Why? Well… dieting tends to be hard. From cutting calories and dealing with hunger, to maintaining exercise at a high intensity and recovering with a low energy intake there will be barriers that often make you want to quit.
When traditional dieting methods of cutting calories just aren’t working for you, Intermittent Fasting (IF) may be the answer, or at least a technique you want to consider. Often referred to as time-restricted feeding, Intermittent Fasting incorporates a daily schedule of fasting and feeding, with the feeding period typically being placed around the training session.
Intermittent Fasting boasts a myriad of benefits that extend further than simply helping you lose body fat and maintaining muscle. Surprisingly, in some cases it seems to do so better than traditional calorie restriction alone for both fat loss and improving metabolic health (4). I’ve applied these techniques into my 90 Day Bikini plan and work with personal clients, the results are amazing (you can see some here).
Here’s an overview on Intermittent Fasting, what it is, how it works and why it’s beneficial.
Different Types of Intermittent Fasting
There are different types of Intermittent Fasting. Based on your primary goal and schedule, you should choose the method that works best for you. These are some of the most common Intermittent Fasting approaches for exercising individuals.
The Lean Gains Approach: 16 hours of fasting, followed by 8 hours of feeding with most food in the post-workout period; the traditional Intermittent Fasting technique for resistance training individuals.
Training Modulated Intermittent Fasting: 16 hours of fasting, followed by 8 hours of feeding on alternate days, with off days being the day after training. This is a modified approach of Lean Gains for maximum muscle retention and possibly growth.
Warrior Diet: Fasting most of the day, allowing for one large meal, preferably close to bedtime, in the post-workout period.
Alternate day fasting: One day of almost complete fasting (approximately 1/4 maintenance caloric intake), alternating with maintenance calorie intake on off days.
Rudy’s Protein Fast: This is my own edited and optimized version of intermittent fasting tailored to people who workout at a serious level and want to drop body fat but also support their training and muscle growth / recovery. With this, you will perform a similar 8/16 fast (8 hour feed, 16 hour fast), but, with a difference. Within the 16 hour fast, you will have 2x 30-40g whey protein shakes to stimulate MPS and optimize muscle growth/retention. Because this is pure protein, it will add a very small amount of calories without negating the ‘fasting window’.
What Are Potential Benefits Of Intermittent Fasting?
Some research indicates that practising intermittent fasting may provide benefits to a greater extent that traditional calorie restriction alone. The following benefits seem to be the most profound as a result of practising Intermittent Fasting:
- Insulin Sensitivity
Insulin Sensitivity seems to be increased following intermittent fasting protocols (3).
Increased insulin sensitivity allows for an optimal response to food intake, allowing energy uptake into the appropriate tissue in an efficient way. This can help reduce the likelihood of developing diseases such as Type 2 Diabetes and reduced the chances of storing excess body fat (1).
- Increased adiponectin in circulation and the brain
A recent study in trained individuals revealed fasting may increase levels of a hormone called adiponectin. Adiponectin plays an immense role in regulation of glucose as well as fatty acid oxidation (3,4).
In fact, when levels are increased in circulation, it can potentially prevent new fat cells from being formed. When increased in the brain, it can have a thermogenic effect by increasing energy expenditure. The kicker? A human study indicated increased adiponectin and greater fat loss for individuals who fasted, when compared to a normal diet, even when calorie intake was equal! (4)
Surprisingly, having regular extended periods of fasting can actually decrease hunger while dieting. This is largely due to suppression of cells that secrete the hunger hormone, ghrelin, during the fasting period (2).
- Increased fat loss compared to equal calorie, normal diets
Interestingly, some studies have actually indicated that periodic fasting can lead to increased fat loss, when compared to normal diets alone (1, 6, 5).
It was originally theorized that this was due to consumption of less calories in the long term. However, a recent study by Moro et al., indicated that even when calories were matched, fasting participants observed greater fat loss than those dieting alone.
How To Perform Intermittent Fasting
As noted above, there are different forms of Intermittent Fasting. Ensure that you choose the form that fits best with your schedule in order to be consistent and successful.
When beginning a fasting protocol, you should consider working your way up to fasting for the traditional 16 hours. Otherwise, you run the risk of being too hungry and falling off the wagon.
A good place to start is to fast for 12 hours. Once you’ve achieved this, increase the fasting period by an hour every day until you reach that elusive, 16-hour mark.
Around the 15-16 hour mark is when you should consider training. A primary goal of Intermittent Fasting is to allow the post-workout window to include the 8 hour feeding period in order to take advantage of the training stimulus, and maintain your hard earned muscle.
Based on the already small feeding window, it may be in your best interests to actually exercise around the 15-hour mark so that you can take full advantage of the 8-hour feeding period.
Intermittent Fasting Example Day
The Lean Gains Approach (16:8):
- 8 p.m. the night before training: Last meal
- 11:00 a.m. the next day: Exercise session
- 12:00-1:00 p.m. Meal 1
- 4–5 p.m. Meal 2
- 8 p.m. Meal 3 (last meal of the day)
My Example Alternative Day Protein Fast
- Day 1, eat as normal focusing on healthy foods and high protein
- Day 2, consume 40g whey protein in the AM and PM
- Repeat this 2 day rotation
Rudy’s Example in the 90 Day Bikini Fasting Protocols
- Fast until 9am
- 9:00 a.m. Protein Shake
- 12:00 p.m. Protein Shake
- 2:00 p.m. Meal 1
- 6:00 p.m. Meal 2
- 10:00 p.m. Meal 3 / Protein Snack
What Food Do You Consume When Intermittent Fasting?
There is no set diet that you follow when doing Intermittent Fasting. In fact, the whole dieting principle around Intermittent Fasting is the actual fasting windows; therefore, there are no actual specific food or dieting principles.
Quite simply, when you are within the ‘eating window’ you can consume a normal and balanced healthy diet. This can be a mix of carbs, protein and fat, based on single ingredient foods.
The benefits of Intermittent Fasting is that it allows you to eat more at each meal, as you obviously have a smaller feeding window per day. Many people, myself included, would sooner have fewer meals when dieting, but enjoy them all the more, as they are larger and provide satiety or fullness rather than 5 small meals per day.
Although I don’t really recommend this long term, Intermittent Fasting also allows for more ‘bad’ food or ‘cheat meals’ as you are saving calories all day for that small feed window. While you shouldn’t do this daily, as some people do, I like this method when heading to a social event or dining out. It allows me to have more freedom in a restaurant, without feeling restricted or going way over my calorie / macro limit for that day.
Is Intermittent Fasting For You?
Intermittent Fasting incorporates prolonged periods of time fasting. This can often be difficult for people.
It is a good idea to give yourself at least two weeks of practising, before making a decision whether or not to practise intermittent fasting.
As mentioned earlier, be sure to start with a modest but meaningful fasting duration such as 12 hours, and then work your way up to 16 to 20 hours, based on the form of Intermittent fasting that you choose to utilize.
This can allow you to get a headstart on some of the potential benefits of Intermittent Fasting, but not risk opting out after a couple days due to hunger and irritability.
As with many other forms of dieting, Intermittent Fasting requires a period of time ranging from 1 to 2 weeks in order to adapt to the new schedule of fasting and feeding.
Lastly, it must be noted that Intermittent Fasting is not an excuse to binge on less than ideal foods. As with any diet, it is always suggested that you consume high quality, protein and fiber rich foods, during the feeding period.
By doing so, you will provide your body with the essential nutrients to recover and put yourself on the fast track to the body you want.
If you do want a proven Intermittent Fasting diet plan and protocol, along with 30 advanced workouts and my famous transformation plan, you can learn more about the 90 Day Bikini Challenge here:
- Heilbronn, L. K., Smith, S. R., Martin, C. K., Anton, S. D., & Ravussin, E. (2005). Alternate-day fasting in nonobese subjects: effects on body weight, body composition, and energy metabolism. The American Jjournal of Clinical Nutrition, 81(1), 69-73.
- Lesauter, J., Hoque, N., Weintraub, M., Pfaff, D. W., & Silver, R. (2009). Stomach ghrelin-secreting cells as food-entrainable circadian clocks. Proceedings of the National Academy of Sciences, 106(32), 13582-13587. doi:10.1073/pnas.0906426106
- Lihn, A., Pedersen, S., & Richelsen, B. (n.d.). Adiponectin: Action, regulation and association to insulin sensitivity. Obesity Reviews, 13-21.
- Moro, T., Tinsley, G., Bianco, A., Marcolin, G., Pacelli, Q. F., Battaglia, G., . . . Paoli, A. (2016). Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. Journal of Translational Medicine, 14(1). doi:10.1186/s12967-016-1044-0
- Varady, K., Bhutani, S., Church, E., & Klempel, M. (2009). Short-term modified alternate-day fasting: A novel dietary strategy for weight loss and cardioprotection in obese adults. American Journal of Clinical Nutrition, 1138-1143.
- Varady, K., Bhutani, S., Klempel, M., Kroeger, C., Trepanowski, J., Haus, J., . . . Calvo, Y. (n.d.). Alternate day fasting for weight loss in normal weight and overweight subjects: A randomized controlled trial. Nutr J Nutrition Journal, 146-146.