Keto For Marathoners: Does It Help Or Hinder?

The keto diet is a popular topic among runners, especially those who are training for a marathon or ultramarathon. The diet involves eating very few carbohydrates and much higher amounts of fat, which means the body has to use fat as its primary fuel source instead of carbohydrates. This state is called ketosis, and it can take the body a while to adjust to this new way of fuelling itself.

Some elite runners have tried the keto diet with varying results. Zach Bitter, the 100-mile American record holder, is a notable example of a runner who performs well on a keto diet. He eats a diet that is less than 5% carbohydrates and has said that he noticed a drop in energy when he first started the diet, but eventually, it stabilised.

Other runners have reported a decrease in performance when trying the keto diet, and some have said that they never fully adjusted to the diet. It is also worth noting that the keto diet is not recommended by many coaches and sports nutritionists for runners.

So, can the keto diet help with marathon training? The answer is yes and no. The keto diet may work for some runners, but it is not guaranteed, and there may be a decrease in performance while the body adjusts to the new diet.

The basics of keto running

A keto diet is a low-carb, high-fat diet that aims to make your body more efficient at using fat as its primary energy source, as opposed to carbohydrates. By lowering your carbohydrate consumption to 5-10% of your total daily calories (or 25-35 grams of carbs a day), your body enters a "ketosis state," where it starts burning fat as fuel.

The keto diet is popular among runners, especially ultrarunners, as it can improve energy levels and aid weight loss. However, it is often looked down upon by coaches and sports nutritionists due to its potential negative impact on performance.

Transitioning to a keto diet can be challenging and may cause low energy levels and decreased athletic performance initially. It is recommended to start during the off-season, giving your body time to adjust. Gradually reduce your carbohydrate intake, and increase healthy fats such as avocado, nuts, butter, and olive oil.

It is important to consume enough protein to aid muscle recovery. Electrolytes are also crucial, as they are often obtained from carbohydrate-rich foods. You may need to take salt pills or drink bone broth to replenish electrolytes.

On race day, you may benefit from consuming small amounts of carbohydrates to boost your energy. However, be cautious as this can kick you out of ketosis. Some keto runners choose to carb-cycle, strategically increasing carb intake around long runs and challenging workouts.

Keto running can lead to improved fat adaptation, where your body becomes more efficient at burning fat for fuel. This can result in increased endurance and steady energy levels during long runs. Additionally, keto diets are associated with improved sleep and energy levels, fat loss, and potential wider health benefits such as improved heart and brain health.

The main drawback of keto running is the potential decrease in athletic performance, especially in high-intensity cardiovascular activities. It may take months to fully adapt to using fat as the primary fuel source, and even then, your anaerobic capability may be throttled.

The effectiveness of a keto diet for runners is highly individualised. While some runners thrive on a keto diet, others may struggle to adapt. It is important to do your research and consult with a healthcare professional before making any significant dietary changes.

How to get into ketosis

Before we get into how to get into ketosis, let's first understand what it is. Ketosis is a metabolic state in which, due to a lack of carbohydrates, the body uses fat as its primary source of energy instead of glucose. Ketosis occurs when the body starts producing ketones for energy (derived from fat) as opposed to glycogen, which mainly comes from carbohydrates.

• Reduce Carbohydrate Intake: Eating a very low-carb diet is the most important factor in entering ketosis. Reduce your carb consumption to 50 grams or less per day.
• Increase Healthy Fat Intake: Consume plenty of healthy fats such as fatty fish, olive oil, avocado oil, and avocados. A ketogenic diet calls for a high fat intake, typically 55-60% of calories from fat.
• Increase Physical Activity: Being more physically active can help you get into and stay in ketosis. Exercise helps deplete the body's glycogen stores, which encourages the body to turn to fat as a source of fuel.
• Intermittent Fasting: Intermittent fasting can help you get into ketosis by reducing the number of calories and carbohydrates you consume.
• Test Ketone Levels: Use ketone urine strips, a ketone breath meter, or a blood ketone meter to test your ketone levels and determine if you are in ketosis.
• Consume More MCT Oil: Medium-chain triglycerides (MCTs), found in MCT oil and coconut oil, can help increase ketone levels and are easily absorbed and converted into ketones by the liver.

Things to Keep in Mind

• Getting into ketosis can take a few days to a week or more, depending on your body and how strict you are with your diet and exercise routine.
• Ketosis can have some side effects, such as the "keto flu," which may include symptoms like headaches, fatigue, nausea, bad breath, and increased thirst.
• Long-term effects of ketogenic diets are not well studied, and there are potential risks such as nutritional deficiencies, kidney stones, changes in electrolyte levels, and bone loss. Always consult a healthcare professional before starting any new diet.

Keto and athletic performance

The ketogenic diet is a low-carb, high-fat diet that puts the body into a state of ketosis, where it uses ketones (derived from fat) as the main energy source instead of carbohydrates. This diet has been used to improve the health of people with diabetes and epilepsy, and more recently, it has been explored for its potential benefits in physical performance. While the traditional approach for exercise is to consume a high-carbohydrate diet, the ketogenic diet offers an alternative that may provide certain advantages for athletes, especially those engaging in endurance events. However, there are also some limitations and considerations to be aware of when adopting a ketogenic diet for athletic performance.

The Benefits of Keto for Athletes

Improved Fat Adaptation

Ketosis can lead to improved fat adaptation, where the body becomes more efficient at burning fat and ketones for fuel. This can be particularly beneficial for endurance athletes as it may help prevent "hitting the wall," which occurs when the body runs out of readily available glycogen from carbohydrate sources. By becoming fat-adapted, athletes can tap into their body's fat stores for energy, potentially extending their endurance capabilities.

Endurance Exercise and Ketosis

Ketosis may be advantageous for endurance exercises at lower intensities since fat provides more energy during these activities. Additionally, ketosis can help preserve muscle glycogen, which is crucial for endurance performance. However, it is important to note that fat utilization requires more oxygen compared to carbohydrate utilization, which may impact performance at higher intensities.

Muscle Growth and Ketosis

A ketogenic diet can aid in fat loss, which is essential for improving the ratio of fat to muscle, benefiting athletes looking to enhance their exercise performance or meet specific weight goals. Additionally, a ketogenic diet may help preserve muscle glycogen and teach the body to utilize fat more efficiently as a fuel source.

The Challenges of Keto for Athletes

Diminished Performance

One of the main challenges of the ketogenic diet for athletes is the potential decrease in athletic performance, especially at higher intensities. Carbohydrates are still the preferred fuel source for high-intensity exercises, and without sufficient carbohydrate intake, athletes may struggle to maintain their usual pace or power output.

Keto Adaptation Takes Time

Adapting to a ketogenic diet can take time, and the initial transition period may be challenging. During this period, individuals may experience low energy levels, decreased athletic performance, and other symptoms often referred to as the "keto flu." It is important to be prepared for these potential challenges and give the body time to adjust.

Social and Lifestyle Considerations

Adopting a ketogenic diet can impact social situations and daily life. It requires careful planning and monitoring of food choices, and it may be difficult to find suitable options when eating out or socializing with friends and family. Additionally, the restrictive nature of the diet may be challenging to maintain in the long term for some individuals.

Nutritional Considerations

A ketogenic diet requires a significant reduction in carbohydrate intake, which means that popular sports fuels like gels, sports drinks, and bananas may no longer be suitable. Athletes need to find alternative sources of fuel that fit within the ketogenic guidelines, which can be a learning curve.

The ketogenic diet has potential benefits for certain types of athletes, especially those engaging in endurance events. However, it is important to recognize that it may not be suitable for all athletes or all types of sports. Each individual's experience with the ketogenic diet may vary, and it is essential to consider the potential benefits and challenges before adopting this dietary approach. Additionally, working with a qualified nutritionist or sports dietitian can help ensure a safe and effective implementation of the ketogenic diet for athletic performance.

Pros and cons of keto for runners

The keto diet is a popular choice for many, but what about runners? The diet involves eating a lot of fats and very few carbohydrates, which goes against the grain of a typical runner's diet. So, what are the pros and cons of keto for runners?

Pros

• Fat adaptation: The keto diet can help runners become fat-adapted, meaning their body is using fat as its primary fuel source. This can be beneficial for long-distance runners, as it provides endless energy and can help prevent 'hitting the wall'.
• Improved sleep and energy levels: Once the initial transition period is over, keto can lead to improved day-to-day energy levels and better sleep.
• Weight loss: Keto can lead to fat burning and weight loss without losing muscle mass.
• Potential wider health benefits: Some studies suggest that keto may have anti-cancer effects and benefits for heart and brain health.
• No more gastric distress: A low-carb diet can prevent gastric distress during long-distance runs, as runners can perform for hours while consuming fewer calories.

Cons

• Diminished performance: Keto can negatively impact athletic performance, particularly for high-intensity running. Studies have shown a decline in running speed and power for athletes following a keto diet.
• Transition period: Getting into ketosis can take time and the initial transition period can be difficult, with side effects such as low energy, headaches, and cravings.
• Social impact: Following a keto diet can impact your social life, as it requires strict control over what you eat and may involve skipping social meals.
• No guaranteed endurance benefits: The research on keto for runners is limited and inconclusive, with some studies showing no improvement in endurance or performance.

In conclusion, while keto may have some potential benefits for long-distance runners, there are also drawbacks, particularly for high-intensity running. More research is needed to fully understand the effects of keto on running performance, and it is important for runners to carefully consider the pros and cons before making any dietary changes.

Keto marathon nutrition

The keto diet is a popular choice for those looking to improve their health and lose weight. But what about for marathon runners? Can the keto diet help improve their performance, or will it hold them back? In this article, we will explore the benefits and drawbacks of adopting a keto diet for marathon runners. We will also provide practical tips and advice for those interested in trying out the keto diet for their marathon training.

The keto diet, short for ketogenic, is a low-carb, high-fat diet that aims to make the body more efficient at using fat as its primary energy source instead of carbohydrates. Typically, the body relies on glucose from carbohydrates as its main fuel source. However, by drastically reducing carbohydrate intake and increasing fat intake, the keto diet forces the body to enter a state of ketosis, where it burns fat for fuel.

The simple answer is yes, it is possible to run a marathon while following a keto diet. However, there are some important considerations and potential challenges to be aware of. One of the main challenges is the adaptation period. When first transitioning to a keto diet, athletes often experience decreased energy levels and endurance performance. This is because the body is used to fuelling with carbohydrates and needs time to adjust to using fat as its primary fuel source. According to nutritionists, this adaptation process can take months.

It is important to note that some athletes may never fully adapt to fuelling for endurance training on a keto diet. In these cases, carb cycling or switching to a low-carb diet during higher mileage weeks may be more feasible options.

Practical Tips for Adopting the Keto Diet for Marathon Training

• Give yourself time to adapt: It can take weeks or even months to reach full ketosis, so it is recommended to make the transition during the off-season when training intensity and volume are lower.
• Increase electrolyte intake: Carbohydrate-rich foods tend to be high in sodium, so it is important to find alternative ways to get electrolytes, such as salt pills or bouillon cubes dissolved in water.
• Make your own snacks: Most commercial sports snacks are packed with simple sugars, which can kick you out of ketosis. Opt for keto-friendly snacks like frozen peanut butter balls, dark chocolate, and cheese sticks instead.
• Focus on protein for recovery: Consuming protein after runs helps rebuild muscle fibres. Try making your own protein shakes using whey or soy protein powder with keto-friendly almond or coconut milk.
• Stick to a consistent diet: Eating keto can be time-consuming as it requires preparing most meals from scratch. To save time, stick to a few go-to foods that work for you and keep them readily available.
• Eat a big breakfast: Breakfast is crucial when training for a marathon on a keto diet. Eat a large, fat-nutrient-dense breakfast to fuel your body for the rest of the day. If running in the morning causes cramps, consider having a small snack during your run and a big breakfast afterward.
• Expect low-energy days: Even with a consistent fuelling and recovery routine, low-energy days are normal during marathon training. Adjust your workouts on these days and focus on the bigger picture of your training plan.
• Limit interval training: Interval training can be more challenging on a keto diet due to the lack of quick-burning carbs. Keep interval workouts to a maximum of once a week and plan easier runs the day before.
• Strategically add carbs: Small amounts of carbs are okay on a keto diet, especially when planned around runs. Try adding a bar or sugar to your drink during interval workouts or taking a gel during long runs for an energy boost.
• Manage your expectations: Eating keto may negatively impact your speed and performance. Set realistic expectations and focus on the potential benefits of ketosis, such as increased stamina.

Adopting a keto diet for marathon training can be challenging but rewarding. It is important to give yourself time to adapt to the diet before your race and be mindful of the potential drawbacks. If you are interested in trying the keto diet for your marathon training, be sure to do your research, consult with a healthcare professional, and listen to your body.

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