What Is Fasted Cardio? Is This Fitness Trend Safe?

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Fasted cardio consists of not eating for hours before a workout, which can burn more fat. What Is Fasted Cardio? Is This Fitness Trend Safe? www.runnerclick.com

We’ve all heard of fasting and the wonders it can do for weight loss when we aren’t eating past a specific time. But what would happen if we applied the same mentality to our workouts? Enter in fasted cardio, a new workout trend that is said to help burn more fat.

Fasted cardio just might be the big thing in the fitness space. However, many might wonder if it’s the type of approach to workouts that is right for them.

It could be a great way for those who are dedicated to eating better and exercising and have hit a weight loss plateau. Fasted cardio has the potential to be that kick starter the body needs to get over that hump.

But others might find that fasting before an intense workout isn’t the best for their needs. Those training for a big race might need the extra calories beforehand to power through the endurance exercise at hand.

Like anything in the health and fitness space, there are pros and cons to fasted cardio.

Fasted cardio aids in weight loss.
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The Same Logic As Intermittent Fasting

When looking to lose weight, many swear intermittent fasting is the way to go.

This is a popular diet method consist of refraining from eating for short periods. This includes not eating after 8 p.m. and fasting for 16-hours.

There are a few methods including those who skip breakfast and only eat for eight hours. Others just fast for 24-hours once or twice a week. And others restrict calories drastically for two days but eat normally on the other days.

This is done to regulate hormones, specifically lower insulin levels which aid in fat burning. It also helps people eat fewer calories in general. This both leads to weight loss.

What Is Fasted Cardio?

Fasted cardio follows a similar method.

It includes not eating—this includes a pre-workout snack—eight to 12-hours before a cardio workout.

As a result, there is no glycogen to break down and insulin levels are low.

The idea is that the body then is burning fat, not whatever fuel was consumed before the aerobic activity.

Since that pre-workout meal like breakfast or a snack probably includes some kind of carbohydrates, which is the body’s preferred source of fuel, it has no choice but to burn fat.

How To Do It Right

Fasted cardio could be great for fat burning.
Photo by Nate Johnston on Unsplash

Those considering trying fasted cardio need to do it properly to see results. This means not consuming anything before the workout.

However, water is absolutely allowed. Even more, it’s encouraged. Dehydrating the body only leads to negative health effects, especially since we are about to work up a sweat.

Feel free to drink all the water wanted.

It’s also best to practice fasted cardio first thing in the morning. Fasting all day to get to a nighttime cardio session without eating anything isn’t the best idea. Expect to crash.

Instead, stop eating at a specific time before bed. After a good night’s sleep, upon waking up, get the cardio workout done. This generally means eight to 12-hours passed.

Just make sure to eat breakfast afterward not before.

This method is preferred by many. Runners might opt to not eat before going for an early morning run. They just probably just know they were practicing fasted cardio.

Those used to eating before a workout sometimes find fasted cardio a challenge. There is a good chance of feeling a lack of energy those first few workouts before getting used to it.

Fasted cardio isn’t for those about to log some serious miles or go for a hardcore workout. It’s more for those specifically looking to increase fat burn when getting in a short run or cycling class.

But Does It Even Work? 

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Fasted cardio sounds like it works in theory. But does it really work? And more importantly, is it even safe?

The good news is that it does show some promise for increased fat burning. According to one study, participants who ran after fasting burned 20 percent more fat than others who ate that same morning. 

Another study published in the Journal of Applied Physiology found that fasted cardio athletes saw an improved to their endurance compared to those who ate beforehand then worked out at the same intensity. 

Experts believe that fasted cardio works best during workouts that are longer than 30-minutes, and specifically for endurance athletes like runners. 

Fasted cardio is considered safe for these types of athletes as well as other endurance athletes like those who compete in triathlons because their bodies are already conditioned for intense exercises as well as used to rapid calorie and fat burn.

It’s not best for those who are new to exercise regimens who might need that extra fuel to help them get through a workout. 

Plus no one wants to feel dizzy or too exhausted to even complete a workout. 

Restricting calories and exercising intensely might be enough on its own. Pushing it to then workout on an empty stomach might be too much for some.

Keep in mind that another study found that fasted cardio results in too small of a change to body mass to even be worth it. 

And from a biology standpoint, fasted cardio might just help with the release of fatty acids from fat cells. There is a chance that fat isn’t actually being broken down.

Another risk is that the body breaks down muscle tissue instead of fat.

So Should We Try It?

Those looking to jumpstart their weight loss might want to give it a try. Just make sure that there is exercise experience. If feeling lightheaded or nauseous during the workout, fasted cardio isn’t for you.

Fasted cardio isn’t meant for those training for a marathon or a triathlon. Also, don’t go to that CrossFit workout or HIIT class when still fasting. It’s best to keep the aerobic exercise to something more light.

The bottom line is many people practice fasted cardio and don’t even know it.

Some prefer to work out on an empty stomach whereas some don’t. It ultimately comes down to preference.