A good number of people perform some form of Intermittent Fasting (IF) due to a variety of reasons. Many people across the globe practice it due to religious reasons. IF is nothing but fasting done intermittently, where you consume no food/water during the fasting period.
The question that I often get while helping such clients is, “How do I manage my nutrition/training while following the fast?”
That is the reason I decided to write this article. I am not going into the details of how you should be fasting as that is different for different people. Essentially, it means that you are not consuming calories. I shall rather go into pointers and discuss how you can manage your schedule in the feeding window. There is some information for the science nerds as well.
1. Stay hydrated
Dehydration can lead to a lot of health issues ranging from reduced performance (energy levels) to serious issues like kidney stones. In many of the fasting protocols, water is a no-go in the fasting state. But it should be given high priority during the feeding period.
There are three ways in which you can determine what should be your water intake:
- The metric or imperial system for water intake as mentioned in the table below. As I largely follow the metric system, a good guideline is 1 liter of water per 23 kilos of body weight.
- Environmental factors play a huge role. A person who lives in a cold region is likely to lose less water through sweat compared to someone living in desert-like conditions. Thus, a higher fluid intake is desirable for someone living in hot weather conditions.
- Recommendation by Lyle McDonald in his website bodyrecomposition.com states that you should be having 5 clear urinations per day, 2 of them coming shortly after your workout or during the workout if your sessions are longer. 
Source: The Muscle and Strength Pyramid by Eric Helms
What counts in the fluid intake? Any fluid except alcohol. Yes, even supposedly dehydrating things like ‘black coffee’ counts in fluid intake. So you can consume teas, coffees, diet drinks, water, etc. for your fluid intake. 
2. Eat protein
Protein is one of the most important macronutrients when it comes to preserving lean body mass (LBM) and performance. A good guideline for protein consumption would be anywhere between 0.8 – 1.0 gram/lb. of LBM.
For people who regularly engage in resistance training, a good range would be between 0.8 – 1.3 gram/lb. of total body weight.
There have been studies which suggest that higher protein intakes have some benefit in terms of satiety and tends to reduce overall energy consumption. [3,4]
3. Fiber intake
Fiber performs a host of functions like increasing satiety, taking care of gut health and reduce overall energy consumption. These things can ensure that the digestive tract stays healthy while following any kind of a diet or eating protocol. 
A good guideline for women would be to consume a minimum of 20 grams of fiber and for men would be a minimum 25 grams of fiber per day. For those following a lower calorie or low-carbohydrate diet, a good guideline is to consume 10 grams of fiber per every 1000 kcals being consumed. The absolute upper limit would be 20% of your carbohydrate intake. More is not always better and in some cases, even detrimental to gut health and bodies ability to absorb some nutrients.
Source: The Muscle and Strength Pyramid by Eric Helms
Having fruits and vegetables in your diet is a good way to have the required fiber intake. The above picture gives you a good range for your daily requirement of fruits and vegetables.
4. Minimize fat intake
Many times, fasting due to religious regions is followed by feasting. When you are feasting, you have a variety of options to eat from. Now, if you understand macronutrients, you should be able to easily figure out foods high in fat and foods high in carbohydrates.
Anything that is deep-fried or has a lot of dairy, nuts or eggs used in preparation, is usually high in fat.
It is usually a good idea to have a higher carbohydrate diet over a higher fat diet or choosing high carbohydrate food options over high-fat food options.
The reason I make this recommendation is that during such a fast, majority of people are eating in a caloric surplus. The macronutrient composition of your diet does determine how much fat you can put on while eating in surplus.
According to a 1995 study by Horton et al., there is a positive correlation between fat gain and macronutrient composition of the diet while being in a surplus. In this study, subjects were fed 50% additional calories either coming completely from carbs or fats. At the end of day 1, subjects who only had carbs only stored 10% of the surplus as fat whereas the fat group stored 60% of the surplus as fat. 
Even though this evened out over the course of two weeks, other studies do suggest that de novo lipogenesis (conversion of carbs to fat) is not a major source of fat storage of acute overfeeding. Carbohydrate overfeeding in the long term leads to reduced rate of fat oxidation, meaning more fat available for storage.
5. Do some training (it is NEAT)
Training in your feeding period or training, in general, is a great idea to burn extra calories at any given day. So make sure that you get in some form of training on a regular basis. Having a better body composition with a good lean body mass (LBM) has a host of short-term and long-term benefits. So, prioritize resistance training over cardiovascular training.
There is research that suggests combining resistance training with a hypocaloric diet helps in the preservation of LBM. 
If you have intermittent access to a gym or are just beginning out, this home workout routine could be a good start:
Studies also suggest that while eating in a surplus, your body’s energy expenditure increases (decreases in rare cases) due to spontaneous physical activities like fidgeting, sitting in a particular posture, etc. Thus, there is a good chance that you are burning more calories subconsciously while eating in a surplus. 
6. Have bulk, cut and maintenance days (give yourself flexibility)
This is something that I am a huge proponent of myself and have seen that it helps people sustain their progress even after a period of dieting. By following this approach, you can take out some rigidity from your program while still following a structured nutrition plan.
Let’s take an example, you have a macronutrient and calorie targets look like this:
The total calorie target of approx. 2230 which will help you maintain your weight.
Rather than sticking to these exact numbers, give yourself ranges. The targets would now look something like this:
P 135 to 165 (+/- 15)
C 230 to 270 (+/- 20)
F 60 to 75 (+ 5 or – 10)
The calorie range would now be between 2000 to 2415 where the lower end will result in some weight loss and higher end in some weight gain.
This gives you a bit more flexibility and you can eat more or less depending on a variety of factors.
Helms also proposes a 3-tier system which I myself use largely with my clients. It goes like:
Tier 1 – Try to stay within your macronutrient ranges (as mentioned above).
Tier 2 – Complete the protein intake for the day and remaining calories from fats or carbs or a combination of both.
Tier 3 – Just do not go overboard with your caloric intake for the day. The macronutrient split does not matter on these days. But capping calories does ensure that you are not hurting your progress significantly.
7. Follow the 80:20 rule
The 80:20 rule is not just a way to sustain a dieting phase in your life but also how you can manage or even make further progress in the long term. The image below gives a very simplistic picture of what you should be doing, i.e. eating nutritious food 80% of the time and enjoying things that you like the remaining 20% of the time.
If you apply the tier system here, you would want to be in Tier 1 (and/or Tier 2) for 80% of the time.
Now, this part of the article is completely a personal choice to read it or skip it. According to my experience as a coach, keep it simple when it comes to fasting for societal or religious purposes. Unless your aim is to get stage lean for a contest, event or a photo shoot, just try to maintain your current fitness levels during such phases. A great physique is an ultimatum for many people but trying to do it when there are a lot of uncontrollable factors can be stressful.
KISS (Keep it simple silly)
For the readers who do not have the time on hand and just want a brief of what the article suggests, here you go:
- Stay hydrated. Consume at least 1 liter of water per 23 kilos of bodyweight. If you live in hot weather conditions, push it up.
- Eat protein, a minimum of 0.8g/lb. of LBM to maintain your lean mass.
- Eat fiber as it will ensure your gut health stays fine and helps you remain satiated. Women should target 20 grams of fiber/day and Men should target 25 grams of fiber/day.
- Make sure you follow a diet which is low in fat if you will be eating in an energy surplus.
- If possible, do some resistance training. If not, do some home workout with some resistance.
- Be a bit flexible if you are following nutrition guidelines rather than being very rigid about it.
- Follow the 80:20 rule and enjoy the festive feasts in moderation.
- Antonio, J., et al., A high protein diet (3.4 g/kg/d) combined with a heavy resistance training program improves body composition in healthy trained men and women - a follow-up investigation. J Int Soc Sports Nutr, 2015. 12: p. 39.
- Shah, M., et al., Effect of a High-Fiber Diet Compared With a Moderate-Fiber Diet on Calcium and Other Mineral Balances in Subjects With Type 2 Diabetes. Diabetes Care, 2009. 32(6): p. 990-995.
- Turner, N.D. and J.R. Lupton, Dietary Fiber. Advances in Nutrition: An International Review Journal, 2011. 2(2): p. 151-152.
-By Pratik Thakkar
(Co-founder, GetSetGo Fitness)