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Ketogenic Diet And Endurance Performance

Training, Fitness, Power, Endurance

Is it advantageous to eat a diet that is high in fat and low in carbohydrates if one intends to participate in a triathlon?

Proper dieting is a key element of having success as an endurance athlete, but it is not feasible to formulate a nutrition plan that caters to every individual’s needs.

Some firmly believe that a ketogenic diet can enhance endurance. Here, we look into the why and the how…

Low Carb Diets and Endurance Performance

An athlete’s diet can be modified to help enhance their performance, including through the consumption of food and additional nutrients. A tactic that has been demonstrated to work for some long-distance runners is to consume a high amount of fat and a low amount of carbs, which is commonly referred to as the ketogenic diet.

Ketogenic Diet

The primary energy for the body comes from carbohydrates, which is transformed into glucose. Without carbohydrates, the body alters by changing fat into ketones that are made in the liver, which are employed as a substitute source of energy.

Ketosis is the term used to describe the process, and to get used to it, fats must constitute around 80% of the person’s diet, while carboyhydrate intake needs to remain under 50g per day (which is about the same as two slices of bread).

When taking part in endurance sports such as running or biking, the body mostly relies on carbohydrates as an energy source over a prolonged period of activity.

Glycogen exists in muscle tissue (300g) and the liver (90g), and has the capability to provide up to 1,600 calories of energy.

During an extended activity, these resources become used up, so competitors must continually consume carbohydrates during competition to sustain their energy levels.

One kilogram of fat holds approximately 7,700 calories of energy in its reserves. This means that a great deal of energy is produced, which explains why the ketogenic diet is so attractive to athletes who are performing endurance activities.

Utilizing this energy supply could cut down the requirement to top up fuel during exercising. Counting on fat may also lessen the chance of digestion issues experienced by some competitors when they consume large quantities of carbs.

Some have proposed that the ketogenic diet could diminish the amount of lactic acid that builds up in the body after engaging in physical activity, thus boosting recovery.

Ketogenic Diet Helps Improve Body Composition

It is said that there are advantages to following a ketogenic diet, including a change in physical form. The ability of an athlete to generate power relative to their weight is thought to be an indicator of their abilities, particularly when discussing cyclists.

This indicates how much force a sportsperson can generate in comparison to their body weight. Put differently, the greater strength athletes possess relative to their body mass, the quicker they will be.

One way to better this proportion is to shed some pounds, but that presents the danger of diminishing muscle mass, which makes the issue more serious. A study published in Metabolism looked at a cohort of endurance athletes who all followed the same exercise program for 12 weeks.

The group was separated into two sections, one that ate a ketogenic diet and the other that ate a high carbohydrate diet. Research revealed that those on a ketogenic diet lost 5.9 kilograms over a period of 12 weeks, while those on a high carb diet only experienced a 0.8 kilogram decline in weight.

It was determined that both groups kept their lean body mass. It was noted that there were enhancements in the ability to burn fat, which is one of the very few investigations to demonstrate progress in certain performance results.

Ketogenic Diet Helps Improve Performance

Studies indicate that the ketogenic diet yields higher fat burning levels than those resulting from a diet high in carbohydrates when considered in terms of maximum oxygen uptake.

VO2 max is an essential index of an athlete’s accomplishment and shows the maximum quantity of oxygen that can be utilized by them during physical activity. Fat burning rates attain their highest amount during moderate intensity exercise, which is equivalent to 59-64% of the VO2 max of highly trained endurance athletes.

Investigations have suggested that adhering to the ketogenic diet elevates fat-burning rates beyond what is usually attained with maximal oxygen uptake. Research indicates that athletes who are exercising to 70% of their VO2max have an increased ability to burn fat.

Fat burning is not as reliable an indicant of progress as increases in VO2 max, race times and time trials.

Despite the studies done, there is not yet sufficient evidence to show that the ketogenic diet enhances athletic ability. It is still evident that a diet high in carbohydrates can be advantageous in achieving better results in performance.

Ketogenic Diets and Performance Paradoxes

Fat Adaptation

It is thought that the difference in findings is chiefly a result of the insufficient timeframe to enable complete adaption to full fat. Many experiments have observed that people struggle to reach maximum performance for the first two weeks after beginning a keto lifestyle.

When we inspect the studies that showed a detrimental impact on performance, it is noticeable that some only took a brief amount of time to conduct, including ones with a duration of only 5 days.

Some of the research projects have gone on for a bit longer, for example. It usually takes three weeks, but research has proven it can take as long as 6-8 weeks for people to get accustomed to the ketogenic diet. There are also some authors who say it could take up to a year for someone to fully adapt to the diet.

This implies that the studies demonstrating the unfavorable impacts might not have given enough time for the process of fat adjustment to be completely completed.

The FASTER research project sought to find out the specifics of fat adapted substrate use in trained elite runners.

They analyzed the metabolic variances between marathon runners and triathletes who habitually ate either a low or high carbohydrate diet.

It was essential for this research that everyone involved had been on the same dietary regimen for a period of at least 6 months. After assessing the data, the majority of the participants had been abiding by their diet for around 20 months.

The findings demonstrated that on average, the amount of fat burned during peak activity was twice or three times more in the group that had a lower intake of carbohydrates than in the group that had a larger consumption of carbohydrates.

An intriguing point was that there was an identical pattern of muscle glycogen diminishment and reconstruction, which shows that the low-carb group had the capacity to uphold ‘usual’ glycogen amounts notwithstanding of reduced carbs.

Athletes demonstrated no major difference in their performance between the two groups. This research underscores the significance of the environment and application of the ketogenic diet in long-distance athletic performance.

It appears that making sure you have been following the diet plan for at least six months could be a crucial factor in achieving the best possible results.


Though individuals consuming a ketogenic diet do not necessitate carbohydrates or should they adhere to a carbo-loading diet, there are certain sports that involve strength-speed-endurance (such as sprinting or HIIT) which sometimes require promptly available glycogen levels in their muscles.

Individuals engaging in high intensity endurance activities such as HIIT workouts might find it advantageous to consume a larger portion of carbs ahead of time.

Take note that the type or standard of carbohydrates ingested is significant. It would be advisable to go with unprocessed, low glycemic index carbohydrates like yams or root vegetables.

Electrolyte Supplementation

Different problems have been brought up related to performance during the commencement of the ketogenic diet, particularly the levels and supplementation of electrolytes.

The keto flu is a widely recognized consequence of a low carbohydrate/ketogenic diet. This is the result of an unequal distribution of potassium and sodium in the body’s electrolyte levels.

Magnesium can be exhausted, especially during the early period of a low carb diet. Insufficient levels of magnesium can lead to excessive tightening of the muscles, causing cramping and agony which can worsen after physical activity.

Keeping the right amounts of potassium and sodium in endurance sports enables people to sustain their reserves in circulation (which lets the arteries widen during exercise at lower intensity) and balance their nitrogen while preserving the tissue’s function.

An easy way to rebalance electrolyte levels is to consume an isotonic sports beverage. Make sure to stay away from store-bought sports drinks and make your own organic alternative.

Protein Levels

The amount of protein you should have when you are following a ketogenic diet may differ depending on why you are on this diet in the first place. The amount of protein that is consumed can significantly affect an athlete’s performance if they do not have the right balance of it.

In order to maintain optimal physical performance and conserve lean body mass, it has been discovered that the necessary daily intake is between 1.2 and 1.7 grams per kilogram of lean body mass.

This quantity of protein may seem exorbitant compared to different kinds of ketogenic diets; however, when it comes to physical activity, more protein is essential and inadequate consumption can cause the athlete to lose muscle mass.

In a research study, athletes on a ketogenic diet who consumed 1 gram of protein per kilogram of their body weight per day saw a sizable decrease in their VO2 max after 3 months, while those who took in 1.5 grams per kilogram per day were able to hold their VO2 max.

Keto for Endurance Step-By-Step

If you are thinking of trialing this dietary approach into your training program for endurance performance, then it would be good to keep these steps in mind:

1. You Are Not New to Exercise

Before beginning a ketogenic diet, make sure your body is accustomed to the exercise or physical activity you plan to pursue. Learning about how to incorporate physical activity into a keto diet.

2. You Are Keto Adapted

Make sure to give your body a full 6 months to get accustomed to this new diet before participating in any sort of competition if you are aiming to improve your performance. Do not begin this diet less than two weeks prior to any important occasion.

3. Supplement Properly

Supplement properly and if needed (for guidance on foods that are high in potassium and sodium and how to supplement properly follow these links):

4. Ensure Sufficient Protein

Figure out what your perfect protein intake is – different types of ketogenic eating plans vary, particularly in regard to protein consumption. Ensure that you consume at least 1-1.2g of protein per kilogram of body weight each day.

5. Listen to Your Body

Setting up a ketogenic diet that is appropriate for you is the most essential factor. Taking a focused keto or oscillating keto eating regimen may very well be the superior options for you.

The Downsides of Following the Ketogenic Diet

Although there are many positives to the ketogenic diet, it requires drastic alterations to one’s eating habits which can be difficult to sustain.

This eating plan focuses on fatty items such as beef, chicken, dairy, eggs, cream, avocados, oils, nuts, and various kinds of seeds. No carbohydrate-containing foods are to be consumed, which includes grains, cereals, and starchy vegetables like potatoes. Also, all legumes including beans, lentils, and other pulses are to be avoided.

Vegetables usually just mean leafy greens and salads, and when it comes to fruits, only small amounts of berries are allowed.

Athletes on this specific diet may benefit from taking Elite All Blacks Gold Multivitamin, which contains essential vitamins and minerals, every day.

Making food that adheres to the keto diet necessitates careful organization and preparation which may be difficult for some sportspeople. Some people may dislike the continual consumption of foods that are high in fat and calories.

Eating too much protein can quickly throw you out of ketosis, so adherents must be extremely careful with their diet.

The keto diet should be a high-fat plan, not one that is high in protein. It is important to be mindful of not eating too much meat, poultry, and fish, because ingesting a large amount of protein with no carbohydrates can turn into sugar in the body.

When athletes start to use the ketosis diet, they could experience a lack in energy which could affect their practice and performance. The study indicates that it takes 3-4 weeks for complete adjustment to occur, which is essential to bear in mind.

Periodized Nutrition as a Low Carbohydrate Approach

Athletes may be able to use periodized nutrition to assist in making changes that result in an improved ability to exercise. The technique of ‘training low’ is used to control the amount of carbohydrates consumed in order to achieve desired improvements.

This is when you work out with a limited amount of carbohydrates accessible, yet it isn’t similar to ketosis as it is a short-term reduction of carbohydrates done intermittently.

The goal of training low is to create alterations that will encourage a higher fat burning rate, which will help conserve glycogen supplies for when the difficult, fast pace of a race is needed.

It is believed that consuming this type of food may help to strengthen the mitochondria which are the cells that generate energy in the body. AMPK is an important type of protein that is involved in muscle growth and apparently increases in concentration when there is a lack of glycogen.

Training with low intensity appears to be beneficial for achieving the same body changes that would happen with endurance training. Several methods have been proposed, which include:

  • Twice-a-day training sessions that withhold carbohydrate intake between workouts
  • Overnight fasting
  • Prolonged training and restricting or postponing carbohydrate intake during sessions
  • Delaying carbohydrate intake during recovery

You could incorporate this method in your workout regimen, beginning by doing it once a week. It is most beneficial to practice at an intensity level that is not too hard, so that you can gain back your strength before doing intense workouts.

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