What is Carb Cycling?

There's no shortage of different dieting methods for managing our weight. Diets in the 80’s focused on low fat, and then in the 90’s, it shifted to low carbohydrates (carbs).

So what now? The focus on carbs hasn’t gone away, but it has gone through some changes. Throughout the last two decades, there's been more focus on not only the amount of carbs … but the quality of those carbs.

Not all carbs are created equal, and some carbs are actually GOOD for you. I’m not talking about the processed breads, cookies, snack foods, and sugary drinks.
I’m talking about carbohydrates like fruits, vegetables, and whole grains. These carbs help give your body the fiber, vitamins, and minerals that other carbs can't.

One thing we've learned in that time though is ... carbohydrates are our body's primary energy source.

Knowing that, one approach to better use this energy is by including them when we need them ... and cutting them back when we don't.

This strategy is best known as carb cycling. If you’ve never heard of this method before, let me break it down for you!

In this article, we will discuss the in’s and out’s of carb cycling, and everything you need to know to use this technique for yourself!

What is Carb Cycling?

Carb cycling is a strategy used to help maximize fat loss by alternating between the number of carbs you take in a day.

How to Lose Body Fat

A simple way to do this would be to alternate between a “high-carb” day and a “low-carb” day. The number of “high” or “low” carb days can depend on your goals and your workouts for each day.

I am no stranger to this method. Back in my days of natural bodybuilding, I would alternate between high, moderate and low-carb days. It would all depend on if I had a strenuous workout or an easier cardio day planned.

Leg day, for example, is the perfect day for a higher carb day, since your body is using more carbohydrates for energy during those workouts. Doing so can tremendously help performance throughout the workout. It gives you the energy to push harder, for longer ... ultimately burning more overall calories and getting more out of your session. Low-carb days would be for low-intensity days like rest days or cardio. That's because your body doesn't utilize the same amount of energy on these days.

There isn’t a set amount of days you should be doing higher carb or lower carb days. You can customize your carb cycle around your training needs.

But Why Carbs?

Protein and fats are essential to our health. We need a certain amount of fats to maintain our proper hormone balance, absorb fat soluble vitamins, and help protect our vital organs. Too little fat intake for too long can cause some serious issues ... as a woman, you could lose your menstrual cycle. In men, it can lower testosterone [1].

Too little dietary protein can also have negative effects. You can lose muscle mass, become anemic, or just have a hard time absorbing specific nutrients.
So that leaves carbohydrates, our bodies main fuel source.

When you exercise at moderate to higher intensities, your body uses carbohydrates in the form of glucose for energy. Glucose that we don’t use right away is stored as glycogen in your muscles and liver. With the help of insulin, that excess glycogen in the liver can be converted into fat and stored in body fat cells.

So really, in many cases, altering your carbohydrate intake makes the most sense. Especially in order to increase insulin sensitivity, lose body fat, and improve performance [2, 3].

My Approach to Carb Cycling

In order to carb cycle correctly, you have to commit to tracking your foods. Knowing the exact amount of carbs, protein, and fats you need is super important for the planning required. Here's how I do it (and I track all of this through the 1st Phorm App)...

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First, start with how many calories your body needs. If you want to lose weight, multiply your current weight by 10-12. Maintaining? Multiply by 14-16. Want to gain weight? Multiply by 20-22.

Next, set your protein needs. Getting an adequate amount of protein will be important regardless of your specific goal. That's because protein will help your body preserve muscle and increase calorie burning. This can ultimately help boost your metabolism as you burn body fat or gain muscle mass [4].

The amount of protein you need during a carb cycle will remain the same. I recommend to keep your protein at 1 gram per pound of your goal body weight. So if you want to weigh 160 pounds ... you should have 160 grams of protein a day.

Multiply your goal weight by 4 to get the amount of calories coming from protein. Subtract this amount from your total amount of calories. The remaining calories can be split between carbs and fats.

When doing the math, keep in mind that 1 gram of carbohydrates = 4 calories ... 1 gram of protein = 4 calories as well ... and 1 gram of fat = 9 calories. The percentages of carbs and fats in relation to your overall calories can vary.

In fact, there's no set amount of carbohydrates that can be considered "low-carb". It's all relative to your overall goals. Generally speaking though, 100-125 grams of carbs would be considered low. That amount would also allow for an adequate amount of fiber.

When you alternate between high- and low-carb days, fiber should still remain constant. For women, that’s 21-25 grams per day, and for men it's 30-38 grams. Fiber helps stabilize your blood sugar and is essential for healthy digestion. So keeping fiber in the equation is super important.

High-carb days are much different. On these days, you can increase your carbs anywhere between 50-150 grams. If you're going by percentages, I recommend greater than 45% of your daily calories.

Here’s an example of a carb cycle schedule for a woman (like myself) while alternating low- and high-carb days based on workout intensity.

Day 1: high-intensity workout — 175-225 grams of carbs
Day 2: light-intensity workout — 100-125 grams of carbs
Day 3: high-intensity workout — 175-225 grams of carbs
Day 4: light-intensity workout — 100-125 grams of carbs
Day 5: high-intensity workout — 175-225 grams of carbs
Day 6: Light-intensity workout — 100-125 grams of carbs
Day 7: Rest day — 100-125 grams of carbs

Now, this is just an example. A lot of trial and error goes into the specific amount of carbs that would work best for you. These numbers all depend on your body type, your goals, and how active you are.

Something else that women should consider is their menstrual cycle. During weeks 2 and 3, women produce more estrogen and can utilize carbs more efficiently. So during these times, high-carb days may vary.

Carb cycling definitely has its benefits for performance goals and fat loss. But, we always recommend consulting your physician before trying any new diet.

Carb cycling is certainly discouraged in a lot of scenarios such as if you're pregnant, underweight, or have adrenal issues.

All that said, carb cycling, when done correctly, can be a great way to see results. Just know that there are a ton of different ways to go about carb cycling.

If you need help setting up a schedule for carb cycling (and I definitely recommend it) ... download the 1st Phorm App! Inside the app you can work 1 on 1 with a Certified Personal Trainer (NASM-CPT), Certified Nutrition Coach (NASM-CNC), or even one of our dietitians up at 1st Phorm HQ in St. Louis, Missouri!

We'll help make sure you're well equipped to see the best possible results with carb cycling.

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[1] Whittaker J, Wu K. Low-fat diets and testosterone in men: Systematic review and meta-analysis of intervention studies. J Steroid Biochem Mol Biol. 2021 Jun;210:105878. doi: 10.1016/j.jsbmb.2021.105878. Epub 2021 Mar 16. PMID: 33741447.

[2] Gower BA, Goss AM. A lower-carbohydrate, higher-fat diet reduces abdominal and intermuscular fat and increases insulin sensitivity in adults at risk of type 2 diabetes. J Nutr. 2015 Jan;145(1):177S-83S. doi: 10.3945/jn.114.195065. Epub 2014 Dec 3. PMID: 25527677; PMCID: PMC4264021.

[3] Escobar KA, Morales J, Vandusseldorp TA. The Effect of a Moderately Low and High Carbohydrate Intake on Crossfit Performance. Int J Exerc Sci. 2016 Oct 1;9(3):460-470. PMID: 27766133; PMCID: PMC5065325.

[4] Layman DK, Boileau RA, Erickson DJ, Painter JE, Shiue H, Sather C, Christou DD. A reduced ratio of dietary carbohydrate to protein improves body composition and blood lipid profiles during weight loss in adult women. J Nutr. 2003 Feb;133(2):411-7. doi: 10.1093/jn/133.2.411. PMID: 12566476.