by Matt Weik, BS, CSCS, CPT, CSN
Many people have heard of, tried, or have considered trying the ketogenic diet. But very few people have heard of the cyclical ketogenic diet.
A ketogenic diet provides many clinically studied benefits, but it isn’t a one-size-fits-all solution. There are various ways to follow the keto diet based on your needs or preferences, and one option is the Cyclical Ketogenic Diet (CKD), also known as cyclical keto.
The cyclical keto diet, also known as carb cycling keto, might be ideal for hard-training athletes who need to replenish muscle glycogen stores. This method involves “cycling” between periods of very low-carb, high-fat intake and high-carb, low-fat intake.
Some research suggests that increasing your carb intake on certain days boosts muscle mass and athletic performance.
In this article, we will dive deeper and learn more about the cyclical ketogenic diet and its benefits so that you can make an informed decision on whether or not this is a nutrition plan you want to try for yourself.
Disclaimer: This article is for informational purposes only and is not meant to treat or diagnose any condition. It is recommended that you speak with your doctor before starting any exercise program, making changes to your nutrition plan, or adding any new supplements into your current regimen.
What is the Cyclical Ketogenic Diet?
Cyclical ketosis involves cycling in and out of a ketogenic state each week. Also known as carb cycling, this diet includes one to two days a week of higher carb consumption, with the remaining five to six days following a standard keto diet.
On the cyclical keto diet, you consume large amounts of quality fats and very few carbs (less than 50 grams of net carbs per day) for five to six days. Then, on the “carb refeed” day, you increase your carb intake to around 150 grams.
Full ketosis isn’t suitable for everyone. Incorporating clean carbs like sweet potatoes, squash, and white rice one day a week helps support the healthy functioning of body systems that require some carbohydrates.
Benefits of Cyclical Ketogenic Diet
Below are some of the benefits of the cyclical ketogenic diet:
1. It may help improve muscle growth
Anabolic hormones, such as insulin, are suppressed on very low-carb diets like keto. Insulin regulates muscle growth by transporting amino acids and glucose into muscle cells, boosting protein synthesis, and reducing protein breakdown.
The cyclical keto diet can strategically raise insulin levels on certain days, allowing you to leverage insulin’s anabolic effects to help improve muscle growth.
2. It may improve your workout
Working out on a keto diet is entirely possible and can even enhance ketosis while maintaining your fitness levels. You can engage in activities like cardio (running and cycling) and resistance training (lifting weights) without issue.
However, during longer workouts or exercises requiring short bursts of energy, such as HIIT, sprinting, and agility training, your body may experience energy dips. The muscles used in these explosive workouts can tire or fatigue easily.
Having more carbs in your diet can help sustain energy levels, allowing you to push harder and improve your performance during high-intensity activities.
3. It improves gut health
The cyclical ketogenic diet can also benefit your gut health. On low-carb days, you can consume plenty of gut-friendly butyric acid found in butter or ghee.
On high-carb days, specialized microbes in your gut can produce butyrate by fermenting dietary fiber from low-toxin vegetables.
The impact of dietary fiber on your health depends on your gut condition. Those with healthy guts may benefit from the fiber in foods like potatoes, mushrooms, or carrots.
However, individuals with leaky gut syndrome or IBS might fare better by avoiding fiber altogether.
4. It may improve an athlete’s performance
Refeeding with carbohydrates can benefit elite athletes on very low-carb diets. A study involving 29 elite racewalkers found that periodic high-carb intake improved performance.
The study showed that walkers who consumed high-carb meals before training sessions experienced significant performance improvements compared to those on a standard keto diet. The researchers concluded that athletes who periodically increased their carb intake saw enhanced performance, while those adhering strictly to a keto diet did not.
5. It makes keto easier
Restricting carbs on the keto diet can be challenging, especially when you see someone enjoying a fruit or chocolate. The cyclical ketogenic diet allows you to incorporate foods like apples (even several times a week), which can boost your will to continue the diet.
This flexibility can also help maintain long-term adherence to the keto diet. Having planned carb intake days to look forward to can make the diet more sustainable and enjoyable over time.
What Does the Science Say?
Research on the cyclical ketogenic diet is limited, but two 2017 studies offer insights into its benefits for athletes.
In one study, 25 men in their early 20s followed a ketogenic diet or a Western diet for ten weeks. After a week on the Western diet, the ketogenic group showed significant increases in lean body mass and power output on the Wingate Power Test, improvements not seen in the Western diet group.
Another study examined low-carb, high-carb, and periodized high-carb diets in elite race walkers. It found that strict low-carb diets could impair high-intensity performance. However, those on the periodized high-carb diet experienced notable performance improvements, supporting the benefits of cyclical carbohydrate refeeding for athletes.