Keto And Working Out: A Healthy Combination?

The ketogenic diet is a popular approach to weight loss and improved health, but it can be challenging to combine with exercise. The keto diet limits total carbohydrate intake, which can make high-intensity workouts more difficult as the body prefers to burn carbohydrates during vigorous exercise. However, it is still possible to work out on the keto diet, and there are several tips that can help optimize performance. These include timing your carbohydrate intake, progressing gradually with your workouts, staying hydrated, and considering keto breaks. While the keto diet may not enhance performance, it can increase weight loss from fat stores and improve endurance during exercise. It's important to listen to your body and make adjustments as needed.

High-intensity exercises may be tougher on keto

The keto diet is a low-carb, high-fat diet that puts your body in a state of ketosis, where it burns fat for fuel instead of carbohydrates. While this has weight-loss benefits, certain workouts, especially high-intensity exercises, may be more challenging.

High-intensity exercises, such as strength training, sprinting, and other sports, require short, intense bursts of energy. Typically, the human body powers through these activities by burning carbohydrates stored in muscle cells as muscle glycogen. However, on the keto diet, the body prioritizes burning fat for energy, which is not as easily accessible a fuel source. This results in a less efficient process, leading to limited performance during high-intensity workouts.

A study published in the Journal of Physiology supports this notion. It found that athletes on ketogenic diets burned more fat during training but experienced worse athletic performance than those on a standard diet. They also reported greater exertion to complete the same workouts and were less likely to finish them.

Additionally, transitioning to the keto diet can be challenging, with symptoms like exhaustion, lack of energy, and muscle cramping, often referred to as the "keto flu." Engaging in high-intensity exercises during this transition period could exacerbate these symptoms and make your keto journey more difficult.

Therefore, if you plan to combine the keto diet with high-intensity exercises, it is essential to proceed gradually and strategically. Timing your carbohydrate intake around your workouts, opting for strength training over HIIT, and ensuring adequate hydration and electrolyte intake are some recommended strategies to optimize your performance and make the process smoother.

Keto may boost fat burn

While the keto diet may not be the best option for those who engage in high-intensity exercises, it can be beneficial for boosting fat burn during low to moderate-intensity workouts.

The keto diet is designed to put the body in a state of ketosis, where it burns fat as fuel instead of carbohydrates. This shift in fuel source can lead to increased fat burning during certain types of exercises.

A study of elite competitive walkers found that those on ketogenic diets burned significantly more fat during training compared to those on a standard diet with carbohydrates. Similarly, a study in the Journal of Physiology found that athletes on the ketogenic diet burned more fat during training than those on a normal carb-rich diet.

Additionally, a 2018 study found that when overweight adults replaced carbohydrates with fat in their diet for five months, they burned approximately 250 more calories per day than those on a high-carb and low-fat diet. This increased calorie burn can contribute to weight loss, as long as there is an overall calorie deficit.

However, it is important to note that burning more fat during keto does not necessarily translate to losing more fat. While keto can be effective for training the body to use fat as fuel, it is still essential to maintain a calorie deficit to achieve fat loss and weight loss.

Furthermore, while keto may boost fat burn during certain exercises, it may not enhance performance. The competitive walkers in the study experienced worse athletic performance and felt that it took greater exertion to complete the same workouts as those on a standard diet.

Therefore, while keto may boost fat burn during low to moderate-intensity exercises, it may not be the best choice for those seeking to improve athletic performance, especially in high-intensity activities.

You may feel less energised at first

When starting the keto diet, you may experience a period of adjustment, often referred to as the "keto flu". This is when your body switches from burning glucose to burning ketones as its main fuel source. During this transition, your body may feel like it's running out of energy, and you may experience exhaustion, brain fog, muscle cramping, and irritability.

This period usually lasts for the first few days or weeks of the diet, and it's important to take things slow during this time. It's recommended to focus on lower-intensity workouts, such as walking, cycling, yoga, or light stretching, to help your body adjust without feeling too terrible.

The keto flu can also affect your mental clarity, so it's best to avoid workouts that require quick reactions, such as cycling on roads with cars or challenging outdoor hikes. It's also not the best time to try a new, intense workout class.

However, this sluggish feeling is only temporary, and once your body becomes ""keto-adapted", your energy levels will increase, and you'll be able to up the intensity of your workouts.

To help ease the symptoms of the keto flu, make sure to stay well-hydrated, as dehydration and electrolyte depletion are common side effects of the keto diet. You can also try taking MCT oil or MCT powder supplements, which provide a quick source of energy and may help improve your workouts.

Additionally, make sure you're eating enough, especially healthy fats. Keto is not a low-energy diet, and undereating can leave you feeling tired and hungry. Aim for a balanced intake of fat, protein, and carbohydrates, with most of your calories coming from healthy fat sources such as grass-fed meats, fish, avocado, and coconut oil.

Remember, the keto diet is an adjustment for your body, and it's normal to feel less energised at first. By taking things slow and listening to your body, you'll be able to optimise your workout routine and fully reap the benefits of the keto diet.

Your body may burn calories quicker

A 2018 study found that when overweight adults replaced carbohydrates in their diet with fat for a period of five months, their bodies were able to burn approximately 250 more calories per day than people who ate high-carbohydrate and low-fat diets. This is because the body is burning fat for fuel instead of carbohydrates.

However, it is important to remember that gram per gram, fat is more calorie-dense than carbohydrates: each gram of fat contains 9 calories, while a gram of protein or carbohydrate has 4 calories. Therefore, while your body may burn calories quicker, you will also be consuming more calories through fat.

To lose weight, your body still needs to be burning more calories overall than it is consuming. As Andy Galpin, PhD, a professor of kinesiology at California State University, notes, "calories are not the only thing that's relevant, but they still matter".

How to Burn Fat on the Keto Diet

Combining exercise with the keto diet will maximise the health benefits and weight loss benefits of the keto diet while still maintaining lean body mass. Exercise helps maintain blood sugar levels and improves insulin sensitivity, which increases the efficacy of the keto diet.

The ideal heart rate for fat-burning is 50-70% of your maximum heart rate. This is considered "moderate exercise". Vigorous exercise takes your heart rate up to between 70 and 85% of your maximum heart rate. While it is important for your cardiovascular health to reach this vigorous level from time to time, the 70% sweet spot will be the most optimal for your body when it is in a state of ketosis. That's because your body will be optimised to burn body fat.

To calculate your maximum heart rate, subtract your age from 220. For example, if you're 30 years old, your maximum heart rate will be 190 beats per minute (BPM). Your optimal heart rate for burning fat will be 70% of 190, or 133 BPM. Use a wrist monitor or chest monitor to help you stay in the zone while you're working out.

Types of Exercise to Burn Fat on the Keto Diet

Low- and medium-intensity cardio is one of the best activities for fat loss. This includes brisk walking, moderate cycling, and yoga. These types of exercises are also the least likely to be affected by the keto diet, as they do not require the same short bursts of energy that high-intensity exercises do.

However, it is still possible to do high-intensity interval training (HIIT) or CrossFit-type workouts on the keto diet, but you will need to adjust your macronutrients. If you keep the work intervals under 10 seconds and allow for a longer 3-minute rest between sets, you can make HIIT work for you without your performance suffering. Alternatively, you can have longer, 3-minute work sets and rests to get your body into an aerobic state.

Weight lifting is another important part of any fitness plan. It will help you build muscle mass and optimise your metabolism. The most efficient way to use weight lifting to your metabolic advantage is to choose exercises that engage large muscle groups, such as squats, lunges, overhead press, pull-ups, and bench press.

Keto is better for maintaining muscle mass

The keto diet is a low-carb, high-fat diet that encourages your body to use ketones as fuel instead of glucose, which is the body's preferred source of energy. While it is well known as a weight-loss diet, it also has benefits for muscle maintenance.

Research has shown that the keto diet can increase weight loss from fat stores without affecting lean muscle mass. A study in the *Journal of Physiology* found that athletes on the ketogenic diet burned significantly more fat during training compared to athletes on a normal carb-rich diet. This is because, when in a state of ketosis, the body uses fat as fuel instead of carbs, directly using fat for energy and accelerating weight loss.

A study of 25 college-aged men found that a traditional Western diet and the ketogenic diet were equally effective for muscle gain, strength, and performance. Other studies have shown that keto may provide similar strength and performance gains as a conventional high-carb diet while also helping shed body fat.

Tips for Maintaining Muscle Mass on Keto

• Ease into your workout routine: When starting the keto diet, your body goes through a metabolic adjustment phase, switching from burning glucose to burning ketones as its primary fuel source. This adjustment is called the keto flu and can last anywhere from one to three weeks. While working out can help ease these symptoms, your first few workouts might feel more challenging than usual. It's important to listen to your body and scale your workouts accordingly.
• Choose a keto-friendly pre-workout: Most pre-workout supplements are loaded with sugar, which can kick you out of ketosis. Pure C8 MCT oil is one of the best keto-friendly pre-workouts because it boosts energy and enhances metabolism, helping to increase efficiency while exercising on keto.
• Opt for strength training over HIIT workouts: The body uses fat as its primary energy source during lower-intensity aerobic workouts, and since the body is fat-adapted while in a state of ketosis, you’ll reap even more weight loss benefits. Anaerobic exercises like HIIT, CrossFit, and sprinting require large bursts of fuel from glycogen, which a low-carb and low-sugar keto diet isn’t suited for.
• Increase your fat intake: Your body relies primarily on fat for fuel when you limit carb intake and are in a state of ketosis. After accounting for protein and carbs, fat should make up the rest of your diet.
• Eat plenty of protein: Protein is the building block of muscles, so it's essential for maintaining muscle mass. Most studies suggest that eating 0.7–0.9 grams of protein per pound of body weight is ideal.
• Track your carb intake: To reach and stay in ketosis, most people need to eat fewer than 50 grams of carbs per day. Timing your carb intake around your workouts can be beneficial, as this strategy, known as a targeted keto diet, can aid exercise performance.
• Consider supplements: While not required, supplements may help you build muscle. If you’re struggling to reach your daily protein goals, you could use a protein powder supplement such as whey, casein, pea, or hemp protein. You could also try a creatine monohydrate supplement, as studies show that it can aid gym performance, leading to more muscle gain.
• Get plenty of sleep: Proper sleep is very important for muscle gain and exercise performance.

The keto diet can be an effective way to maintain muscle mass while also promoting weight loss and improving overall health. By following the above guidelines and listening to your body, you can optimize your results and maintain muscle mass while on the keto diet.

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