Is Fasting the Best Way to Get Shredded?

There's almost no point in getting big if your large-and-in-charge muscles aren't visible because they're hidden underneath a glacier-thick layer of body fat. So if you're serious about your bodybuilding goals and you want to create your manliest possible physique, you're going to have to do some shredding.

Obviously, nobody likes the shredding phase. It's only the truly dedicated gym-goer who can tolerate counting calories, eating a bland, flavorless "clean" diet, focusing more on cardio, and lifting weights so small that it looks like they got lost on their way to a silver sneakers class. But once you're so defined and vascular that you want to kiss your own pythons every time you look in a mirror, all of that hard work suddenly feels worth it.

When it comes to shredding, though, fitness experts all over the world are torn as to how exactly you should go about doing it. Some seem to think that the science points to fasted workouts burning more fat and getting you shredded faster. Others claim that that's the worst idea ever, and that you'll be cannibalizing your gains in the name of trying to burn more fat more quickly. Below, we'll weigh in on both sides of this argument. And then we'll tell you exactly what you need to do for maximum shreddedness.

The Evidence for Fasted Workouts

Fitness science is constantly evolving. Take, for example, the myth about fat making you fat. Thirty years ago, this was accepted as Bible truth; today, however, we know better. We know that Wonder Bread and potato chips are your waistline's worst enemy, not the full fat sour cream on your breakfast burrito.

So what happens to your body when you work out in a fasted state? Well, for starters, working out while fasted jacks up your body's natural insulin sensitivity levels. Insulin is the hormone that helps control how much blood sugar you have circulating in your system at any given time. It's the key to unlocking your muscles so that you can shove as much protein and sugar (for energy and muscle repair, respectively) into them as you possibly can. The more sensitive you are to insulin, the less insulin it takes to do the job. Its also means that your body is more efficient at the task, which helps you get a leaner physique that much faster. Furthermore, it's great for endurance athletes who want to run a faster marathon and still have energy after to go about the rest of your day.

Another great thing about fasted exercise is the way it sends your growth hormone levels skyrocketing. And this effect stacks the longer you are fasting before you hit the gym. If you're the kind of beast who can fast for at least 24 hours and then power through a tough workout, you'll boost your growth hormone levels by somewhere around 2,000%. Women are similar - a 24-hour fast before workout can boost growth hormone by 1,300%.

As you can see, multiple studies across the spectrum of fitness science show that there's a pretty strong benefit to fasted exercise. It'll increase your athletic endurance, it'll help your metabolism use energy more efficiently, and it'll jack up your human growth hormone levels to help keep your body from cannibalizing muscle tissue when you're counting calories. So why would anybody not want to squeeze in a fasted workout here and there, especially when they're trying to get shredded?

Haters Gonna Hate (and Chug a Lot of Protein)

Most old school fitness experts, however, wouldn't dare set foot in the gym without a massive protein shake in hand. To their credit, just like the old fear of dietary fat, all of the science at the time told them that they were right. In the essence of fairness, below are the main reasons behind sticking to fed workouts, even when you're trying to burn fat:

• Safety is key. If you're new to the fitness game, if you take fasting to the extreme and push your body beyond its limits, or if you have a medical complication that would make a fasted workout dangerous, then it's best to play it safe and make sure you feel up properly before you exercise.
• Losing muscle tissue. When your body needs fuel, such as during an extended fast, there are some studies that suggests fasted exercise does break down more muscle tissue up to 195 minutes after your workout. Unfortunately, there aren't any studies that look into what happens during a longer recovery time - say, 2 or 3 days - after fasted exercise. With all the extra testosterone and growth hormone produced during a fast and after a fasted workout, we can't help but wonder if this muscle cannibalization is reduced during an extended recovery period.
• "Calories in vs. calories out". These people are indifferent when it comes to fasted versus fed workouts. They're mainly focused on the overall calorie deficit. But here's the thing: If your body has to choose between burning a fat cell for energy or using the sugar from your protein shake that's floating around in your bloodstream, it's going to go for the latter. And the former is still going to be stuck to your waistline, preventing you from seeing those six pack abs in the mirror.

The Best Way to Meet Your Goals: Find a Balance

So there you have it. Fasted cardio is great for athletic endurance and burning more fat more efficiently and more quickly. But fed workouts give you more energy to work harder for longer and give your body what it needs to build bigger muscles at neck-breaking speed. If you really want to get super jacked, you're going to have to balance fasted exercise with fed workouts for best results. And to get even better results on top of that, you're going to need some help. For our top picks, click here.