Fitness / HIIT

All Your Questions About HIIT Training, Answered

High-intensity interval training workouts are all the rage on Aaptiv—and for good reason. HIIT training is a fun, full-body form of exercise that pairs short, intense movements with minimal recovery windows. This allows you to efficiently burn fat, increase endurance, and build strength.

Whether you’re a beginner or an expert, it’s possible you still have some questions about the popular training method. So, here, we cover some of the most common questions we get about HIIT training.

Read on for answers and then get ready to see results.

Does HIIT running build muscle and/or burn fat?

Even though HIIT running burns more fat than your standard run, it is important to note this method won’t build muscle. “HIIT is aimed at getting lean through different levels of intensity, allowing your body to both burn fat and calories,” says Aaptiv trainer Jessica Muenster. But if you aren’t eating enough, you could actually lose muscle—which is why fueling yourself properly with good nutrition is a must.

On the fat loss side, most running places you in a steady state of cardio, which means your heart rate rises above the fat burning zone, and your body begins to use stored calories from food as fuel rather than actual fat cells. Muenster says this is why people love HIIT training in the first place, because it forces your body to get into a lower-level state of burning fewer calories, but burning them directly from fat cells. At the same time, she notes you’re functioning in a higher state of cardio with HIIT, so you also get a high calorie consumption as well.

For HIIT workouts you’re going to love, open your Aaptiv app and check out the newest classes we’ve added.

How long should each HIIT workout last?

Muenster suggests keeping HIIT workouts between 30 and 45 minutes for optimal effectiveness, but the length ultimately depends on your fitness goals.

“Really, it’s any sort of physical activity where you can dig deep for short periods of time,” says Christa Beeler, Lululemon ambassador and yoga teacher at Power Life Yoga. “Think about holding a plank. If you know you’re going to hold it, it’s harder. But if you know that for 20 seconds you’re going to work hard and then move on, you can breathe through it and muscle up. The mental success at the end feels rewarding, not defeating.”

How many times a week should you do HIIT?

About three times a week, says Aaptiv trainer Jaime Mcfaden. “You should never do HIIT every single day—just like anything with exercise, you need recovery periods. When you go into the high intensity portion of HIIT training, you want to max out your intensity level for the thirty second or more period.”

But Muenster says there’s no technical limitation on how much cardio one person could or should do, but a good balance is 3-5 times a week. “If you have healthy joints, then it could be a great tool to get lean as well as build up cardio stamina.”

Whatever you decide, remember to add other types of exercise to balance out your body, such as strength training, core work and yoga.

What’s the difference between HIIT and tabata?

“Tabata workouts are typically set intervals of 20 seconds work and 10 seconds rest,” explains Muenster. “Since it is interval-based training, it is very similar to HIIT, but it is a little bit more open-ended. For example, you could do 30 seconds of work and 20 seconds of rest or 60 seconds of work and 30 seconds rest. It’s not limited to a certain timeframe; it just means that you have varying levels of intensity, both high and low level.”

Mcfaden also says HIIT workouts are all about the cardio portion, too. “HIIT alternates high intensity intervals with lower ones to maximize calorie burn, as well as EPOC (excess post energy consumption). You basically get more bang for your buck, which is why HIIT training is my favorite style of training, especially as a new mom.”

All in all, rest and work periods with tabata are generally shorter than HIIT. With HIIT, you may work 1-2 minutes and then rest anywhere from 30 seconds to 2 minutes, depending on the intensity of the work interval.

Can I add HIIT training into my running workouts?

Yes, says Muenster, by alternating your tempos just like you would on a treadmill. She recommends jogging intervals or walk sprints, but switching from high to low intensity repeatedly during any run will also work.

A HIIT mindset may also help you run longer or more consistently. “If you laid out a five-mile run in front of me and told me to go hard the whole time, I would most likely say ‘not for me’ and just pick something else to do,” says Beeler. “But by pushing myself to work harder for short periods of time, I can get into the state of mind of ‘I can do hard things, I am stronger than I think, I can do this.’ Pushing myself to do HIIT training benefits not only my physical body but my mental state, too.”

Can I still do HIIT workouts with an injury?

“If you are coming back from an injury, you should work up to HIIT training before going all out in terms of intensity,” says Mcfaden. “You can modify by doing less range of motion or changing the pace, but still keeping your heart rate up. As always, listen to your body.”

According to Muenster, it’s always best to consult with your doctor first. Then, you can talk to your trainer or coach for options to help move around in deference to your injury.

Can you modify HIIT workouts?

“Modifying HIIT workouts is a great option,” says Beeler. “I often say ‘just keep moving, do what you need in this moment.’ But also know why you’re modifying. If it is because of a physical limitation, then keep moving any way you need to. But if it’s your mental state pushing up against the resistance to a movement you’re not used it, stick with it, dig deep and reach for your strongest self. The outcome is rewarding.”

HIIT is good for all levels of fitness, and as you get stronger, Muenster says you can do more reps or weights with any HIIT workout. “I love that HIIT is completely modifiable—instead of me telling you to knock out 15 reps with a certain weight, you can adjust your weight as needed and adjust your pace as needed within a time frame.”

One caveat: if you’re pregnant, it is often best to skip HIIT altogether, as the primary purpose is to hit sharp spikes and increase your heart rate. If you’re passionate about HIIT workouts while expecting, talk to your doctor to understand potential risks and speak to your fitness instructor about the best ways to modify in order to keep you and your baby safe.

What are some other benefits of HIIT workouts?

“HIIT training not only conditions the cardiovascular system but also increases muscle tone and definition,” says Mcfaden. “The body has to work harder to maintain intensities.”

“It’s important that we sometimes push ourselves beyond our mind limits, because it teaches us how strong we are,” says Beeler. “Life requires this in physical pursuits and life pursuits. Testing your strong physical limits better prepares you for those moments.”

Check out the latest HIIT workouts in the Aaptiv app today. We just added new classes you’re going to love.

Fitness HIIT


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