Intermittent Fasting: Use Fat As Source Energy
How To Burn Fat And Build Lean Muscle Mass At The Same Time
You may have heard of something called intermittent fasting. People have been raving about this new fat loss method, so what is it, how does it work, and is there any truth behind it? Is it dangerous?
Intermittent fasting is a way of restricting calories by not eating for set periods of time. The goal of fasting is to put your body in a ‘fasted state’ which is a natural state your body moves into after several hours of not eating.
With this article Intermittent Fasting, you will understand everything about the fasted state.
Your body actually has a natural metabolic cycle to burn fuel, so intermittent fasting is actually less of a diet and more of a pattern of eating that keeps your metabolism working at it’s best. In the most simplistic explanation, it cycles between the ‘fed’ and the ‘fasted’ state.
The ‘fed’ state occurs right after you eat. Over the next couple hours your body uses the fuel that you just ate, but the majority is stored away. The insulin hormone is responsible for the fuel storage, and it’s highest right after you’ve eaten and your blood sugar is high. It’s job is to lower blood glucose to a normal level, which is why it promotes storage of the glucose as glycogen or fat. There is only a limited amount of carbohydrate fuel that can be stored as glycogen (Storage form of glucose), so the majority is converted to fat.
The ‘fasted’ state occurs several hours after not eating, when you have used up quite a bit of your short term energy storage (glycogen/glucose). Since the blood glucose is low, insulin is low, but another hormone, glucagon, gets higher. Glucagon promotes the use of fat as energy for the body, so that the glucose can be saved to keep the blood sugar balanced and be used mainly as fuel for the brain, since the brain doesn’t like to use fats for energy. Another hormone that increases in the fasted state is GH (Growth Hormone), which is exactly what it sounds like, and promotes building and growth of body tissues, including your muscles.
So, since the body is primed for muscle growth, does that mean it’s good for fitness?
Yes... and no.
Yes, because if you exercise in a fasted state, you will burn more fat and your body is primed for muscle building, but if you plan to continue fasting afterwards without fueling up, you may not be making the best progress overall.
Really, it just depends on your goals, and how you schedule fasting around working out to make sure you’re not burning yourself out completely. Let’s learn a bit more about intermittent fasting methods before we talk about that…
There are plenty of benefits when your body is in the fasted state for a longer period of time, including:
- Reduced blood sugar (glucose) and insulin levels.
- Preserves muscle tissue and promoted lean body mass.
- Lowers inflammation and blood pressure.
- Makes you live longer.
There are a lot of mental barriers to this method of fueling or feeding your body, mainly because it is constantly shoved down our throats that we need to keep eating all the time and we need to have a specific amount of meals per day to be healthy. In reality, we don’t need to eat every few hours, and it is can actually be beneficial to let your body enter into the fasted state every once in a while!
We used to be hunters and gatherers, and half of the time we went for hours and hours without food. In our current society food is almost always available to us and promoted constantly in many different ways. It’s easy to forget that our bodies can adapt to a lot of things.
Though some intermittent fasting plans can include complex meal plans and scheduling, others are very flexible and easy to incorporate into everyday life. Since there are so many ways to fast, we’re going to simplify it into two types:
The first type requires you to take a longer fast, usually a 24 hour period. Normally this is only done once or twice per week, but some people will do alternate day fasting. As an example, you could do dinner at 6pm one day, then fast until the next day at 6pm, when you can start eating normally again for the next 24 hours, and then start the cycle over again.
The second type requires you to fast every day, or several times a week for a shorter period of time. This is usually closer to a 16 hour fast, which can be done overnight, starting after dinner time or in the evening, and skipping breakfast the next day, starting to eat normally again at lunchtime.
This period where you are allowed to eat as normal (start consuming meals and snacks as usual) is also called an eating window. In the previous example the eating window is from noon to 8pm, and then you fast overnight until the next eating period at noon the next day.
There are a few ways to modify these two plans to fit your needs and make fasting work for you:
- Some plans allow for no-calorie or low calorie drinks like coffee and tea during the fast.
- Others allow you to eat during the fast, which can make it much easier for some people to accomplish, but only 20% of your normal calorie intake is allowed.
- Starting with a smaller fasting time and then building up to longer ones can get you used to the idea that it’s okay not to eat sometimes.
- Only doing a fast every once in a while (Some people do once a month) can help you reap the benefits, without committing to the full lifestyle.
It may seem weird, ‘skipping’ meals, but you’re not supposed to actually cut them out, you are simply moving all of your caloric intake into that specific feeding window. We are just used to consuming food at specific times in groups of ‘meals’ or ‘snacks’
However, this is not an excuse to binge eat or overeat because you haven’t eaten in a long period of time. Your food choices should also be mainly healthy, to make sure that you are still getting the essential macronutrients, vitamins and minerals in your diet, even though you are fasting for set periods of time.
You should also talk to your doctor if you have any medical conditions that could be affected in a negative way by fasting.Fasting also may not be suitable for those who have a heavily active lifestyle, simply because more calories are needed for more energy for activities, and fasting is a form of calorie restriction. Though for some it can simply be arranged into a specific schedule that works for that person, or done less often.
We gave you Intermitent fasting: fasting seems complicated, but it can actually be very simple.
Let’s review what we learned:
- The body has natural states for storing fuel and using it called the fed and fasted states
- Fasting and the fasting state has many benefits for the body, including fat loss and lean muscle gain.
- There are lots of different methods and ways to make fasting a part of your life and schedule.
- The fasting state is good for exercise, but fasting for long periods before and after exercise is not.
- This eating pattern may not be good for heavily active people, those who tend to binge eat, and those with medical conditions.
Make your body work for you!
van Praag, H., Fleshner, M., Schwartz, M. W., & Mattson, M. P. (2014). Exercise, energy intake, glucose homeostasis, and the brain. The Journal of Neuroscience, 34(46), 15139-15149.