Exercising On An Empty Stomach: What You Need To Know

Mar 30, 2017 //

There are a lot of myths and rumors about whether or not it is better to exercise on an empty stomach. Some people are told to eat a big meal before they hit the gym, while others claim fasted cardio is the only way to burn fat, fast.

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So which is it? The answer depends on what workout benefits you are looking for.

Check out these facts about working out on an empty stomach and get informed.

You Are Likely To Burn More Fat

When you eat, your body converts calories into energy that is distributed to meet your body’s needs. The thought goes that if you eat and immediately hit the treadmill, your body will convert most of whatever you just ate into the energy need for your workout. Those calories will be burned in the process.

Also Read: How To Lose Fat (And Keep Your Muscle) With Fasted Cardio

The trouble is that your body probably already has a lot of the energy that you need to workout stored up as fat. If you work out on an empty stomach, your body is forced to draw on those stores of fat for energy instead, meaning you’ll burn more of the stuff that you are actually trying to get rid of.

You Might Feel Less Nauseous

Remember your grandma telling you not to get in the pool because you just ate? Or, remember that one time you ate a big meal and ran to burn it off, but ended feeling sick? There was a reason for all that.

Many people feel nauseous or get sick while exercising, and there are a few common reasons why:

  • Dehydration
  • Low blood sugar
  • Eating too much, too soon

Some of those causes sound contradictory, right? They’re not. Eating before working out can make you feel sick because you are forcing your body to do too much all at once (digesting acids, sugars, proteins, and more while all of your major systems and muscles are being stretched and forced to work otherwise — not good).

Not being hydrated, though, or having a healthy blood sugar level can also be a problem. The good news is, you don’t have to eat a ton to solve that. Just drink a glass of juice or detox water before you workout so that your body is hydrated and your blood sugar is at optimal levels.

Your Muscles May Grow Faster

Periods of fasting are actually known to help boost muscle growth rapidly. The key to working out on an empty stomach is to practice intermittent fasting. Practiced by many body builders, intermittent fasting is all about controlling when you eat the nutrients that you do need, and when to fast so that your body is forced to break down fat stores and grow your muscles.

That’s right — for muscles to build up, they have to break down first. Just like your body draws on fat stores when you workout with eating first, your body will eventually draw on stored amino acids if left hungry long enough. Amino acids are largely found in your muscles.

You May Burn Out More Quickly

Of course, with your body having to draw on its stores of energy, you use up more energy. As a result, working out on an empty stomach can cause you to burn out more quickly.

You know the feeling. You’re five miles into your jog and it feels like you’re going to collapse — and you just might! Your body can only draw on so many stores of energy healthily while continuing at a strenuous exercise pace.

So, if you are exercising then to build endurance, you will definitely need to eat something nutritious before your workout.

You Will Need To Eat Sooner After Exercising

To reap the most workout benefits possible when you do decide to exercise on an empty stomach, you will need to eat immediately after you finish working out. Your body needs to be hydrated and nourished to function properly and to rebuild the muscles that you have broken down.

Eating within 45 minutes of finishing your workout fits well within the “anabolic” window for maximum fitness. The anabolic window refers to the time after exercise in which re-growth is jump-started. Fueling your body with protein and essential nutrients during this time frame will give your body what it needs to replenish and come back stronger.