June 9, 2022
Navigating Intermittent Fasting

With so many different diets, meal plans, 30-day challenges and more it can be very difficult to get a hold on the best option for improving your health and fitness. Now I’d get Carpal Tunnel Syndrome before I could cover even 1/16th of what differing sources have to say on the matter, but what we will talk about today is how one can better navigate the popular trend of intermittent fasting safely and efficiently.

First, let’s break down what intermittent fasting is, what the goals are, how it can look, and good principles to follow if undertaking this method of eating.

Intermittent fasting is any of various meal-timing schedules that cycle between voluntary reduced-calorie intake (fasting) and non-fasting over a given period. A few popular methods of intermittent fasting include alternate-day fasting, periodic fasting, and daily time-restricted feeding. The American Heart Association states that intermittent fasting may induce weight loss, reduce insulin resistance, and lower the risk of cardiometabolic diseases. However, its long-term sustainability is unknown and adverse effects of intermittent fasting have not been studied comprehensively, leading some academics to point out its risk as a dietary fad. This is why I strongly encourage anyone looking into intermittent fasting to discuss thoroughly and collaborate with a professional before undertaking this route.

Now let’s go over the three methods mentioned above—which I personally would recommend over others, if any at all.

  1. Periodic fasting or whole-day fasting involves any period of consecutive fasting of more than 24 hours, such as the 5:2 diet, wherein there are one or two fasting days per week, to the more extreme version with several days or weeks of fasting. During the fasting days, consumption of approximately 500 to 700 calories, or about 25% of regular daily caloric intake, might be allowed instead of complete fasting.
  1. Alternate-day fasting involves alternating between a 24-hour "fast day" when the person eats less than 25% of usual energy needs, followed by a 24-hour non-fasting "feast day" period. It is typically the strictest form of intermittent fasting because there are more days of fasting per week.
  1. Time-restricted feeding involves eating only during a certain number of hours each day, often establishing a consistent daily pattern of caloric intake within an 8–12-hour time window. This schedule may align food intake with circadian rhythms.

Of all these it is the last, time-restricted feeding, that I would personally encourage someone to attempt if they are determined to try a fasting method. As a coach, the first and most important thing I want in all of my clients’ physiology is mental acuity. Time-restricted feeding is much easier to align with an individual's natural circadian rhythms (sleep-wake cycles), which promotes much more balance and overall health in every one of us, both physically and mentally. Essentially, if the fast is f*%&ing up your sleep, then the chosen method is harming more of a person's physiology than helping. A common problematic practice I’ve seen, for example, is skipping breakfast entirely and waiting for the first meal until the afternoon. This often leads to gorging later in the day, and often to eating late into the evening to the point that people are eating a couple hours or less before they head to bed…and then, due to the body having to work overnight digesting, they have poor quality sleep. This change in timing and effect on recovery has profoundly negative effects for both internal physiology and body composition. Our circadian rhythm dictates so much of our internal regulation. It helps determine when certain stress hormones are released and how much, when the thyroid is most and least active (usually most active between 12pm and 3pm so give it some fuel, dammit!), how and when the CNS ramps up and down, and more. All of these aforementioned systems are different in every individual, which is why understanding one’s own physiology and having professionals’ input can be so important. As with our workouts, one size does not fit all, and what works for one individual might have extremely varying results in another.

Now again, all of these methods can run the risk of circadian disruption. I prefer time-restricted because it can be manipulated in a way that does not impact the circadian rhythm and in fact works with it. I like to call this rule of thumb “eat with the sun” principle or, for my numbers people, the 16/8 rule (16 hours dedicated to fasting, 8 hours dedicated to non-fasting). This method can be easily aligned with daylight hours or a typical 9-5 schedule. So the principle is, during the allotted daylight hours/9-to-5 the person is allowed to consume, and once we reach sunset/5, the fasting will begin and last until sunrise/9. This promotes eating something in the relative morning hours (which I personally always recommend), affords a wide enough window that discourages gorging (which I personally rarely recommend), allows one to retain maximum mental acuity during daylight hours, promotes healthy hormone and stress regulation, and supports one in developing a harmonious relationship with the day/night cycle that every human operates on.

Again for the sake of transparency, fasting is not something I’d recommend in general, but especially not as a low-hanging fruit. I’d rather focus on creating more balance in the nutrient profile of one’s diet first and see if simple tweaks in timing, calories, and types of food couldn’t yield the results one is looking for without as much resistance and discomfort. There are many low-hanging fruits I’d want to pick off the tree first before seeing if intermittent fasting is indeed going to act as the ladder one needs to expedite their process in reaching their goals. That ladder is going to crumble if not set up correctly, based on the specific individual trying to use it. I hope this general introduction to the fasting method and a few guiding principles that I like to use are helpful.

In the end my job—our job—at Central Athlete is to support humans. So if you or someone you know is interested in intermittent fasting or other diets, workouts, methods, what have you, please contact us. One of our wonderful professionals would love to meet you where you are for a free strategy session and help set you up for future success.

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