The Best HIIT Workouts to Build Muscle and Reduce Fat

We find you the best (and fastest) HIIT workouts to build muscle and reduce fat

For some exercise addicts, the perfect workout consists of heavyweights, iron noise, and long breaks to recover. But not everyone goes to the gym with muscle growth and strength building as the end goal. If your goals are to improve your fitness level, burn some fat, and sweat, you’ll need to pick up the pace past those 90-second rest periods and add some cardiovascular elements to your workout.

One of the best, most popular ways to introduce some cardio without entering the boring steady-state zone of treadmills and stationary bikes is by implementing high-intensity interval training protocols. Even if that long, word salad phrase isn’t familiar to you, you probably know the more common acronym from countless boutique gym concepts and online workouts: HIIT.

The protocol is popular for a reason. HIIT allows trainers to pack a ton of work into a small amount of time, making workouts effective, quick, and more engaging than a long slog on a cardio machine. HIIT workouts burn fat and push your heart rate, and allow you to keep the weights in your training. Because of the second word in the acronym, ‘intensity,’ exercisers are likely to feel super accomplished after surviving a particularly challenging session.

But in some contexts, particularly in the boutique gym space, HIIT is overused and misapplied—and that intensity is the only aspect of the protocol that carries over into practice. As HIIT has become a fitness buzzword, the exact specifications of the protocol have become hazy to the general public, so any workout that gets people up and moving is tagged with the label. That’s not quite right. There are specifications that matter.

For HIIT to be utilized correctly, your intensity has to be high–but you need to know how to apply the protocol. That’s what you’re going to learn here, and you’ll also walk away with a handful of HIIT workouts for every situation, too.

HIIT 101

HIIT stands for high-intensity interval training, which refers to the short bursts of intense exercise alternated with low-intensity recovery periods that make up the protocol. HIIT is quick and anything but boring, as its exacting work-to-rest ratios, make it arguably the most time-efficient way to exercise and burn calories. You can use the HIIT protocol to build your entire workout or apply it to just a few sets to create super-charged finishers.

However, you do it, what makes HIIT work is the intensity. You’re going hard, typically as hard as you can, for a short period of time, then resting for a length of time that’ll let you recover to go hard once again. The Work-to-rest ratio is frequently brought in when discussing HIIT, and there are several accepted ratios you should consider.

To improve aerobic fitness: intervals would typically involve a work to rest ratio or 1:1 or 1:2 (i.e. work for 30 seconds, rest for 30 seconds).

To train anaerobically (sport-specific training for power and explosiveness): rest intervals are often longer to allow for a more maximal effort, often at least a 1:5 ratio (i.e. work for 15 seconds, rest for 75 seconds).

The Key to HIIT

The key to making HIIT work: The intensity. You can’t coast through your work periods when doing HIIT. The protocol is designed to give you chances to go hard, so you need to take advantage of those changes.

That means working hard, but it doesn’t mean going completely 100 percent with your intensity. If you’re completely new to exercise, don’t go truly all out all at once. Instead of 15 to 30-second intervals executed at near-100 percent intensity, intervals of one to three minutes at closer to 80 percent of maximum effort, followed by up to five minutes of lower intensity exercise, have also been shown effective for weight loss in sedentary populations.

In group fitness settings (and among far too many trainers) HIIT and “interval training” are often used interchangeably. Make no mistake: True HIIT requires you to be explosive and intense during your work period. Basic interval training, however, minus the high-intensity aspect, is what you see most on the group fitness scene: Work periods here are typically larger than rest periods.

The Primary Benefits of HIIT

Fat Loss

One review looked at 13 different studies on 424 overweight and obese adults. It found that both HIIT and traditional moderate-intensity exercise can reduce weight and waist circumference

Metabolic Rate Is Higher for Hours After

Some researchers have found that HIIT increases metabolism for hours after exercise even more than jogging and weight training. This is known as excess post-exercise oxygen consumption (EPOC, informally called afterburn), a measurably increased rate of oxygen intake following strenuous activity.

Overall Health

HIIT is not just a tool to use to lean out. It can improve your overall health, too. A summary of 50 different studies found that HIIT reduces blood sugar levels. Further research shows it can reduce resting heart rate and blood pressure in overweight and obese individuals.

Some Ways to HIIT

So, wait, you’re still technically on that dreaded treadmill, right? Not necessarily. Here are 14 HIIT workouts that can keep you off the treadmill (well, for the most part) and on a far more fun path to major fat-burn.