Carb cycling is a dietary tool that essentially uses a fasted and fed approach; however it is unique in that it focuses specifically on carbohydrate intake and not any other macronutrient.
It uses long periods of carbohydrate restriction coupled with short windows of carbohydrate referring (aka refeeds).
The theory behind this diet is similar to other diets that manipulate dietary carbohydrates in that they are attempting to leverage insulin signaling to maximize fat loss.
Carb cycling adopts a different approach from other diets like the ketogenic diet or other low carbohydrate diets by including periods of high carbohydrate intake.
Carb cycling is also referred to as the cyclic ketogenic diet as it uses periods of ketosis which are purported to have some health benefits.
History of Carb Cycling
From what we can gather carb cycling as it is currently thought of is believed to have been created and implemented by Franco Carlotto in the late 1980s or early 1990s. It was a riff off of both the high carbohydrate diet ideas that pervaded the bodybuilding scene and the low-carb diets that were beginning to gain popularity in some of the dieting circles.
It was the first attempt to blend several ideas into one diet that might take advantage of the benefits of different dietary approaches that were being implemented during the Golden Era of Bodybuilding. More recently, it has, for all intents and purposes, been repackaged into the modern day Carb Nite and Carb Backloading diets.
General Overview of Components and Main Principles of Carb Cycling
Carb cycling (AKA the cyclic ketogenic diet) typically prescribes 5-6 days of very low carbohydrate intake, usually less than 50 grams per day. On the 6th or 7th day there is a carbohydrate refeed day where carbohydrate intake increases up to 450-600 grams of carbohydrates while keeping fat intake incredibly low.
The goal of the refeed is to refill muscle glycogen levels, “recover” some potential down regulation of hormones that are affected during dieting, and carbohydrate restriction (e.g. thyroid hormone), and to help with mental aspect of restricting food to a substantial degree.
These refeed periods are critical aspects of the diet and are what set it apart both in practice and in theory from the ketogenic diet. They are designed to allow for periods of being well nourished from a carbohydrate perspective in order to allow for several days of high-intensity, high-volume training.
In practice, this makes a much better approach to cutting, or periods of fat loss, for individuals with high training volume.
As canonically thought of, carb cycling does not prescribe rigid timing or frequency of meals. Some variations of carb cycling, such as Carb Nite or Carb Backloading suggest defined windows of consuming your daily carbohydrates, specifically in the evening.
These aspects of carb cycling have not been tested or proven in the scientific literature and currently remain “bro-lore”.
Carb cycling restricts the macronutrients (aka the quantity) of your diet quite extensively but not the quality. For 5-6 days a week one is required to keep their carbohydrate intake incredibly low, usually less than 50 grams per day. On the 6th or 7th day one is required to eat 450-600 grams of carbohydrates and keep fat intake quite low.
As carb cycling is usually a “macro-based” diet, it is often layered on top of an If It Fits Your Macros or Flexible Dieting paradigm. As such, carb cycling is typically not restrictive of food quality and does not generally prescribe lists of “do not eat” foods.
Does it Include Phases?
Carb cycling essentially includes two phases:
- The low carb phase
- The refeed phase.
The phases can differ person to person based on their individual situation. For some individuals, their low-carb/refeed day ratio looks like 5:1 or 6:1, whereas other individuals with higher training volumes may opt for a 4:1 or 3:1 ratio.
Who is it Best Suited For?
Carb cycling is best suited for people who are trying to control calorie intake and enjoy a low-carb dieting approach, but who also want to be able to train at a higher level. Typically, ketogenic diets reduce an individual’s training capacity and recovery capacity.
Carb cycling allows for several day windows of high muscle glycogen levels to maximize training and recovery that are typically not available to individuals utilizing a ketogenic diet approach.
How Easy is it to Follow?
In many respects, carb cycling is the “easier to follow” version of the ketogenic diet. Carb cycling allows for a mental break from carbohydrate restriction and allows for days of higher calorie intake to also help curb some of the issues that arise during dieting.
Additionally, it does not have strict requirements of food quality and does not have a strict do not eat list. In other respects it can be difficult to follow as it requires large stretches of reducing dietary carbohydrate which can impinge on daily life and social gatherings.
The refeed days can be impractical and difficult to execute for some people as 450-600 grams of carbohydrates can be a lot of food to consume in one day.
Mainstream Belief Behind Diet
The main stream belief behind carb cycling is that it couples the theorized fat loss benefits of the ketogenic diet along with the benefits of higher carbohydrate intake for training and growing muscle. It is the attempt to merge the benefits of both low-carb and high carb diets.
While much of the “theory” underlying the diet has not been well researched in the science circles (aka no peer reviewed studies directly addressing carb cycling), it has been well used and well tested in bodybuilding, fat loss, weight lifting, powerlifting, and endurance circles.
Scientific Studies and Interpretation of the Data
A thorough review of medical science databases show no research studies to adequately address the proposed fat loss, health, or muscle building benefits of carb cycling.
However, it is likely that many of the benefits of the ketogenic diet, such as spontaneous caloric restriction, are present in carb cycling.
Much more research on this specific dietary modality is needed.
Carbohydrate cycling is a more practical way to implement some of the most effective principles of the ketogenic diet in a hard training, real-work population.
It allows for long stretches of caloric restriction via elimination of carbohydrate rich foods while also allowing for several days of hard training and can prevent the sustained reductions in muscle glycogen storage that arise from long-term ketogenic diets.
This diet can be a successful tool for bodybuilders or figure competitors who need to lose body fat while still have several high quality training sessions per week.
Can someone help me please , I'm 1m69 58kg
Struggling about what should I target , knowing that I have a very small low belly , should I work to loose it or focusing on gaining muscles , its more about should I be in a calorie deficit ? Please help
If you don't have much fat to lose, then I would suggest focusing more on building muscle. Any health issues I should know before recommending a program?
can someone help me with weight loss i am 15 years 187cm(6'2) 120kg
Hi, Eamchheng. Any health issues or restrictions that I should know about before we get going?
Plz help me with my carb plan 5 foot 6 140 lbs
Please, I need assistance to start my Carb cycle plan,
Weight(153kg), Height (6ft7inch)
Hi Saute- this article serves as a starting point to learn more about carb cycling. For more information on how to apply carb cycling based on your individual needs, check out the article here: https://www.muscleandstrength.com/articles/carb-cycling-build-muscle-los...
My height is 5 fit 4inch but my weight is 52 so I want to fast gain my weight please suggest the perfect supplymen
Plz help me,my weight is 78,height 5ft7inch.i want to shredded body...Plz help me
I wanna start my gain.
My current weight is 74kg .
Want to start my muscle mass gain. With moderate or less fat deposition ..
Kindly assist me.
And also what supplement n diet plan I should follow
Please, I need assistance to start my Carb cycle plan,
I'm 183 Cms, 81 Kgs, 15% Bodyfat, training 5 days per week
my main carbs source are Oats, Rice, Pasta, sweet potato, potato, and bread.
my main Protein source is: Chicken, meat, and fish
my main Fats source is Olive oil, nuts, Egg yolk
1st day 150g carb
2nd day 100g carb
3rd day 50g carb
4th day 125g carb
5th day 200g carb
Rest day lower than 50g carb
And your protein intake at least 1.5 * bodyweight
Fats from 10g to 25g allocate them based on the High, moderate and low carb days
I am going to be doing a 10 week heavy weight training program and want to carb cycle along side it. Does anyone know if this would be a good combo? Need to lose fat and want to get bigger and stronger. Also what supps are good to use when carb cycling?
Can you suggest a meal plan for a 15 year old girl 5'2 and looking to loose body fat I'm at 26% and i want to be 18%
Where do I find a good meal plan to carb cycle? I'm also not sure where my calorie level needs to be thanks
I am 5 feet 116 and 22% bf. I think I understand that for 5 days of the week I eat keto...so mostly fat macros, some protein and very little carbs...on high carb how do I figure the ratios for carb/p/f...what is the percent shakedown of each
from my opinion keto is not good for athletics u will lose your strength bro