Intermittent Fasting Variants - Part 1
My three most popular IF protocols for competing clients
For Performance Sports, Burning Fat and Building Muscle
Written by: Joachim Bartoll
Classic Muscle Newsletter, May 2015 (issue #9)
In 2009 I published a short article about intermittent fasting and how to use your pre- and post-workout nutrition to your advantage. In 2013 I updated the article and published it through MM Sports and Body Science Magazine. The update included strategies how to include amino acid pulses throughout the day. In this article I will go through the three most popular fasting influenced protocols I use among my competing clients.
Intermittent Fasting at-a-glance
Intermittent Fasting or fasting for about 16 to 20 hours followed by 4 to 8 hours of feeding, is powerful strategy for shedding body fat and reducing your risk of chronic diseases like diabetes, heart disease, and cancer. It can also be used for building muscle mass while keeping body fat gain to a minimum.
Three major benefits from fasting includes increased insulin- and leptin sensitivity and mitochondrial energy efficiency; reduced oxidative stress and inflammation; and increased capacity to resist stress, disease and aging.
Fasting helps the body to become fat adapted (burning fat instead of sugar as its primary fuel), which dramatically reduce your cravings for sugar and your risk of chronic disease and especially cancer. Cancer cells cannot utilize fat for fuel, they need sugar to thrive.
A recent study published in Cell Stem Cell discovered that Intermittent Fasting causes your body to strengthen your immune system by getting rid of damaged white blood cells and replacing them with new ones, shifting stem cells from a dormant state to a state of self-renewal.
Another way Intermittent Fasting improves your immune system is by improving the beneficial bacteria in your gut. A more balanced and healthy gut bacteria will also help you sleep better and increase your energy, mental clarity and concentration.
The term intermittent fasting has become quite diluted in the last 5 years. Most trainers, nutrition experts and fitness bloggers have their own variation of Intermittent Fasting. In some cases people will tell you that they’re fasting and all they do is skipping breakfast or skipping dinner. That’s not Intermittent Fasting and it’s definitely not fasting. That’s simply “under eating” by removing one single meal.
My first contact with “Intermittent Fasting” was back in 1998 when I ran the Internet-magazine Ironmag L.L.C and we wrote about The Animal Diet (a.k.a. Animalbolics). The concept of Animalbolics was later copied by Ori Hofmekler and his Warrior Diet and a couple of years later other variants surfaced such as Dr. James Johnson’s The Alternate-Day Diet and Martin Berkhan’s Lean Gains – and in recent years we’ve seen Brad Pilon’s Eat Stop Eat and Fat Loss Forever by Dan Go and John Romaniello.
Defining Intermittent Fasting
Intermittent Fasting is not really a diet, but rather a dieting strategy that follows a scheduled pattern with a period of fasting followed by a shorter period of feeding. By fasting and then feasting on purpose, Intermittent Fasting means eating all your food during a specific window of the day, and choosing not to eat food during the rest – thereof the term “intermittent”.
Also keep in mind that the fasting protocol that might be best for you will depend on your amount of body fat, hormonal status, general health, and fitness goals. Are you a competitive- or elite athlete? Or is your goal to live a longer and healthier life? Each goal requires a different strategy and approach to eating. You cannot achieve a very muscular body and/or superior fitness and maximum longevity at the same time. I will not go into detail about all the health aspects in this article, but I will touch on the subject again in part 2 in some easy to understand examples.
Another important thing to keep in mind is that proper nutrition becomes even MORE important when fasting. You only have a few hours to eat each and every day, so addressing the foods you eat should be your first step. Fasting and then eat whatever you like during the feeding window could lead to disaster very quickly.
If you have a lot of weight to lose, or if you haven’t been on a diet in a long time and are used to eating a lot of carbohydrates, I recommend that you start your Intermittent Fasting with a low carb approach. The reason for this is to quickly improve your insulin sensitivity and make you fat adapted. This means that your body becomes more efficient at using fat for fuel. It also helps with any cravings you might have for sugar. And improved insulin sensitivity will help to steer all carbohydrates to your muscle cells instead of your fat cells once they’re introduced.
Simply minimize your carbohydrate sources like pasta, rice, bread and potatoes and exchange them for healthy fats like natural butter, raw organic milk and cream, eggs, avocado, coconut oil, olive oil and nuts. Aim at a protein intake of about 1.8 to 2.2 grams per kilogram of lean body weight (0.8 to 1 gram per lbs/lean bodyweight) and limit carbs to 50 grams a day, or preferable closer to 20 grams, if possible.
Depending on your individual status, getting fat adapted may take anything from 2 to 6 weeks. You will probably feel lethargic at first. But once you’re fat adapted, your energy levels will sky rocket and you will feel a new level of clarity. This is a good time to introduce some carbs before and after your training. With improved insulin sensitivity and somewhat depleted glycogen stores, the carbs will be soaked up by your muscles – aiding in anabolism and reducing the risk of catabolism.
There is a saying, that you should earn your carbs. And once you do, they make everything better!
Your autonomic nervous system and your innate circadian clock
It’s important to realize that your body operates around a 24-hour cycle that dictates your innate circadian clock. This clock help all living organisms to coordinate their biology and behavior with a daily day and night cycle. During the day, your sympathetic nervous system (SNS) puts your body in an energy spending active mode, whereas during the night your parasympathetic nervous system (PSNS) puts your body in an energy replenishing relaxed mode. Your SNS is stimulated by fasting and exercise and keeps you alert and active with an increased capacity to resist stress and hunger. This was crucial to our survival as we needed to hunt and collect food during the day. And as night approached, your PSNS, which is stimulated by your nightly feeding, makes you relaxed and sleepy. It also shifts the body to increase its capacity to digest and absorb nutrients. This is how your autonomic nervous system is meant to operate under normal conditions.
It’s therefore important that you try to plan your Intermittent Fasting according to your biology. This means that Intermittent Fasting variants where you eat earlier in the day and fast during the evening is far from ideal. You will feel and function better if you fast during the day and eat in the evening.
If you have a large meal during the day, you’ll inhibit your SNS and instead turn on the PSNS, which will make you sleepy and fatigued rather than alert and active. This is what is known as “breaking the fast”. Exactly how much you need to eat to shift into your PSNS is hard to say, but a common recommendation that worked well for me and my clients is to keep any kind of nutritional intake below 100 kcal, preferable closer to 50 kcal during the fasting window.
Wait a minute? Consume nutrients during the fast? Isn’t that some sort of sacrilege? Not necessarily. If done right, it opens up for variations that are more suitable for highly active athletes, athletes carrying a lot of muscle mass and people with a pretty low amount of body fat looking to get really ripped (as in bodybuilding contest ready).
Defining your net fasting state
We also need to define your actual time spent in a fasting state. By doing this, we need to separate the time we go without food from our actual net fasting state. If we take the regular 16/8 fasting approach which have a feeding window of 8 hours, most proponents say that they’re in a fasting state for the remaining 16 hours. But that’s not true. What really count is your net fasting time. What I mean by this is that you need to take digestion into account. It typically takes your body between 5 to 6 hours to fully digest a meal (depending on your meal density, i.e. the content of protein, fat, fiber etc.) And if the meal is very big, as it usually is when following an Intermittent Fasting plan, it can take up to 8 hours before you’re actually in a fasting state.
This means that if you, for example, finish eating at 9 pm, your body will not shift into a fasting state until about 2 to 3 am. And if you start eating again at 3 pm, you’re actual net fasting state is only 12 to 13 hours – and not 16 hours! And if you finish off your feeding window with a big hearty meal, your net fasting state might be as short as 10 hours.
These variations in net fasting state can make a big difference, especially if your goal is health related, such as improving insulin- and leptin sensitivity and possibly extending your life span – as the best effects are seen after 16 hours of being in a net fasting state.
If your goal is athletic performance and/or retaining or building muscle mass, you might need to compromise the length of your net fasting state to simply have enough time to get all the nutrients and calories you need. However, there are options – as you will learn in part 2.
That covers the basics of Intermittent Fasting and some of my thoughts and experiences. In the next and final part, we’ll look at the three most popular approaches among my competing clients.
References, sources and further reading: