What is the cyclical ketogenic diet (CKD)?
If you’ve read the resources in this blog and other websites, you’re probably pretty comfortable by now on what standard ketogenic diet (SKD) is. Carbs are restricted to individual tolerance (somewhere between 0 and 30g of carbohydrates a day). Protein is moderate, and you eat fat to satiety. Straightforward stuff.
There is another way of doing it that we’ve not really discussed before. An approach that offers a slightly different perspective…
What is the cyclical ketogenic diet (CKD)?
CKD cycles the standard ketogenic diet approach with short periods of higher carb, and less fat. Protein usually stays the same. These periods are usually 1-2 days, and tend to be taken over the weekend (convenient eh?).
The theory here is that the addition of a couple of carb-loading days restores glycogen in the liver and the muscles to support intense exercise across the carb-reduced days. So when you attack these high intensity workouts, your muscles have the energy to respond instantly – without waiting on the body to convert protein to carbohydrates. If you’re about to deadlift a load of plates each side of an olympic bar, your muscles need that energy immediately and often in great amounts.
Much like a standard ketogenic diet, there’s a tonne of ways to do it. We’re going to talk about a couple of the different methods here, which to choose if you fancy giving it a go and a few things to watch out for.
Who is CKD for?
The CKD originated out of the bodybuilding world as a hack to build size and muscle growth. Bodybuilders are the original bio-hackers and have never been afraid to experiment with foods or supplements to get the gains! It was found by those experimenting with a ketogenic diet that if they cycled in a couple of days of high carbs they got better results.
Because of the fact the cycle is about managing the process of glycogen depletion through carb restriction and intense exercise and glycogen restoration through carb-loading, this approach isn’t for anyone. It’s an approach that should only be considered by those are are undertaking exercise at intensity at least 4 times a week. This can be intense cardio such as HIIT (High Intensity Interval Training) or heavy strength and conditioning training.
It definitely isn’t for those using a ketogenic diet for therapeutic reasons. If you’re keto to manage some kind of condition – STEP AWAY FROM THIS ARTICLE NOW! Go and make yourself a kale smoothie or something.
If you’re just doing a little bit on the treadmill, or more into long distance running, the CKD is probably a square peg in a round hole. Your body will create additional glucose for energy through gluconeogenesis (the process that converts protein to carbohydrates).
How to do a CKD diet
The transition phase
You can’t just go straight in and get on board a CKD. Because of the fact you’re going to be dipping in and out of ketosis, it’s imperative that your ketosis pathways have been firmly established. This can only be really be done through getting fully keto adapted. The only real way to do that is to follow a strict standard ketogenic diet (SKD) for a minimum of 3 months first. This is important as it will firmly establish these important ketosis pathways for your body and mean your body should find it easier to get into ketosis when you get into the swing of cycling every week.
This is the time to trim down that fat and load up on those carbs.
How you actually go about carb loading depends on your motivations. If you’re purely about getting muscle size, definition and strength. It’s probably not worth thinking too much about what you eat. Eat like you’re on Death Row!
If you’re interested in longevity, healthspan and making sure your markers all stay in a nice range, you’ll want to consider a couple of things:
- Nutrient density and nutrient diversity – we recommend just switching to a higher carb paleo-based diet with a good blend of fructose and glucose. Fruits, potatoes, sweet potatoes are all good. If you get really into programming, you can look at some vitamins and minerals that you don’t get much of during the week when you’re eating keto.
- Sources of fat: try to stick with the same Omega 3, unrefined oils you use on a SKD. You need to optimise your Omega 6 to Omega 3 balance!
On the Sunday evening, don’t eat anything after 6pm.
Low Carb phase
When you begin the 5 day low carb phase, you need to kick things off with a bang. Get a pre-food workout in at as high an intensity as you can tolerate (HIIT or interval sprints are great). You want to be entering ketosis as soon as possible and working out on a fasted state is a great way to accelerate this.
Most people would skip breakfast this first day. Some will go further than that and kick off with a 24 hour fast – going through to 6pm that evening (you can play around with this range to figure out your ketosis threshold).
You need to make sure you get plenty of fats in. Your hormone response will be a little bit all over the place, so try to stick to 3/4 standard meals and quit snacking. Get the fats in to keep off any hunger pangs and make your ketosis phase tolerable. Your body is likely to be feeling the love for the carbs – so you need to stay disciplined. Otherwise you may end up derailing completely from your keto journey.
Across the 5 days, you need to be getting in a minimum four workouts at high intensity – whether that’s HIIT or heavy lifting. Make sure you are structured in your exercise plan across the 5 days to give all muscles a good workout, working towards that glycogen depletion across the entire body as the end goal. I think it’s good practice to go full body on the Friday to make sure you’re properly finished off! You must deplete those glycogen stores for this to be a viable option.
What about protein?
There should be no reason to play around with the protein amounts during this period. As you’re working out during the week, then recovering at the weekend, you’re going to need protein throughout. This will be at higher levels than someone who doesn’t move around with intensity. The actual amount will depend on your gender, height and ideal body weight. The Doc Muscles calculator is a good starting point.
CKD and the future
There are so many more studies we need to see in the world of keto. We know the long-term safety of a standard keto diet and some of the health benefits, not only of important health markers, but also in protection and fight against a number of conditions.
While we’ve had a good stab at answering ‘what is the cyclical ketogenic diet’, we don’t know at this stage what is optimum in the long term – SKD or CKD? I think if you approach a CKD sticking to whole foods throughout the entire process and ultimately cycling between keto and paleo is a sensible approach. This will give people far more intelligent than me at fancy sounding academic institutions time to figure all the science out. At least then, you’ll be eating a blend of nutritious foods loaded with goodness for your body. That can only ever be a good thing right?