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If you're something like us, your IG-Feed has a high volume of ~ fitspirational ~ belfies, smoothie and (lately ) proud body hair. But there is another thing that people like to talk about (no,
On their social platforms: fast cardio training.
What is fasted cardio, right?
Basically, fasted cardio involves increasing your heart rate Without having to forego a pre-workout meal or snack beforehand, cardio fanatics claim that the practice maximizes your fat burning potential, but of course, wondering whether exercising on an empty stomach is a good (and safe!) idea or just a trend that sounds legit. * Sigh *. [1
First things first: how long do you have to give up food to call your training "almost"?  Normally eight to twelve hours, says sports doctor Natasha Trentacosta MD of the Cedars-Sinai Kerlan-Jobe Institute in Los Angeles, but for some people it's only three to six hours, as the case may be How fast your digestive system works and how much you ate during your last meal. "Once your body stops processing and breaking down food, your insulin levels are low and there's no fuel (glycogen) in your blood," says Dr. Trentacosta. As a result, your body needs to turn to another source of energy – usually fat – to drive you through training.
Usually cardio training happens in the morning (after a nightly fast). However, a fasting state can also be reached later in the day (such as when you are missing fasting or lunch), says sports physician Kacie Vavrek, MS, RD, CSSD of Ohio State University's Wexner Medical Center.
Bodybuilders have been using fattened cardio for years as a fat loss technique, and recently it has also been used by fitness students. However, you may have already done hearty cardio training without realizing it. Every time you go directly to an early morning workout without eating, do a quick workout. (See also: Early waking up for a morning workout, according to women who do it at 4am.)
The benefits of fasted cardio
When your primary goal is to lower your body fat percentage and walking effort Training is cardiovascular with low to moderate intensity, with fast cardiovascular there may be some benefits. "Research helps you burn more fat in the fastest state than if your body does not have any nutrients in the circulation that it can use as an energy source," Dr. Trentacosta. For example, a small study found that people running on a treadmill at the fastest rate burned 20 percent more fat than those who had taken breakfast.
Why? If you do not have enough energy from your diet, your body needs to look elsewhere, Dr. Trentacosta.
"The accelerated heart can cause the body to burn stubborn fat if someone trains regularly," agrees the chiropractic and certified strength trainer Allen Conrad, BS, DC, CSCS. "Read: Newbies should not try This is because people who have been training for a while know their limits and are more in touch with their bodies, he explains.
When you run empty, you will suddenly feel lazy to burn Fat is more efficient for fuel Conrad says that this can be beneficial if you exercise for more than 30 minutes at once or several times a week (such as endurance runners or triathlon drivers.) Indeed, research published in the Journal of Applied Physiology were published, namely comparisons between fasting and feeding over a six-week period, wherein it was found that in training with the same intensity, those who have consistently trained in a state of fasting
Perhaps one of the main reasons why people on an empty stomach are exercising is the reason that skipping a meal or snack before exercising a few means more valuable zzz values. The standard recommendation is to wait at least 30 minutes after eating to exercise – and that's when you only have one banana or slice of nut butter (and not a three-egg omelette with bacon). Having a full breakfast before heading to the gym in the morning is a pretty obvious recipe for GI suffering. The simple solution: waiting for food until after your training. (See also: What to Eat Before Exercising and When to Eat It)
The Disadvantages of Fasted Cardio
Here's the thing: While your body may possibly turn to the fat stores in your fat tissue Energy, it does not make any difference where the energy comes from. Trentacosta. This means that your body can break down your muscle tissue as fuel. Ugh.
Vavrek agrees, adding that your body uses the protein your muscle tissue contains as fuel instead of fat from your fat tissue. In fact, one study found that one hour of constant cardio in the fasted state led to twice as much protein breakdown in the muscles compared to non-fasting cardio. The researchers concluded that performing cardiovascular exercises during fasting is not a good choice for people who want to build or maintain muscle mass. (Related: Everything You Need to Know About Burning Fat And Building Muscle)
Whether your body burns fat or breaks down muscles ultimately depends on the type of exercise you do, says Jim White, RDN, a physical therapist at ACSM and Owner of Jim White Fitness and Nutrition Studios. "The idea is to stay between 50 and 60 percent of the target heart rate, which you can do during a walk, a slow run, an elliptical trip, or a yoga class." The lighter the workout, the more likely your body will use fat.
On the other hand, workouts with a higher heart rate and intensity require more carbs for fast energy. Without them, you will probably feel tired, weak, sore and even sick or dizzy. (That's the reason why keto dieticians may need to rethink their exercise routines while participating in a high-fat plan.)
Translation: If you're in the fastest state, you should not use HIIT, Boot Camp or Performing CrossFit classes says White – and definitely not training. If you lift weights while fasting, you do not have the strength to lift as well as you can. At best, you will not maximize the benefits of your workout. In the worst case, you could be hurt, says White.
Regardless of the intensity or type of exercise, Vavrek warns of rapid cardio. "Exercising in the fastest condition is simply not the best option for losing weight." The reason: if you are not energized, the intensity that you can bring to a workout is limited, and it has been shown that you burn more fat and calories through intensive training in the 24 hours after HIIT training can run as a constant pace. This has a lot to do with the fact that the total number of calories burned during HIIT is so high that your body will burn both carbs and fat during these fast, intense workouts. An older study also found that pre-exercise carbohydrate intake increased post-exercise afterburn more than fasting. (Related: The Science Behind the Afterburning Effect)
So is it worth the accelerated cardio?
Maybe. The evidence is pretty mixed, so it's ultimately down to your personal preferences and goals.
"There are absolutely people who love it, in part because it's something new and partly because it just works their body," says White. If you work out in the morning and do not feel like sweating, it might be worth trying.
If you decide to fast, be sure to eat after exercise, he says. His goal is a PB & J smoothie, but there are tons of post-workout formulas that contain the right combination of carbs and protein. Fair Warning: You may be hungrier than usual.
That being said, Fastenkardio is probably not the best option for most. "Many people get tired or hit a wall during exercise without fuel, and some even get dizzy," says Dr. Trentacosta. (That's why Conrad stresses the importance of talking to a health care provider before cutting out the pre-workout fuel.)
If you want to work out while you're hungry, then there are many other, more effective ways of getting fat to burn.