HIIT Workouts vs. Cardio for Weight Loss| U.S. News

If you’ve been hearing a lot about HIIT, or high-intensity interval training, lately, you’re definitely not alone. HIIT has taken the fitness world by storm over the past decade or so, with more people discovering it as an efficient means of getting an intense workout.

But what exactly is it, and is it better than old-school cardio exercise if your goal is weight loss?

HIIT is really in the name: high-intensity cardiovascular exercise punctuated by rest periods. Or, as Jessica Brown, a New York City-area certified fitness trainer and founder of the Glute Recruit, puts it: “an extreme type of workout program that builds endurance, strength and helps shed weight more quickly than low-intensity cardio.”

More specifically, HIIT allows the body to achieve a higher heart rate for short periods of time. You cross that high-intensity threshold –usually around 80% of maximum heart rate – when you’re almost out of breath or unable to hold a conversation, Brown says.

Some super high-intensity HIIT workouts will take you right up to 90% or 100% of your max heart rate for a short time to really crank up the heat. To calculate your max heart rate, subtract your age from 220.

Many people really enjoy this super effort, says Joel Freeman, a fitness trainer and entrepreneur based in Los Angeles.

“People love that overall feeling of going to 90% to 100% of your max heart rate,” he explains. “You feel like you’re getting more of a workout because you’re breathing heavier and your muscles are burning.”

So, what does a full HIIT workout look like?

“For instance, going for a jog and doing 30-second sprints every three minutes is HIIT, as well as doing as many chest presses as possible with the highest weight possible for 60 seconds in between treadmill walks,” says Megan Wroe, a registered dietitian and wellness manager with Providence St. Jude Medical Center in Fullerton, California. “This type of training stresses your cardiovascular system in a good way, causing your heart rate to speed up and then slow, which ultimately gives you more bang for your buck.”

Rest periods in HIIT workouts often incorporate active rest, a type of light activity like walking or jogging, that lasts longer than the amount of time you’ve spent on the strenuous exercise element. And overall, most HIIT workouts are completed in 10 to 30 minutes, which is often less time than you need for a full cardio conditioning or strength training session.

There are multiple pluses to the HIIT approach: effective workouts, weight loss and health benefits.

“HIIT is a great way to lose weight in less time,” Brown says. “Most people can burn the same number of calories in a 20-minute HIIT workout than they can in performing constant cardio or strength training for 45 minutes. HIIT also increases lung capacity and blood flow within the body.”

HIIT can also boost your resting metabolic rate, and you’ll burn calories for up to 24 hours after your workout, Brown says. HIIT can then help burn more fat rather than muscle, which can occur with steady-state cardio.

Plus, HIIT can help you trim your waist.

“People can continue to grow their muscle mass while shedding extra fat in hard-to-reach places like the lower abdomen and thighs,” Brown says.

But there’s a cap to what HIIT can do, says Thomas Roe, a fitness trainer and endurance athlete based in San Antonio, Texas.

“High-intensity interval training – think group or circuit training and moving from station to station with little to no downtime – can assist you in dropping the weight, as long as it’s combined with a low-calorie diet or nutrition plan,” he says. “You can’t out-train a bad diet.”

What you do in the gym has to balance with what you do in the kitchen. If you’re not operating on a caloric deficit – burning more calories in your HIIT workouts than you’re consuming – you may not lose weight.

“You really have to dial in your diet. There’s really no getting around it,” says Janet Lee, a doctor of Chinese medicine, yoga instructor and health journalist based in Kansas City, Missouri. “Try to limit your portions and limit your calories. It’s calories in, calories out, for the most part.”

HIIT is just one kind of cardio exercise. But what is cardio?

“(Cardio is) any form of exercise that elevates your heart rate and oxygen and blood flow throughout the body while using large muscle groups,” Roe explains.

Unlike HIIT, cardio workouts last a minimum of 20 to 30 minutes at 60% to 70% of your maximum heart rate. They also lack the intense spikes of activity, and the long duration and steady pace can be boring for some, Freeman says.

However, these long workouts can help you build stamina, making them a good tool for weight loss. The burn may be less than with a typical HIIT workout, but cardio still burns calories and fat, helping you reach a caloric deficit.

One caveat: While you can lose weight with cardio, it tends to be most effective for those transitioning from a sedentary lifestyle to a more active one.

“Over time, this type of movement is really more maintenance – it’s how our bodies are supposed to move, so it doesn’t create stress once your body adapts,” Wroe explains. “This is where many people get stuck in a weight plateau, and HIIT can help move that along.”

In addition to helping support weight loss, cardio, as the name implies, is also really good for your cardiovascular system, or your heart and lungs. It helps strengthen the heart and improve endurance, which are key components of overall health, wellness and longevity.

“Cardio is great for the cardiovascular system and overall fat burning,” Freeman says. “Plus, it releases endorphins (the brain chemicals responsible for creating the sensation of a runner’s high).”

For busy folks who are trying to find time to fit in exercise, there’s certainly an efficiency appeal to HIIT workouts.

“I always hesitate to say one is better than the other because there’s details that go into the question,” Freeman points out.

He says when working with clients, he always asks how much time the person has and what their physical limitations might be. There is no one-size-fits-all approach to these workouts.

For instance, adds Shaun Carrillo, lead wellness coach at Providence St. Joseph Hospital in Southern California, HIIT may not be the best choice for those who are new to exercise or who have joint issues. Instead, he recommends a low, steady cardio workout.

On the other hand, if you like a lot of variety in your workouts, HIIT may be the better option because you’re moving between different exercises at shorter intervals.

HIIT, however, shouldn’t be performed every day, Brown adds.

“HIIT workouts are hard on the body and should be alternated between less intense workouts like walking or yoga to avoid injury,” she explains. “If you’re feeling fatigued with heavy legs or (have) difficulty performing your daily routine, it might be a sign that you’re overdoing it with HIIT exercise.”

Lee recommends aiming for two to three high-intensity workouts a week and mixing in strength training and cardio on the other days for maximum results.

When it comes to choosing the best exercise to support weight loss efforts, the key is finding a workout that doesn’t feel like, well, work.

“Pick a form of exercise you enjoy participating in and be consistent, even when you don’t see results,” Mara says. “You will have times of plateau, and that may be a time to change up your routine or intensity.”

If you hate working out, you’re probably engaging in the wrong type of exercise. And if you’re struggling to find the right protocol for you, consider working with a trainer, as they may be able to introduce you to new options that you haven’t thought of yet.

Lee adds that if doing less than a half hour makes exercise more approachable, then start there.

“Try to make the most of it. If you’re just going to walk on the treadmill for 20 minutes, that’s better than sitting on your couch. But if you’re going to do 20 minutes, try to get your heart rate up, get the intensity up,” she suggests.

You can always increase your speed, incline or both to make a more challenging workout. Use that 20 minutes to work hard, and you may be able to burn as many calories as you would in 30 or even 45 minutes, she notes.

Roe recommends enlisting the help of a fitness trainer who has experience with weight loss and asking about their own fitness or weight loss experiences. Trainers who have successfully managed their own weight may be the best because they can relate to your journey and help you create a plan and schedule to reach your goals, he adds.

As mentioned, strength training workouts can help with weight loss too. As you build more strength and muscle, you’ll end up burning more calories 24/7, as muscle burns more calories than fat.

If you’re using a wearable fitness device that tracks calories burned, Freeman says it’s best not to get too hung up on the numbers just within your exercise period.

“Turn your body into a calorie-burning machine not just for the workout, but throughout the rest of the day,” he says. “Sustained weight loss is more attainable by increasing muscle mass (which boosts your metabolism).”

Roe also recommends setting realistic goals and finding someone who can keep you accountable, such as a trainer, support group or team.

Lastly, don’t let a lack of progress get you down.

“Weight loss is a journey and doesn’t happen overnight. It’s important to be patient when losing weight and not become discouraged,” Brown says.

And consistency is key – factor in time to work out each day, just like you do for meal planning.

“Essentially, make it a non-negotiable part of your life,” she advises.