What is Intermittent Fasting? Fasted Cardio?

Intermittent fasting is a pretty big buzzword in the fitness industry these days. So big, that I think this idea, and others that stem from it, are made to sound much more complicated than necessary.

In this article, I hope to define what intermittent fasting is and provide some scenarios that make it simple to understand.

Intermittent Fasting

In a nutshell, intermittent fasting is saving calories.

A fast is willingly withholding yourself from calories. Intermittent fasting is simply cycling between periods of fasting and eating.

So, within a day you can have an extended period of time where you withhold yourself from food/calories. If you’re operating within a flexible dieting plan, you can withhold those calories in order to have a larger meal later in the day, or fit in a specific type of food that you really love that may be higher in calories.

For example, I recently had a day of intermittent fasting where I ate a small breakfast early in the morning that held me over for seven hours until I had another, much larger meal. On this day, I consumed 310 calories (protein bar and scoop of protein) for breakfast around 8:30 a.m. I didn’t eat again until 4 p.m. In between, I did some work, went to the gym, stopped at the grocery store, and ran a few other errands.

That probably sounds like a normal day for many people, right? Get up, eat, take on the day, and have another meal when you’re done.

If you’ve done that, you’ve done intermittent fasting.

I also used to do this in the past, as early as high school, but there wasn’t this catchy buzzword for it back then. I never ate breakfast when I was a kid, but I ate huge lunches and dinners. I was performing intermittent fasting from my last meal of the day through my sleep cycle and morning activities.

It’s really a pretty simple idea. You can even consider when you’re sleeping to be intermittent fasting. When you wake up, you eat food for breakfast for the first time in 7-8 hours.

Breakfast.

Break. Fast.

Now, I personally see the majority of the positive impact from intermittent fasting coming from the ability to have a flexible diet. That’s how it serves me best and with the most value. However, there are some other potential benefits.

Fasted Cardio

Some people use intermittent fasting to supplement their training and specific goals. Fasted cardio is a great example.

The idea behind fasted cardio is that it will help with fat loss goals, because burning calories on an empty stomach will force your body to burn more fat than a traditional cardio session.

In simple terms, your body searches for carbohydrates first to use as fuel for your training.  The concept here is if you’re fasted, those carbohydrate levels should be quite low, forcing your body to then use fat as an alternate source of energy.

Now, a potential downside is your body could also search for muscle (proteins, amino acids) for fuel. Depending on your goals, maybe this isn’t ideal, and you need to supplement your diet to prevent against muscle loss. I’ll document this in another post.

But overall, that’s the gist of the thinking behind fasted cardio.

Now that’s a great idea, in theory, but there’s not a lot of science to back it up. In fact, most of the studies seem to suggest one of two things:

  1. There’s no discernible difference between fasted cardio and cardio on a full stomach, or…
  2. Doing cardio with food in your system is actually more effective for fat loss, as the post-workout fat burning process has a greater impact if your body has energy to utilize during your workout.

Depending on your training goals, one form may be better than the other. I was steered in the direction of a lot of these studies thanks to Scott Herman’s recent video on fasted cardio. He includes links to relevant studies and papers in the description.

Conclusion

I hope this gave you the basic information needed to understand intermittent fasting. It’s not rocket science. It’s simply managing your calories in a specific type of way.

Intermittent fasting doesn’t have to happen every day. It can be as needed or as preferred. You can do it one day a week or seven. It’s really just yet another example of how a flexible dieting plan can be executed.

If you have any further questions about intermittent fasting or fasted cardio, feel free to ask away in the comments section below. You can also reach me on Twitter @Holistic_Fit or shoot me an e-mail at holisticfitnesschris@gmail.com.