Despite how it is often referred to in discussion, the keto diet is not a single diet. “Keto diet” is an umbrella term for a variety of diets that aim to induce keto-adaptation of your body. There are actually a number of different types of “keto diet.”
Today, we’ll discuss a few key types of ketogenic diet, how they work, how they differ, and how they compare to one another. This is important if you’re thinking of trying out a ketogenic diet but want more guidance than the typical “eat less carbs and more fats”!
We’ll outline four key types of ketogenic, or fat-metabolizing, diets that are each aimed at different populations. These four types are:
- Standard Ketogenic Diet (SKD)
- Cyclical Ketogenic Diet (CKD)
- Targeted Ketogenic Diet (TKD)
- Intermittent Energy and Carbohydrate Restriction (IECR)
These each have their own quirks and differences, so you’ll find plenty of variety to choose from and hopefully a diet that will meet the specific needs you’re looking to hit.
Standard Ketogenic Diet
This is the most well-known version of what a keto diet is. The SKD is simply a diet that focuses on reducing carbohydrate intake to below 30g per day, with moderate protein intake and a focus on dietary fats.
The standard ketogenic diet doesn’t have a set of approved timings, foods, or other structures. It simply states that you should reduce your carb intake and rely on fats. What those fats are is not outlined, though we do believe that a simple 2:1 ratio of unsaturated to saturated fats is another key factor.
This approach to keto is probably the most difficult to drop straight into and should be approached gradually. The freedom to eat a wide variety of foods without a strict schedule is one of the best ways to get adjusted to the keto diet and find which foods, habits, and processes help you best stick with the diet. It should be noted, however, that the risk of keto flu can be higher if you’re entirely restricting carbs.
The standard ketogenic diet is also the most effective option for inducing a state of keto-adaptation. It is both the strictest on carb intake and the least prescriptive of all the diets on this list.
In one sense, it is restrictive by reducing carb intake, but it is very freeing in terms of the food, exercise, and timing of meals. This makes for a very sustainable diet, but the challenges associated with it can still be significant if you’re going carb “cold turkey” or if you want to perform strength and power exercise at high intensity.
The Effects of a Standard Ketogenic Diet: Benefits and Challenges
The traditional or standard approach to keto dieting is the most effective since it almost totally eliminates carbohydrates from the diet and triples down on the use of fats as a fuel-source. While other diet variants on this list will strategically recruit carbohydrates for performance, this total reduction means high-level optimization for keto-adaptation.
The downside to this is that the standard ketogenic diet can easily become inappropriate for athletes in mixed-system sports. These are sports that require a combination of endurance and power. Reducing carbs makes this a very difficult process, so the standard keto diet is a bad idea for most athletes, outside of those specifically focused on endurance.
This means that the adaptation process, particularly, can be a rough time. This makes the standard approach to the keto diet more effective for the recreational exerciser or endurance athlete, rather than athletes in mixed sports or those focusing on performance in strength or power. Other types of keto diet will probably be more effective for this, as we’ll discuss later.
Making the Most of a Standard Ketogenic Diet
This diet variant starts with a gradual taper down from a “normal” diet to a low-carb high-fat one. Going cold turkey on carbs is an easy way to run into some of the negative symptoms of keto dieting known as Keto flu. A smart choice is to slowly approach the diet by reducing carb intake over a period of 2-4 weeks.
Remember that the point of a ketogenic diet for the average person is based around your health. Staying healthy/avoiding symptoms is a big part of this pursuit. There’s no health benefit to accepting a severe case of keto flu, and patience is a key player in getting the most from a standard keto diet.
This approach to keto dieting will also need a little more focus on the things you’re missing out for exercise performance. Electrolyte supplementation is more important on a keto diet (from a dedicated supplement or sea salt), especially when it comes to magnesium. Being diligent with these key nutrients supplementation is crucial.
Cyclical Ketogenic Diet
This is a diet aimed at reducing the negatives of the standard ketogenic diet and providing a solid mid-ground between a “normal” mixed diet and a ketogenic diet, while reaping the majority of the benefits from the latter.
The simplest way of looking at cyclical keto dieting is that there are “carb re-feed” days and low-carb days. These are common practices for bodybuilders and other athletes that need to burn through fat while keeping energy stores high on specific days.
The idea is a simple one: don’t eat carbs except for during the one or two carb re-feed days that fall just before or just after particularly-tough workouts. This approach is often referred to as carb cycling and has a long history with bodybuilders, even if it hasn’t been well-understood in the past.
This is obviously quite different from the traditional ketogenic diet. It focuses on athletes and their needs while also balancing out some of the regular nutritional needs. This makes a lot of sense, since the idea for reducing carbs is to improve fat-metabolism, but there’s no reason to never eat carbs (especially since carbs are essential for healthy fat metabolism).
Keto-adaptation isn’t the only goal of this diet, but it does improve things like insulin sensitivity and the efficiency of fat-metabolism for fuel. These obviously won’t compare to a strict ketogenic diet, but this also comes with the fact that cyclical ketogenic dieting is not strict: it allows for periods of re-feed that can also be useful for enjoying rare, luxury foods.
Benefits and Challenges
The use of carbs in a cyclical ketogenic diet comes with the obvious benefit of being more effective in high-intensity strength and power exercise. This is the kind of benefit that we look for when training in mixed sports like soccer and rugby – sports that require a high level of endurance but benefit from bursts of power.
Re-feeding before a match or weight training session is a great method for athletes who need to train with serious intensity but also need to improve their endurance capacity. This is definitely the kind of diet that makes sense for mixed athletes, as it allows for stamina gains without inhibiting them overly much during power training.
The problem with carb cycling, however, is that it’s still far from optimal for anyone concerned with their physique. It can be used as an effective diet for cutting down body fat – much like the standard ketogenic diet – but they are both directly opposed to building muscle.
The ketogenic diet directly ramps up production of AMPK. This is a compound in the body that signals for a lack of energy, which directly shuts down the muscle-building signals in the body. This makes cyclical ketogenic dieting too strict on carb intake for athletes like bodybuilders and strength athletes since it inhibits recovery and growth.
There are alternatives (which we’ll discuss further below), but a more flexible approach to carb-feeding and carb-restriction will be necessary for those looking to build muscle. This is especially the case if you’re trying to build muscle and burn fat at the same time, which requires a carefully-managed diet and hormonal system.
This diet variant will, however, provide a great way of tapering into the standard ketogenic diet or any other. It is a step in the direction of reducing carbs that will fend off some of the worst symptoms of the keto flu – like reduced exercise performance, fatigue, and migraines – while still allowing you to improve your fat-metabolism.
This is a great stepping stone into the ketogenic diet or a great middle ground if you’re not looking for the extreme carb restriction of the full keto experience. When re-feeding, it’s important to choose a balance of carb sources and consume them with sufficient protein, as these variables make or break your re-feed’s effectiveness!
Who Should Use the Cyclical Ketogenic Diet?
This is pretty self-explanatory: anyone who is tapering into a full ketogenic diet or athletes in a sport that combines strength training with high endurance demands. The timing of a re-feed allows you to be mostly prepared for any type of challenge on a day’s notice.
This type of diet is also a great way to cut down weight rapidly while still maintaining some performance and health characteristics. While it won't be as effective for sparing/building muscle due to the prolonged periods of AMPK-boosting carb restriction, it can increase the ability to burn fat when using the right amount and type of exercise.
For the average joe who has a stone of body fat or more to trim down in order to look and feel better, this diet has a lot of benefits. It’s a great entryway to the ketogenic diet family without dive-bombing performance in the gym. It also brings lots of benefits to the first-timer with diet and exercise because they won’t notice the performance decreases associated with carb-depletion.
If you’re experienced and looking to cut weight while gaining muscle, this probably isn’t the diet for you. It leans more toward weight loss, rather than muscle sparing or building. So if your goal is cutting down rapidly, it might be a great choice for you.
Targeted Ketogenic Diet
Targeted ketogenic dieting is one of the most effective and nuanced approaches to keto, and we are strong advocates for this type of dieting/training.
The idea of a targeted ketogenic diet is simple: carbohydrates are exercise fuel and should be consumed at a time – and in an amount – that fuels your exercise and nothing else. This means a carbohydrate feed pre-workout and possibly post-workout but a low-carb diet at all other times.
This type of dieting works beautifully because periods of ketosis allow for improved insulin sensitivity and fat loss, while carb feeding immediately pre and post workout improves performance and helps to ward off deficiencies and common keto flu symptoms.
Carbohydrates are a rapidly-absorbing form of energy – especially if you have increased insulin sensitivity from a ketogenic diet. This means that the carbs you eat before a workout will be used to provide energy for that workout and be used up by the time you’re done. This means that the effect on ketosis of pre-workout carbohydrates is relatively small, but workouts are much better.
This is another attempt to balance out ketogenic dieting with your muscle, strength, and power needs. The extra carbs fuel intense high-force exercise like heavy lifting and sprinting and allows for reduced AMPK-signaling and improved recovery, all while continuing the benefits of a ketogenic diet. It’s still a concern, but carb feeding is a daily process rather than a rare luxury.
These aren’t perfect solutions, of course. You’ll still not build muscle at an optimal rate and your workouts may not feel as good as they did on a high-carb diet. However, it has a better likelihood of improving long-term exercise performance and muscle-sparing effects than a cyclical diet, as you won’t be carb-restricted for several days at a time.
As before, this is a matter of balancing your desire to maintain performance against the speed at which you want to lose weight. The Targeted Ketogenic Diet may be slower to burn fat, but it provides a greater performance function than a standard ketogenic diet. Make sure you’re performing strength and power exercises before endurance when on this diet!
Benefits and Challenges
The obvious benefit of this type of diet is improved workouts and the sparing of muscle during a weight-loss diet. This is a great balance, as a standard keto diet poses problems for both of these. Training becomes labored while muscle wasting is a bigger challenge during a calorie restriction.
This means that you can continue effective workouts and minimize the performance-compromising effects of a tough diet. Again, this is perfect for the mixed athlete, but this type of cutting diet can also be used by those in power – but not muscle – sports. Power and strength can stay high, but ketogenic dieting is clearly not the choice for physique athletes.
This makes the targeted ketogenic diet even better than the cyclical diet for the average joe who wants to cut weight but still experience the benefits of consistently progressing (or at least maintaining) performance in the gym.
One relevant challenge is that this makes endurance exercise slightly less effective and even less important. While other forms of the ketogenic diet rely on being in a state of exercise-induced ketosis for fat-burning, this diet attempts to avoid the worst effects by adding pre-workout carbohydrates.
Keto-adaptation is more important than ketosis for this, however: you don’t need to remain in ketosis to experience fat-efficiency. You only need to have been in ketosis consistently enough to become more effective when your body is forced to draw on fats for fuel.
The targeted ketogenic diet favors power, strength, and high-intensity interval training over long-form endurance workouts. You don’t need to be running marathons to make the most of a targeted ketogenic diet, though endurance enthusiasts are often considered to be the main focus group for the keto diet.
Who Should Try TKD?
This is the first ketogenic diet that we genuinely recommend as a general diet as it doesn’t specify a goal. While other forms of keto may be aimed at endurance, targeted ketogenic dieting is appropriate for the vast majority of people who are looking to lose weight and keep muscle and performance.
The muscle-sparing effects of targeted carb restriction and feeding are a great way to fend off the health effects of keto flu while also making some moderate gains in the metabolism of fats as fuel. The consumption of high-GI carbs before training makes this an easy diet to maintain and an effective one for a mixture of strength and HIIT exercise.
It’s still not optimal for those who are concerned with muscle gains. It’s a cutting diet and still falls prey to a milder version of the muscle-inhibiting processes mentioned in relation to other keto diets. However, it’s far milder, and you probably won’t see drastic changes to your performance while your weight drops.
We believe this is the best choice for an athlete in a mixed sport who is looking to cut weight, manage their health, keep performance up, and also improve overall endurance. CrossFit athletes can benefit from a targeted ketogenic diet, as can wrestlers and other mixed-demand athletes. This is also great for anyone who is in a mixed sport or is training for general health and fitness.
The versatility of this type of ketogenic diet, and the fact that it’s based on the science surrounding carbohydrate metabolism, is one of our favorite aspects of the targeted ketogenic diet. If you’re trying to reduce keto flu risks and keto-adapt slowly into the full-fledged standard keto diet, then this method can be a great gateway.
IECR: A Keto Option for the Average Joe?
It’s hard to say whether the IECR diet – intermediate carbohydrate and energy restriction – is really a fasting diet or a ketogenic diet. It lands itself somewhere in-between the two and only reduces total carb intake 2 days a week – so it might not even be a proper keto diet to most people.
However, during those 2 days, the science shows an improvement in the metabolism of fats and a reduction in diabetes risks/symptoms. This is combined with the mild health effects conferred by being at a calorie restriction at least some of the time. It sounds like a fad, but the science appears pretty solid.
The idea is to eat a “normal” diet – one that includes a scientific mix of macronutrients – from Monday to Friday. During the weekends (or any other 2-day period), you drop your caloric intake to around 65% and drop carb intake to 30g per day or less, with a focus on high-protein, nutrient-dense, high-fiber dieting for these two days.
This is a way of increasing insulin sensitivity without compromising your normal day-to-day training or bringing on the intense AMPK problems found during the standard ketogenic dieting. It provides some of the benefits with seemingly none of the real problems associated with long-term ketosis.
While this is still not a muscle-building diet, it is the most well-rounded and easily maintained. It provides a great way to balance your overall intake of carbs with the benefits of a ketogenic diet in a way that is relatively easy to achieve and doesn’t overly restrict your food choices. It’s the ketogenic diet for 2 days a week, and allows you to slowly achieve improved fat-metabolism.
This method is a viable option because of the two main roles it plays. First, it is the easiest way to ease into the ketogenic diet because of how little time you spend without carb intake. Four weeks of this keto diet variant can be a great way to introduce yourself to the habits and adaptations of ketogenic dieting. Second, it can be used most effectively for those with diabetes risks or a desire to stay strong and muscular during the cutting process.
We’re also inclined to believe that this is the best type of carb restriction for those looking to alter the composition of their body: you can lose fat and gain muscle at the same time with proper pacing and management of carb intake. This can be combined with IECR to get the most from your diet, thus combining the health and endurance benefits of carb restriction with proper carb feeding.
An IECR diet with a 0.7% bodyweight reduction per week is the upper limit for this process, which makes for a slow, consistent change to your body that will show up in your conditioning and your strength/musculature!
Finding what works for you
Ultimately, the most effective type of ketogenic diet for you is the one that best suits your goals and needs.
The goals you set for yourself can be anything from “looking and feeling better” to “performing at the highest level in my sport”. These are both entirely valid, but they determine both the kind of diet that you should be on and how you should train. An endurance athlete should focus on a standard keto diet, as it fits the typical lifestyle and training for those sports while including no real drawbacks from their carb restriction.
Simply, the more strength and power you need for your training – and the more muscle you’re looking to build – the less you can restrict your carbohydrates. Carbs are key to the muscle-building processes and recovery from intense exercise. You need to balance how much weight you’d like to lose against how important performance is to you.
Performance and weight loss are competing goals on a sliding scale when it comes to these ketogenic diets. IECR leans towards power and muscle, while a standard keto diet lean towards maximum fat loss and endurance. Having a firm idea of where you fit on this continuum is key for maximizing your results.
How Bad do you Want It?
This is another key factor in your choice of diet: how important are your goals to you, and how strict do you want to be with yourself?
Ketogenic dieting can be a great choice for those who find fats to be their favorite food group, while it can be awful (but transformative) for those with carb dependency. For competitive athletes, there’s no “if” – you do what you need to do to be the best at your sport. However, for most people, a keto diet is a case of give and take. How much dietary freedom or results do you want?
Do you want to restrict your carbs to 30g per day, every day, and never eat any sugary foods? You might be fine with this, but for others, it’s a bridge too far. Especially when you consider the fact that IECR and targeted ketogenic diets offer a way of still enjoying those sweet foods in support of exercise without guilt, albeit with limited quantities.
Closing Remarks
While you’ll always need to be sensible about your food choices, sometimes the diet you choose is the result of the foods you want to eat. A diet that is too strict can be unsustainable, and so this can be a serious part of picking the right diet.
Standard, cyclical, and targeted ketogenic diets are all different in their restrictions and benefits. Find the one that has the best carryover to your goals and the diet you’re most likely to stick to. Consistency is the key to success in weight loss no matter what diet your choose to employ.
We’ve outlined the key differences between these keto diets, what the science says about them, and even highlighted how you can work ketogenic elements into a “normal” diet with IECR. At this point, all that’s left is for you to choose what suits you best and what benefits you want to prioritize.
With the information in this article, you’ve now got the knowledge you need to make those choices and weigh the benefits and sacrifices each diet requires of you. We can’t make that decision for you, but we’ve done our best to give you the tools to decide.
Now go hit it. You can do this.
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