PersonalFit – Tokyo personal training

The carbs-restricted diets

Brown sugar and wooden spoonFad diets: carbs are not evil, they serve you more than you think.

Let’s start on the topic of diets to avoid with the carbohydrate-restricted diets.


Whatever your current fitness level is and your current daily activity, your nutrition should always be made of the following nutrients in various quantities depending on your goals and activities:

  1. Carbohydrates
  2. Proteins
  3. Fats
  4. Vitamins
  5. Minerals
  6. Water

Those are mandatory and any lengthy lack of any of them would lead to systemic malfunctions in your body.

Carbohydrates (pasta, rice, starches, sugar..) are the main source of energy for your body, especially your brain, heart and muscles. I guess for some the latter is not that important but brain and heart may find a certain use in your daily life.

The main fuel for brain and central nervous system is glucose, which is most obtained by processing carbohydrates.


Why do carbohydrates got this bad reputation of fat gainer?

There are two reasons, but, one should consider one thing, please check the following table.

nutrientcalories per g

See? Carbs are with proteins the least calorific nutrients!

But something should not be overlooked, carbs and especially sugar are getting really fast in your blood, and what is not used, becomes fat. That’s why, “slow” carbs have a better reputation, for they diffuse slower in your blood stream.


Slow and fast carbs

  • So the first reason carbs are badly considered is the misuse of them, one should take the right carbs intake considering the next 3h expected level of activity.

A sudden intense effort would require fast assimilation of sugar, you can hit the juice can, no problem.

A lengthy moderate to high activity such as studying or running at average pace would require a low glycemic index intake before, such as brown rice.


  • Magazine showing the caveman dietSecond reason and the most insiduous one is the “paradigm effect”. Paradigm is basically something having a reputation, “because”.

Well that because comes from a diet born in the turn of the century: the “keto diet” or ketogenic diet, previously used to cure or at least soothe the most severe cases of epilepsy.

This diet, used and renamed as many times than a 80’s popstar, “caveman’s diet, cromagnon’s diet, and so on” referring to the time when human did not cultivate food, involving a very very low intake of carbs per day. If you think about it, most of the sugars and starches are coming from industry.

The effect of the keto diet  is that the body then falls back on its plan B, and starts to break down ketones contained in fat. Ketogenic diet… Got it?

Fact is that this diet takes time to settle, and your body takes up to three days to change from gas to diesel. Any little failure at not eating carbs directlly turns it back to normal mode. Carbs became suddenly the biggest evil.


Keto diet sounds like working, why criticizing it?

As a serious and curious trainer myself, I did it, for a month in December 2013, and it was hard. But ok , no pain no gain.

It worked, it worked badly well and I got my lesson:

My metabolism crashed and I started to lose weight in an uncontrolled fashion. I looked sick, bony on my face and it was scary because even back to regular nutrition it still went down for a little while.

That was a big mistake, a crashing metabolism on a muscular body just gets out of control, since the more muscle you have the faster you consume energy and I started to be seriously depleted to the point that I lost a serious mass of muscle in no time (I estimate a loss of 4kg of lean mass in a month).

My immune system went down, every little cold was caught and hard to deal with. Sympathetic and parasympathetic systems, responsible of pacing your whole metabolism, showed evidences of overtraining which is usually a very bad syndrome. Took me a while to recover and get back that precious mass I built up.

During that time I had muscle pain all the time and my mind was foggy. – Baptiste – PersonalFit  trainer

Also when doing that you are messing up your whole body balance by increasing blood acidity. Your kidneys are receiving a huge load of stress due to the ketones residues (toxic) to be drained out and eliminated. Therefore, most of the mass you lose is finally water.


What went wrong?

Your muscles are storing energy in glycogen, produced from the metabolization of carbohydrates.

Once those reserves are depleted, a hormone is released, the glucagon, responsible for the destruction of the  muscle mass to provide emergency energy to your body.

Fat does not provide energy fast enough, the Krebs cycle is slow! When energy is needed, body takes it where it is faster to get, in that case the amino acids in your muscles.



Carbs are useful, to protect your muscles, provide energy to the most important parts of your body and must be taken according to your activity level.

No carbs, no muscles. No muscles no energy consumption. No energy consumption, fat storage. These diets are drawing you into the famous vicious circle of diets making you lose 5kg to finally make you gain 10kg harder to remove.


A tailor made BALANCED diet and a fair amount of exercise is the path to go, ask your trainer, he/she could help with that *wink*

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