Fasted Training

Early Morning Fasted Training – General Position:

The fasted phase is that it should last through the night and during the morning hours. Ideally the fast should then be broken at noon or shortly thereafter if you arise at 5-6am like most people in training. Afternoons and evenings are usually spent in the fed state.

Reasoning :

“The recommendation for fasting through the earlier part of the day, as opposed to the latter part of the day, is for behavioral and social reasons. Most people simply find it easier to fast after awakening and prefer going to bed satiated. Afternoons and evenings are times to unwind and eat. For adherence reasons during dieting, I’ve also found that placing the feeding phase later in the day is ideal for most people.”

This poses a dilemma for those who can only train in the early morning hours. If you’re training first thing in the morning and finish at 7am it would call for a feeding phase of 7am to 3pm. That’s just a bit too early for my liking. Could you still do it and start the fast in the middle of the day? Sure. But generally speaking, this would compromise diet adherence for most people.

Seeing that most my clients wants to lose fat, optimal diet adherence is high on my priority list. I always aim for a diet design that is easy, painless and maintainable in the long term. So how have I solved this dilemma, knowing the importance of pre-and post-workout protein intake?

The protocol

Most advocates maintain their 8-hour feeding-window between 12-2 pm and 8-10 pm on all days. For those doing early morning fasted training I have maintained that feeding window and added small feedings of BCAA pre- and post-workout.

Similar to fasted training, 10 g BCAA is ingested pre-workout. However, instead of initiating the feeding phase immediately post-workout, which is the standard protocol for regular fasted training, another 10 g BCAA is ingested two hours after the first. A third dose may then be ingested depending on when the client prefers his feeding-window.


Early morning fasted training

Here’s a sample setup for a client that trains early in the morning and prefers the feeding phase at noon or later.

  • 5 am: 5-15 minutes warm-up, 10 g BCAA.
  • 5:15 to 7 am: Training.
  • 8 am: 10 g BCAA.
  • 10 am: 10 g BCAA.
  • 12-1 pm: The “real” post-workout meal (largest meal of the day). Start of the 8 hour feeding-window. # Ideally, break the fast with your largest meal (higher carbs) and taper caloric content of meals downwards throughout the day.
  • 8-9 pm: Last meal before the fast. For the sake of convenience,  # End, the 8-hour feeding window with a (lower carb) meal containing slow digesting protein such as cottage cheese or eggs. Meat served with fibrous veggies is another option (meat is a fairly “fast” protein, but fiber will slow digestion). I recommend getting BCAA in the form of powder and not tabs.

Simply mix 30 g of BCAA powder in a shake and drink one third of it every other hour starting 5-15 minutes pre-workout. Tabs are cheaper, but much more of a hassle (you’re going to have to pop a lot of tabs). 

Protein synthesis

I had some concerns before deciding on incorporating and recommending this protocol on a wider scale. After rigorous testing, these concerns have not proven to be valid.

My first concern was that results would be compromised if the post-workout meal was pushed back several hours. I haven’t seen any trend, such as lack of progress or loss of strength and muscle mass, to indicate that this is the case. The results are on par with those obtained with the other protocols.

Consuming BCAAs every other hour through the fast is sufficient to keep protein synthesis stimulated and prevent protein breakdown. If protein intake is completely omitted, it would undoubtedly affect results negatively. Thus the compromise of ingesting BCAA pre- and post-workout through the fast, before the real post-workout meal, which is initiated at the usual time of the feeding phase.

Will we still derive the benefits from regular fasting if we consume small amounts of protein throughout the fast post-workout? Yes. If carbs are omitted, the increased insulin sensitivity will quickly bring back basal insulin to fasted state levels despite consuming 120 calories worth of fairly insulinogenic amino acids (30gram BCAA’s). The fasted state is almost fully maintained post-workout.

When the post-workout meal comes around is also when muscle protein synthesis is beginning to take off. Though muscle protein synthesis is acutely stimulated post-workout in response to resistance training and protein intake, studies show some latency in regards to elevation and peak. Protein synthesis starts to climb about 3-4 hours post-workout, reaches a peak at the 24-hour-mark and returns close to baseline values 36 hours post-workout (or 48 hours depending on who you ask; studies on this topic show slightly different results regarding length and peak of elevation). Even if you push back the post-workout meal a few hours, you will be in the fed state at a time when nutrient partitioning is optimized and muscle growth likely to occur.

By consuming small amounts of BCAA through the fasted state we are stimulating synthesis and halting breakdown. A few hours later, when protein synthesis is increasing, we enter the fed state. The latency seen with protein synthesis in response to training, and the fact that we have amino acids (BCAA) in circulation pre- and post-workout, goes a long way in explaining why clients following this protocol get equal results to those following other protocols.

Hunger and hypoglycemia

My second concern was that clients would be hungry or suffer bouts of exercise-induced hypoglycemia post-workout. This would compromise diet adherence and/or impair productivity during the fast and make the protocol worthless. Fortunately, this has not been proven to be the case.

For some it will feel unnatural to not eat directly post-workout. This is part of a learned response. After a training session we want to reward ourselves . Even if there is no real physiological need to do so immediately. If anything, high-intensity exercise in the fasted state tends to suppress appetite in the short-term and not increase it.

This is mirrored by my personal experience as well. If I train within the hour upon awakening, I still don’t get hungry until the time I am used to eating – which may be 4-5 hours post-workout. Clients have reported the same.

There are no hypoglycemic episodes reported so far, but this was only a true concern of mine for those involved in fairly glycogen-demanding training such as CrossFit. Considering that there’s a fair amount of liver glycogen available to maintain blood glucose levels during training after an overnight fast this is not so strange.

The only way I could imagine someone experiencing hypoglycemia post-workout, if a post-workout meal was delayed for several hours, would be after prolonged and strenuous training in combination with severe calorie or carbohydrate restriction. In such a case the training session would induce a substantial and acute energy deficit along with complete depletion of liver glycogen content (which would escalate protein breakdown and also increase the risk of hypoglycemia). I am not a fan of prolonged endurance training in the fasted state.

For others, hypoglycemia is not a concern. Even type 2 diabetics maintain blood glucose very well in the hours following fasted state training in spite of not eating post-workout. For a metabolically healthy individual, there is nothing to worry about.

BCAA vs whey

What’s all this fuss about BCAA and could we not use another protein source such as whey protein? Strictly speaking, no. BCAA contains the three major amino acids intimately involved in activating muscle protein synthesis, including leucine which is the key player. Whey protein contains 25% BCAA. Other high-quality protein sources, such as meat, contain 17-18% BCAA. To get an equivalent amount of BCAAs into circulation during the fasted state would require 120-180 g protein from these sources. That’s more than 500 calories (120 g protein plus tag-along carbs and fat), which is not far from a medium sized meal.

With BCAAs we are getting maximal benefits with regards to muscle protein synthesis for a minimal caloric load. The latter point being important to maintain the fasted state and to allow for a liberal 8-hour feeding window later in the day.


If all this sounds like micromanaging to you, that’s exactly what it is. Inquiring minds would probably like to know what, if any, benefits there are in maintaining a fasted state a few hours post-workout when it comes to muscle growth and recovery. But I’d be hard pressed to make such arguments when there aren’t any. The real growth takes place later in the day, when the feeding-window is initiated. Until then we make sure that:

* Muscle protein synthesis is stimulated and protein breakdown inhibited by regular feedings of BCAA pre- and post-workout.

* Appetite is suppressed and insulin sensitivity maintained throughout the fast.

* The feeding-window is initiated at the usual, entrained, time point.

This is how I have solved the dilemma of early morning fasted training without compromising the results .

Key points

* No calories are to be ingested during the fasted phase, though coffee, calorie free sweeteners, diet soda and sugar free gum are OK (even though they might contain trace amount of calories). A tiny splash of milk in your coffee won’t affect anything either (½-1 teaspoon of milk per cup at the most – use sparingly and sensibly if you drink a lot of coffee). Neither will sugar free gum in moderation (~20 g).

* The fast is the perfect time to be productive and get things done. Don’t sit around, get bored and brood about food.

* Meal frequency during the feeding phase is irrelevant. However, most people, including me, prefer three meals.

* The majority of your daily calorie intake is consumed in the post-workout period. Depending on setup, this means that approximately 95-99% (fasted training), 80% (one pre-workout meal) or 60% (two pre-workout meals) of your daily calorie intake is consumed after training.

* The feeding window should be kept somewhat constant due to the hormonal entrainment of meal patterns. We tend to get hungry when we’re used to eating and maintaining a regular pattern makes diet adherence easier. If you’re used to breaking the fast at 12-2 PM and ending it at 8-10 PM, then try to maintain that pattern every day.

* On rest days, meal one should ideally be the largest meal, as opposed to training days where the post-workout meal is the largest meal. A good rule of thumb is to make meal one on rest days at least 35-40% of your daily calorie intake. This meal should be very high in protein; some of my clients consume more than 100 g of protein in this meal.

* Be open to compromising on the above rule. If your preference is to eat a larger meal in the evening instead of noon, or whenever you break the fast, it’s no great harm. Some people prefer to save the largest meal on rest days for dinner with their family instead of having a large lunch and that’s fine by me if it makes them enjoy and adhere to their diet better.

* Macronutrients and calorie intakes are always cycled through the week. The specifics depends on your ultimate goal: fat loss, muscle gain or body-recomposition. More details later. Generally speaking, carbs and total calorie intake is highest on training days. On rest days, carbs are lower and fat is higher. Protein is kept high on all days.

* Here are the supplements I recommend everyone to take on a daily basis: a multivitamin, fish oil, vitamin D and extra calcium (unless dairy is consumed on a regular and daily basis).

* For fasted training, BCAA or an essential amino acid mixture is highly recommended. However, if this feels like too much micromanaging or simply questionable from an economic standpoint, you could also make due with some whey protein. The importance of protein intake prior to fasted training is outlined in this and this post.

* Which protocol is best? I tend to look at things from a behavioral perspective first and foremost, so my reply to that is to choose the protocol best suited to your daily routine and training preferences. If you work a 9-5 job and your only option is to train after work, training fasted is generally a bad idea and I always choose the one or two meals pre-workout protocol.

* Even from a physiological perspective, each protocol has it’s own strengths and theoretical benefits. With “physiological perspective” I mean in terms of nutrient partitioning, fat loss and muscle growth. This deserves an article on it’s own.