Should I do fasted cardio?

Pre-race breakfast

What happens if you run or exercise on an empty stomach?  What are the potential benefits?  Is there a downside?  There has been a lot of talk about fasted cardio and becoming “fat adapted”.  Personally, I find it hard to run on an empty stomach, but I have been curious about the overall benefits.  Could it lead to better athletic performance?

Fasted cardio is when you exercise, usually first thing in the morning, on an empty stomach in a fasted state.  If your glycogen stores are depleted, your body has to use a different source to fuel your workout….fat.

From what I’ve read, the purpose of doing cardio in a fasted state is to train your body to use it’s fat stores for fuel.  Basically, burning more fat for fuel versus burning the carbohydrates from the food we just ate.

The primary reason I found this interesting is that burning fat for fuel would come in handy while running long distances.  I’ve only run four marathons, but I’ve found it hard to find the perfect fueling strategy.   Could I avoid “hitting the wall” during a race by training my body to use fat for fuel?

When trying to train your body to become fat-adapted, you must do some “glycogen-depleted” workouts.  (Glycogen is a stored form of fuel for the body)  This means to do an early morning run with no food before or during.

While fasted runs can help the body adapt to effectively burn more fat for fuel, it probably won’t improve your endurance or aerobic conditioning.  According to Lauren Antonucci, RD, you can train your body to burn more fat than carbohydrates, but for most people you won’t see any long term athletic benefits.

Here are some findings in an article from Medicine & Science in Sports & Exercise:

“depletion of carbohydrate stores is associated with fatigue in the form of reduced work rates, impaired skill and concentration, and an increased perception of effort”

“carbohydrates provide a key fuel for the brain and central nervous system”

“there is significant evidence that the performance of prolonged sustained or intermittent high-intensity exercise is enhanced by strategies that maintain high carbohydrate availability

Another reason that fasted cardio might not be the best choice, as stated by health and fitness expert Pete McCall, is that “it could cause the body to burn protein for fuel, which would reduce the amount to be used to help build and repair muscle tissue.  If carbs are not available for energy, the body can convert proteins for fuel, which leaves fewer proteins available to re-build muscle post exercise.”  

I have also come to find that individuals who are fat adapted still need to ingest some form of carbohydrate during endurance races.  If this is the case, what is the point really?

I guess in the end it all depends on your goals.  If you are looking to lose weight, then this strategy may work for you.  According to Women’s Health magazine, some studies found that exercising while “fasted” can burn up to 20% more fat than if you ate before exercise.  (With that said, I believe weight loss comes down to overall lifestyle changes that are sustainable and not trying to “force” your body into burning fat).

Fasted Cardio. Should I try it? Is it right for me? Click To Tweet

Some people prefer to exercise on an empty stomach or just don’t have time to eat before an early morning run.  If this is the case, it’s important to pay attention to how you feel, as far as energy levels, nausea, or feeling light headed.  You don’t want to struggle during your runs or workouts.

Personally, I like to eat something before running.  After discovering that there is most likely no potential benefits in athletic performance, I will continue to do so.  I feel that even just a small amount of food gives me more energy and makes my run more efficient and enjoyable!

As for fueling for my next marathon, I will be relying on carbohydrates.  Through trial and error, I will find what works best.

Do you exercise on an empty stomach?

Have you become a fat adapted athlete?  I would love to know if anyone has had positive results using this strategy!

How to set SMART goals

Goal= “the object of a person’s ambition or effort; an aim or desired result“.  Goals are an important part of life.  They can give you a boost in motivation and help with staying organized.

We can have short term goals, such as completing three workouts per week and long term goals, like weight loss.  Goals help us focus our attention on what we want to achieve and keep us on track.  Small steps and short term goals keep us on the right path to accomplish our long term goals.  Goals help us determine what’s important to us and keeps us focused.

We can “get to work” on our most challenging struggles with goal-setting.  Whether it be health goals, fitness goals, or work related goals, making a specific plan is key.  We want to be able to focus our time and energy on what we want to accomplish and also be able to track our progress along the way.  An effective way to prepare for success is by setting SMART goals.

SMART stands for specific, measurable, attainable, relevant, and time-bound.  SMART goals will help “pave the way” for your success!

SPECIFIC:  What do you hope to achieve?  Your goals should be clearly defined.  You should state exactly what you want to accomplish.

MEASURABLE:  How will you know if you achieve said goal?  Being able to see the progress you’ve made will help your motivation to continue.

ATTAINABLE:  Is your goal really one that you are actually able to achieve with a reasonable amount of work?  The goals you set should be sensible and practical.

RELEVANT:  When you reach your goal, how will it make you feel?  Choose a goal that is important and worthwhile.  You want your goal to be appropriate to your needs, interests, and skills.

TIME-BOUND:  When do you want to accomplish your goal?  If you specify a particular date by which you want to reach your goal, it will keep you on track.  Consistently keep an eye on your progress to make sure you are moving forward toward your goal.

When setting goals, make sure they are SMART! Click To Tweet

Having SMART goals will certainly increase your chances of success.  This will help change a non-specific plan into a clearly defined plan.  Defining your goals this way will motivate you and help you remain focused.

I think it helps to actually write it down.  Seeing your goals spelled out on paper makes it “real”.  Taking the time to sit down, make a plan, and knowing the steps that you need to take gives you accountability.  Increase your chance for success and make your goals SMART!

Do you set specific goals?

Trans Fats

Trans fats.  What are they?  Where are they found?  Will they affect my health?  These are all great questions and very important questions to get answered.

Trans fat occurs naturally in some animal products.  The naturally occurring trans fats are produced in the gut of some animals, so food made from them may contain small amounts of trans fats.  Artificial trans fats(trans fatty acids) are the ones we need to be aware of.  These are made by a process called “hydrogenation” where hydrogen is added to liquid vegetable oils to make them more solid.  Partially hydrogenated oils (PHO’s) are the primary source of trans fats in our diets.

Partially hydrogenated oils have been used since the 1950’s mostly to increase the shelf life of foods.  These fats are also inexpensive and easy to use.  Many restaurants and fast food places use trans fats to deep fry foods because these oils can be used over and over in commercial fryers.  It wasn’t until the 1990’s that research began to find negative health effects from consuming trans fat.

Eating trans fat raises your LDL (bad) cholesterol levels, while lowering your HDL (good) cholesterol levels.  An elevated LDL increases your risk for developing heart disease and stroke. Consuming these fats is also linked with increasing the risk of type 2 diabetes.

Researchers at the Harvard School of Public Health estimate that trans fat causes 72,000 to 228,000 heart attacks, including about 50,000 fatal ones, per year!” (Center for Science of the Public Interest)

Nutrition Facts Label

In January of 2006, the Food and Drug Administration (FDA) made it a requirement to label the amounts of trans fat in foods, including dietary supplements.  Apparently, the average American adult has been consuming 5.6 grams of trans fat a day!  Having the amounts visible on a nutrition label is great.  We should definitely be made aware of any trans fat in our food.  Knowing this lets us make healthier choices to help us lower our intake of these harmful fats and in the end reduce our risk of heart disease or any other negative health effects.

Some of the places that trans fat can be found:

  • baked goods (cookies, cakes, pies, crackers)
  • ready to use frostings
  • snack foods (such as potato chips and microwave popcorn)
  • fried foods typically found in fast food restaurants
  • refrigerated dough products (biscuits, cinnamon rolls, frozen pizza)
  • vegetable shortening
  • stick margarine
  • coffee creamer

In 2013, the FDA made a “preliminary” determination that partially hydrogenated oils could no longer be generally recognized as safe (GRAS).  After a “thorough review of scientific evidence,” this determination was finalized in June of 2015.  So today, these oils are no longer GRAS (safe).

Food companies have until June 18, 2018 to remove all PHO’s from their food.  After this date, these fats cannot be added to any human food unless approved by the FDA.  According to the FDA, many companies have already been working on removing these trans fats.

The best way to make sure you’re not consuming these harmful fats is to check ingredient labels.  If it has partially hydrogenated oil listed, put it down!  A food can have 0.5 grams of trans fat or less and it is allowed to be labeled as containing zero grams.  This doesn’t make sense, but that’s the way it is.

For example, lets say you’re eating some crackers.  The label states that it has 0 trans fat, but it actually has .5 grams per serving.  You eat 3 servings and you’re getting 1.5 grams of trans fats!  That’s why it’s important to check those ingredient lists!

What exactly are TRANS FATS? Are they harmful to my health? Click To Tweet

Nutrition plays a significant role in our health and the prevention of chronic health problems.  Fortunately, by this time next year, we won’t have to worry about trans fats being in our food.  But, for the time being, we have to check those ingredient labels for the hidden partially hydrogenated oils to ensure we are making the best choices for our health and well being!

Do you try to avoid trans fat in your diet?


*References: and American Heart Association*