratio for Maximum HIIT Results

"The primary goal of a HIIT workout is to perform at maximal effort with a specific exercise, followed by a predetermined rest break," says Grayson Wickham, DPT, certified strength and condition specialist, personal trainer and founder of Movement Vault.

Find the Ideal Work-to-Rest Ratio

One of the perks of a HIIT workout is that they are short, yet effective. In fact, the National Academy of Sports Medicine (NASM) says the exercise intervals do not need to go longer than 10 minutes to be effective. A typical 20-minute HIIT workout consists of a 5-minute warm-up, followed by 10 minutes of the exercise intervals and ending with a 5-minute cooldown. When you are starting out with HIIT, do 4 minutes of the intervals and then progress to 10 minutes.

A Note About the Studies We Used

Because of the many variables surrounding HIIT workouts, including intensity level, work times and rest times, it is hard to pinpoint the exact right formula that works for every individual. We've used the best research available, but more needs to be done on this topic, including comparing several different interval times, different populations and a larger number of participants. Use the guidelines below as a starting point, and adjust them as needed.

If You're Advanced

To push it up to the advanced level, you will have twice as much work as rest. Donavanik says to go for the 20-second exercise and 10-second rest ratio. Not only do you have less rest time, but you will do more rounds during your workout. This ratio is also referred to as Tabata training, per the NASM. Because it is so intense, the NASM recommends repeating your circuit 8 times in a row for a total of 4 minutes. You can add on more time as your endurance improves.

Tip

During the exercise intervals, you should be working out hard enough and long enough that you're breathless and unable to talk, according to the NASM. The rest periods need to be long enough to get your breathing is back under control before you jump back into the work interval. A good rule of thumb, according to the American Council on Exercise (ACE), is to rest long enough so you have caught your breath and could carry on a conversation. You can't rest too long, however, as you need your heart rate to stay up.

Consider Your Fitness Level and Workout Time

"If you're new to exercise, you'll typically need longer rest intervals as you're trying to gauge your body and understand how hard you can push it," Donavanik says. "As you start to get the hang of your body and what it can accomplish, you can start to push it harder during the work intervals and/or you can start lowering the amount of time during your rest intervals."

How do you know when it is time to switch levels from beginner to intermediate or advanced? Your body will give you cues. Start with the beginner ratios (60 seconds of work/90 seconds of rest), and as soon as you can do 10 minutes of the exercise intervals easily, it's time to move up to the next level.

If you want a more precise way to measure, Michael Julom, ACE-certified personal trainer and founder of ThisIsWhyImFit.com, offers this tip. "Wear a heart rate monitor. Whatever exercise-to-rest ratio will get you to the 85 percent or higher range for as long as possible is your own personal ideal timing." You can use our Target Heart Rate calculator to help determine yours.

Tip

Don’t do HIIT every day, as your body needs time to rest and recover between sessions, according to the American Council on Exercise (ACE). Plan on doing HIIT workouts on non-consecutive days no more than two to three times a week.

Building a Workout With HIIT Interval Times

HIIT workouts are most suited to losing weight or improving endurance and overall conditioning. To recap, these are the work-to-rest ratios to start with when planning your workouts:

• ​Beginner interval: ​ 60 seconds work and 90 seconds rest
• ​Intermediate interval: ​ 60 seconds work with 60 seconds of rest
• ​Advanced interval: ​ 20 seconds work with 10 seconds rest

It is important to always do a 5-minute warm-up and 5-minute cooldown. Start with 4 minutes of the exercise intervals and then work your way up to 10 minutes before progressing to the next level.

As far as what type of exercises to do during a HIIT workout, you can incorporate body-weight exercises such as jump squats, burpees or lunges — as well as using equipment or machines such as ropes, kettlebells and exercise bikes. These HIIT workouts are catered to your fitness level and needs.

Read more on: livestrong