Written by Samuel Biesack
Intermittent fasting (IF) is a diet protocol that in recent years has gained momentum as an alternative dieting method. More often than not, the most talked about style of IF is the one incorporating a 16 hour fasting period followed by an 8 hour eating period. While many are open to the idea and interested in the potential benefits that it can provide, some don’t exactly know how to start.
Uncertainty revolving around the idea of fasting for so long is not only legitimate, but may actually cause you to unsuccessfully transition to IF. Further, many are concerned that the fasting period will diminish their hard earned gains made in the bulking season, making the transition both mentally and physically difficult. However, there are some measures you can take to ensure that the transition is smooth and easy and that your hard earned gains will remain intact.
How do I start to do Intermittent Fasting?
One of the biggest reasons that people plateau or fail with a weight loss diet is that they do too much, too soon. We all know the person that went from eating 3500 calories to 1500 overnight because they got the sudden motivation to get rid of some of that winter weight. I’ve been there and chances are, you have too.
The same principle applies to fasting. When transitioning to IF, you have to remember that for an extended period of time, you’ve been eating pretty regularly throughout the day. These feeding patterns are not only ingrained mentally, but may actually regulate hormonal signaling as well. A study by LeSauter et al., (2009) showed that the stomach actually has cells that secrete ghrelin in response to regular feeding patterns. Ghrelin is a primary hunger hormone in the body that when secreted, increases hunger. LeSauter et al., showed that when you have a typical schedule of eating, ghrelin is secreted in response to when the body expects there to be food. As a result, during the preliminary transition period to IF, you can expect to become hungry at regular intervals, thus making it more difficult to adhere to.
Thomas et al., (2015) also did a similar study and found that insulin and free fatty acid (FFA) response to meals is primarily contingent on your typical eating schedule – eating or skipping breakfast, for instance. If you slowly introduce longer periods of fasting over to course of a couple weeks, you’ll hypothetically be more inclined to adhere to the fasting period and reset your hormonal response to eating.
If you typically eat immediately upon rising in the morning, a good place to start is to try waiting an hour after waking to consume your first meal. Every day after that, try increasing the fasting period by 30-60 minutes until you hit 14-16 hours. This is a sure fire way to increase the fasting period at your own pace in a way that will increase the likelihood that you’ll stick to the program. Alternatively, if you do decide to begin fasting the full duration right out of the gate, be cognizant of the fact that you may be very hungry during that time period for days or even weeks.
Which supplements should I use?
If you can handle supplements such as caffeine, the fasting period is a perfect time to use them. This is true for a couple of reasons. Stimulants such as caffeine have anecdotally been shown to reduce hunger cravings. Even the most experienced intermittent faster will tell you that it’s not uncommon to get hungry from time to time, so responsible use of caffeine can potentially stave off those hunger pangs.
Further, the fasting period seems to up-regulate sympathetic nervous system output. This means that during the fasting period, you have an increase in catecholamines such as epinephrine and norepinephrine. These catecholamines not only can switch substrate utilization towards fatty acids, but can also increase mental focus and clarity. This combined with caffeine can allow you to stay focused and mentally clear while mitigating hunger.
Should I track my intake?
The majority of research indicates that in order for you to lose weight, you should have negative energy balance. That means you either need to eat less than usual or expend more energy than usual at the same calorie amount. A big mistake that many intermittent fasters make is assuming that IF holds some magical power of causing fat loss in the absence of a calorie deficit.
While IF potentially promotes an increase in fat oxidation (Heilbronn et al., 2005), said increase may not result in weight loss unless you are in a calorie deficit. As of right now, it is highly likely that individuals that have had success with IF did so because they ended up eating less total calories over an extended period of time. Until an abundance of research is done indicating that it works in the absence of a deficit, it makes sense to be in a caloric deficit even if you are intermittent fasting for changes in body composition.
Additionally, by tracking intake, you can ensure that you don’t wind up binging during the eating period. Further, if your primary goal is to lose bodyweight or fat, tracking your intake can ensure that you are actually eating fewer calories. It’s amazing how bad we as humans are at estimating intake, especially on the level of actually counting calories.
By tracking your food, you can get an indication of just how much or how little you actually consume on a daily basis. Tracking may allow you to start observing eating patterns that are sabotaging your fat loss goals. As you become more experienced with recognizing how much you actually eat and correlating that with how the food you’re eating makes you feel, you can either choose to continue tracking or move away from it. However, when beginning the transition to IF, it is a sound idea to track intake to avoid eating too much or too little.
When should I train?
If you fast for 16-hours, train and then begin to eat, you’re actually fasting for much longer than 16 hours. That isn’t inherently bad but it results in shortening the eating period. If you care about at least maintaining muscle, you want to take advantage of your training sessions by eating for as long as possible, within your calorie goals of course. If you have a longer eating period, you can have smaller meals, which allows for better management of calories and a greater likelihood that you’ll consume an adequate amount of food.
A good place to start is to begin your training session 1.5-2 hours before the 16-hour mark. By the time you finish your training session, you can begin the eating period without shortening it.
How can I fast around my training?
Elaborating on the last tip, it is a good idea to base the fasting period off of when you train. If you typically train in the morning, IF may not be ideal. This is because you will have to begin the fasting period much earlier in the day and it may be extremely difficult to adhere to, yet not impossible. Training mid-day may be the most optimal for strict IF protocol adherence every day. If you train around noon, you can fast from 8 p.m. to 12 p.m. and eat until 8 p.m. the night of training. This creates a perfect cycle of fasting, training and feeding.
This idea becomes most important for those who train at night. If you fast throughout most of the day, train at night, and begin fasting as normal, you may be wasting opportunity to maintain or even grow lean mass. When you train, you increase protein synthesis, which is thought to be the primary driver behind adaptation to resistance training. For an untrained individual, this increase may be present for upwards of 48 hours (Tang et al., 2008). However, if you are of trained status, this increase in protein synthesis may only be elevated for 8-16 hours depending on the individual. Thus, if you are a trained individual, utilization of this increase becomes very important since the window is so small. If you train at night and begin fasting shortly after, you may be only utilizing a fraction of the duration that protein synthesis is elevated.
If you are a trained individual, it may be in your best interest to not fast the day after a nighttime training session. If you wake up the morning after a training session and continue eating, you are more likely to take advantage of the training session the night before in terms of increasing strength and at least maintaining lean muscle.
How long should I try IF for?
We all know that dieting is difficult – otherwise you probably wouldn’t be interested in alternative diet methods. Intermittent Fasting is no exception, at least for the transition period. As explained above, you’ve likely eaten frequently throughout the day for many years. It stands to reason that changing from a multi-year routine to one that incorporates extended periods of fasting may be difficult at the start.
Many people who intermittent fast anecdotally report decreased hunger during the fasting period. However, it is hypothesized that there is an adaptation period for this to occur. As such, give yourself at least a couple of weeks before deciding that IF isn’t for you, unless you’re absolutely miserable.
What should I eat when Intermittent Fasting?
One of the benefits of IF is that you get to avoid eating during the busy parts of your day and then feast later in the day. While it’s a great feeling to be able to eat a couple big meals at night and know you’re still within your calorie cap, it’s very easy to justify eating “less than optimal” foods that are high energy and low fiber.
While the jury is still out on whether or not the actual type of food you eat makes a serious difference in terms of body composition, you should error on the side of caution and make the majority of your intake high fiber, protein packed and nutrient dense. A really good way to accomplish this is moderate how you structure the way you eat.
Begin meals with the least satisfying components of the meal – this will likely be high fiber vegetables – and then follow with your protein. This may ensure that you eat what you need first, and then eat what you want afterwards. Further, by eating the high fiber and protein first, you’ll be less likely to over consume on the less beneficial parts of your meals.
Should I use whey protein?
Many proponents of IF are purists and recommend training completely fasted. However, the benefits of increasing protein synthesis via whey protein before training outweigh the unproven benefits of training totally fasted. In fact, Cribb et al., (2006) showed that ingestion of protein pre- and post-workout resulted in greater increases in lean body mass and decreases in body fat when compared to no intake peri-workout. Conversely, some studies such as those by Verdijk et al., (2009) and Wycherley et al., (2010) showed that muscle retention or gain was correlated with total daily protein intake rather than simply peri-workout nutrition. Nonetheless, it stands to reason that increasing protein synthesis before and after a workout via a complete protein source like whey, is still a good idea.
Taylor et al., (2013) showed that ingestion of protein before training did not blunt the training induced increase in AMPKa2 phosphorylation. Without getting too in-depth, AMPKa2 is one of the primary reasons that you would even consider training fasted. It’s an enzyme that is activated by muscle contraction and increases the ability for glucose to be stored in muscle specifically. It also plays a role in something called mitochondrial biogenesis or creation of new mitochondria. The more mitochondria, the greater fat oxidation capacity you have. Thus, if protein has no effect on this enzyme, it is likely beneficial to consume protein before hand. Lastly, many people suggest consuming BCAAs prior to training. Even though BCAAs will also increase protein synthesis, they don’t provide you with all of the remaining essential amino acids needed to sustain that elevation in protein synthesis whereas whey protein does.
The bottom line
The above tips are not the entire story of intermittent fasting. Primary research on resistance trained individuals using IF is lacking, but many anecdotally report phenomenal success. IF has time and again been shown to be a legitimate dieting alternative but the transition from a traditional diet may present problems for many. The above tips are ways that you can ensure your transition to IF is smooth and effective.
IF is not for everyone and it isn’t a magic plan but it seems to be effective for some. If weight and fat loss is your primary goal, make sure that you are in a calorie deficit. Further, if the transition is difficult, attempt to persist and make adjustments to the plan to suit you rather than switching immediately.
As with anything, the most effective diet is one that you’ll be able to stick to and stay consistent with. If you can effectively transition to IF, it may end up becoming a lifestyle rather than just another fat loss diet.
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