The concept of meal timing… For quite some time now in the fitness industry.

Most gyms incorporate some sort of shake bar. The push to chug a protein-filled drink right after your workout has been taught to us by gyms from the moment we sign up! But is there any truth to it?

Before we get into the understanding of meal timing, let’s first define two important terms:

“Anabolic”

The process of building up, in this case, your metabolism. When your body is in a state of anabolism, you are building new compounds, tissues as well as muscles. In weightlifting, for example.

To produce this effect your body has to use building blocks like protein and amino acid and burns energy to use them [1].

So the words build and strengthen should be the first on your list when the word anabolic comes to mind.

“Catabolic”

This is the very opposite of anabolic metabolism.

Catabolic metabolism involves the breaking down of tissues and compounds. When your body is in a catabolic state it releases energy.

An example of this would be a long-distance runner. When your body is enduring a high-intensity exercise for a long period of time this tells the body to break down protein for energy, which in essence, breaks down muscle tissue as well.

This leads us to the phrase that has been debated:

“The metabolic window”

The metabolic window is a term used to tell people that if they don’t take in a specific amount of nutrients after an intense workout, they will lose the potential to gain muscle mass in the gym.

With studies constantly contradicting both, this subject has been examined for quite some time.

But it makes sense right? Feeding the body after it’s been through hell sounds like a precise way to feed the muscles. If you don’t take in a combination of fast-acting carbohydrates mixed with a high amount of protein, you won’t gain the muscle mass you always wanted…right?

To get a complete understanding of this theory we need to review all the studies available.

Now let’s take a look at the facts.

(SHOW ME THE CARB FAX! HA GET IT 8) )

Some studies proved it has no effect.

A study by Camera et al. claimed that low muscle glycogen concentration (no post-workout carb/protein) combined with HITT did not compromise the body’s anabolic signal, therefore, having no effect on muscle loss. [4] (but what about them gains?)

Let’s see what the other side has to say…

Does the combination of carbohydrate (CHO) and Protein (PRO) after a workout lead to anabolism?

A few studies say yes.

A study done in 2006 involved 4 control groups that were given different macronutrients post-workout, CHO, EAA (Essential Amino Acids), CHO + EAA, and PLA (placebo). The findings showed that the synergistic effect of CHO+EAA maximizes the anabolic response [5].

Another study in 2002 also found that there was an enhanced benefit to supplementing with protein and carbohydrates early post-exercise as well. [10] Even a study dating back to 1997 has tested this to be true [11]

So yes, according to these case muscle gain is achievable with the help of CHO and EAA! But why is there so much controversy?

There may be many opposing views on the building of muscle with nutrient timing supplementation.

But it is indefinite that this can benefit athletic performance (CHO specifically).

A study by Fielding RA examined a group of 9 men during 4-hour cycling bouts and separated them into groups of different macronutrients post-workout to determine the effect of frequency and dosage of carbohydrates on muscle glycogen utilization.

Findings stated that the group taking in a moderate amount of CHO during a workout performed significantly longer than the group taking an artificial sweetener of the same amount. (Artificial sweetener group, you have been… bamboozled) [6]

So does the amount of Carbohydrate matter as well?

According to Fielding RA’s study as well as a study done by Roy B.D, the amount matters just as much as the type of macronutrient. [11]

With another study finding proof that carbohydrate enhances performance also contradicts Fielding RA’s findings slightly. In his study, he presented an experiment involving 12 men performing a 45-minute cycling bout after either a 3-day high CHO diet or a low CHO diet.

The conclusion was drawn that those on the low CHO diet did not differ significantly from the high CHO group. (perhaps longer periods of time are more beneficial for CHO-diets/specific intake of CHO..?, interesting!)

CHO and the 24-hour window. Carb loading for better performance.

What is carb loading?

“Carb-loading” is a strategy used to improve athletic performance for endurance events by increasing the amount of fuel stored in your muscles. This is done by taking a full-body rest day while also ingesting a high-carbohydrate diet a day prior to an endurance event. [13]

It has already been established that athletes can store maximal amounts of muscle glycogen within 3 days of ingesting a carbohydrate-rich diet, (the more you know!)

But can it be done in a shorter time with the same effect? (dun, dun, dun…)

Results from a study done by Bussau VA demonstrate that CHO loading CAN reach peak velocity in a minimum of 24 hours with a lack of physical activity. (Isn’t the human body magnificent?)

So having a rest day before your big game with an increase of CHO will enhance your performance drastically!

(Rest day=potentially more carbs? *thinking face*(woohoo!))

There is also evidence that consuming a CHO-high diet for 1-3 days and then partaking in both aerobic and anaerobic exercise on the same day will achieve super-compensated muscle glycogen that lasts longer than choosing the anaerobic workout as their first choice of exercise. [7] (let’s just say your muscles are going into superhero mode B) )

What if we take protein before a workout instead of CHO?

Studies in the past concluded that protein consumption close to a workout increases muscle protein synthesis. More so than ingesting carbohydrates alone close to workout time. [9]

But.. what if one type of protein had a greater effect on fat loss/muscle gain?