Keto Workout Timing: When To Start Exercising?

The ketogenic diet is a popular, low-carb, high-fat diet that can lead to weight loss and improved health. While on the keto diet, the body enters a state of ketosis, burning fat for fuel instead of carbohydrates. This can have an impact on your workouts, as fat is not as easily burned as carbohydrates, and your body may take time to adjust to this new fuel source.

When starting the keto diet, it is normal to experience side effects such as brain fog, nausea, fatigue, and headaches, known as the keto flu. These side effects, along with the body's adjustment to using fat for fuel, can make working out feel more challenging, especially during the first few weeks of the diet. High-intensity workouts may become more difficult, as they require short bursts of energy that the body typically gets from carbohydrates.

However, low-intensity aerobic exercises, such as yoga, jogging, and cycling, may be easier on the body when on the keto diet, as they can be fuelled by fat. It is important to listen to your body and adjust your workouts accordingly when starting the keto diet.

You might not feel like working out at first

It is highly likely that you will not feel like working out when you first start the keto diet. This is due to the infamous "keto flu", which can cause you to feel foggy, nauseous, and fatigued during the first two to four weeks of the diet. You may also experience headaches during this time. These symptoms are caused by changes in your metabolism as your body adjusts to burning fat for energy, as well as by electrolyte dips due to the keto diet's tendency to flush water out of your body initially. As a result, you may find that working out feels like a chore, even if you are typically an active person.

Additionally, your body will feel extra sluggish during workouts due to the lack of readily available energy sources. On a typical diet, glucose and glycogen (sugar and carbs) are stored in the muscles for quick energy, but low-carb diets deplete these stores, leaving your body with only fat to burn, which is not as easily accessible. This means that even after the keto flu has passed, high-intensity workouts such as HIIT, sprinting, or weightlifting will still be more challenging, as they require quick bursts of energy. You may also find that you get tired during these workouts more quickly than usual and have less endurance.

To make the transition easier, it is recommended to stick to low-intensity aerobic exercises such as yoga, jogging, or biking when first starting the keto diet. These types of exercises will be easier on your body as it adjusts to using fat as its main energy source. It is also important to take it easy and not push yourself too hard during the first week or two of the diet. Instead of jumping straight into intense workouts, consider adjusting the weight or number of reps you typically do to build up your endurance.

The type of workout matters

The keto diet is not your typical diet. It restricts carbs, which are one of the fastest fuel sources that the body relies on. This means that your body will be running on fat for fuel instead of energy-boosting carbs. As a result, you may experience the infamous "keto flu" and feel foggy, nauseous, and fatigued during the first few weeks.

The type of workout you choose to do while on the keto diet is important because your body won't have the quick energy burst needed for high-intensity workouts. High-intensity workouts like HIIT, sprinting, or weightlifting require quick bursts of energy, which carbs typically provide. Even after the initial keto flu period, these types of workouts will still be more challenging, and you may get tired more quickly.

Low-intensity aerobic exercises, such as yoga, jogging, and biking, are better suited for the keto diet because they use fat as the main source of energy. These types of workouts will be easier on your body and can help you build up your endurance. It's important to take it easy at first and gradually increase the intensity and duration of your workouts.

While the keto diet may not be ideal for high-intensity workouts, it can lead to greater weight loss by preserving lean muscle mass. Additionally, studies have shown that keto diets coupled with moderate-intensity exercises can positively affect body composition and enhance the body's ability to burn fat.

If you're an athlete or someone who regularly engages in high-intensity workouts, you may want to consider a targeted or cyclical ketogenic diet. A targeted ketogenic diet involves consuming easily digestible carbs before a workout, while a cyclical ketogenic diet involves following the standard keto diet most of the week and having dedicated days for eating higher-carb meals to restore energy levels.

You might see more gains

While it may not feel great to work out on the keto diet, you might see more gains in lean body mass. A study in the Journal of Strength and Conditioning Research found that resistance training on the keto diet might lead to an increase in lean body mass. The study tracked 25 men following a resistance training program, with some on the keto diet and others on a traditional Western diet. While both groups gained lean body mass and lost body fat in the first 10 weeks, only the keto group showed more lean body mass gains after the final week.

The keto diet is designed to put the body in a state of ketosis, where it burns fat as a fuel source instead of carbohydrates. This can be beneficial for weight loss, as the body will burn more calories per day. However, it's important to note that burning fat doesn't always mean fat loss. To lose weight, you still need to burn more calories than you consume.

Additionally, the keto diet may not be the best choice for those looking to add muscle mass. The lower amounts of calories and protein consumed on keto can make it more challenging to build muscle. The body also has fewer carbohydrates available, which it would usually store in the muscles and use for muscle growth.

When it comes to exercise, the keto diet may impact your performance during high-intensity workouts. This is because high-intensity exercises rely on carbohydrates as a quick fuel source. With the keto diet, the body burns fat for energy, which is not as easily accessible, leading to a decrease in performance.

Low-intensity aerobic exercises, such as yoga, jogging, and biking, may be a better option while on the keto diet. These types of exercises use fat as the main source of energy, so you may find them easier to do. It's important to listen to your body and adjust your workouts accordingly when starting the keto diet.

You could try a targeted ketogenic diet

The targeted ketogenic diet (TKD) is a version of the standard ketogenic diet (SKD) with one important difference: when you eat carbs. On the SKD, you keep carbs low at all times. On a TKD, you consume your daily allotment of carbs before, during, or after a workout.

The TKD is meant to improve exercise performance for high-intensity workouts or extended bouts of activity. If you are sedentary or only do low-moderate intensity exercise, then the SKD is all you need.

The TKD can be a good option if you are a beginner or intermediate weightlifter, athlete, and/or training at high intensities regularly. It may provide you with the performance boost you need but are not getting from SKD alone.

By targeting carb intake around high-intensity exercise, you're providing your muscle cells with the fast-burning fuel essential for max (or near-max) effort activities lasting between 10 seconds and 2 minutes. Carbohydrates are essential because, after around 10 seconds of near-maximal to all-out effort, the muscles start to rely on glucose for energy by using a metabolic pathway called glycolysis.

What to eat on TKD

Most people experimenting with TKD find that 25-50g of carbohydrates taken 30 minutes prior to exercise gives them the best performance. It's recommended to eat simple, easily digestible carbs, such as liquids or high glycemic foods that absorb fast into the body—sweet tarts, white bread, candy bars, gummy bears, hard candies, Gatorade, Powerade, and natural maple syrup.

However, the best sources of carbs for a successful TKD would be dextrose and glucose. You want to avoid fructose, as it tends to go directly to the liver to replenish liver glycogen instead of going to the muscle, which is what we want.

Will TKD kick me out of ketosis?

With the influx of carbs that you will be taking in before exercise, your ketones levels will inevitably decrease. Many will find that they drop out of ketosis for a few hours after their workout, due to increased insulin levels. The good news is that working out will make various systemic changes that help you get back into ketosis.

If you want to boost your ketone levels naturally, you can do some low-intensity cardio to help lower insulin even more and increase the free fatty acids in your blood. Another strategy is to supplement with MCTs before, during, or after exercise. These fatty acids will be converted into ketones regardless of your insulin and blood sugar levels.

Should I implement a targeted keto diet?

If you are a beginner or intermediate weightlifter, athlete, and/or training at high intensities regularly, then you might want to try a TKD. Remember, the goal with a targeted keto approach is to get just enough carbs to provide glucose for the workout, allowing you to boost performance and build more lean muscle mass while keeping body fat down.

After you are keto-adapted, however, the extra carbs may not be helpful anymore. Studies show this can happen after around four weeks for athletes on a strict keto diet. For this reason, you may experience that the TKD doesn't do anything for you after you have been on the keto diet for 1-2 months and are keto-adapted. If this is the case, then you should stick with the SKD or try the Cyclical Ketogenic Diet (best for high-intensity athletes/exercisers).

You could also try keto cycling

Keto cycling, also known as the cyclic ketogenic diet (CKD), is a dietary approach that alternates between following a strict ketogenic diet and consuming higher amounts of carbohydrates. The purpose of keto cycling is to provide metabolic flexibility, make adhering to the keto diet easier in the long term, and ensure your body receives the benefits of carbs it needs.

Keto cycling alternates between following a strict keto diet and eating more carbs. Many people who adopt keto cycling follow a keto diet for five to six days and a higher-carb diet for the remaining one to two days per week. This method of dietary cycling allows you to experience the benefits of ketosis, such as fat loss and potentially improved metabolic health, while also reaping the benefits of consuming carbs.

How to Implement Keto Cycling

If you're considering trying keto cycling, here are some basic steps to follow:

• Start with a standard keto diet: Begin with a strict ketogenic diet for a few weeks to allow your body to adapt to burning fat for fuel instead of carbs. The level of carb restriction required to achieve ketosis can vary between individuals, but an example would be consuming 55% to 60% fat, 30% to 35% protein, and 5% to 10% carbohydrates.
• Design your cycling schedule: Transition to a keto cycling pattern once you feel like your body has adjusted to ketosis. A common approach is to follow the keto diet for five to six days, followed by one to two days of higher carb intake, though this can be adjusted based on your goals and preferences.
• Implement the keto phase: During the ketogenic phase, consume high-fat, moderate-protein, and very low-carbohydrate meals. Prioritize whole foods like avocados, nuts, seeds, fatty fish, eggs, and non-starchy vegetables such as spinach, broccoli, bell peppers, mushrooms, and cauliflower.
• Transition to your non-keto phase: During this phase, replenish your body's glycogen stores by consuming carbohydrates from healthy sources like fruits, whole grains, and starchy vegetables (e.g. potatoes, corn, and squash). Slightly reduce your fat intake to balance your calorie consumption.
• Adjust as needed: Remember that there is no one-size-fits-all approach to keto cycling. It's important to track your body's response and make adjustments as needed. Depending on your goals, you may want to monitor your weight, energy levels, and ketone levels using at-home urine tests to ensure you're effectively cycling in and out of ketosis.

Tips for Successful Keto Cycling

• Establish a schedule: Create a clear cycling schedule that suits your lifestyle, alternating between ketogenic and higher-carbohydrate days.
• Plan your meals: Develop a meal planning habit to ensure your meals align with the requirements of each cycling phase, emphasizing healthy and nutrient-dense foods overall.
• Track your macros: Depending on your goals, consider tracking your macronutrients (protein, carbs, and fat) to stay within your allotted carb limits. Stock up on snack foods that adhere to each cycling phase to avoid cravings that could derail your progress.
• Stay flexible: Be prepared to adjust your plan as needed. You may find that some aspects of your original plan don't work as expected.

Potential Benefits and Drawbacks

Keto cycling may be beneficial for individuals looking to lose weight, as it can help sustain weight loss by preventing a slowdown in metabolism and replenishing glycogen stores on higher-carb days. It may also be a good option for those interested in the keto diet but seeking more flexibility and an easier-to-maintain plan.

However, keto cycling also has potential drawbacks and challenges. Maintaining ketosis can be challenging, and regular fluctuations between high- and low-carb intake may lead to digestive issues. It requires planning and tracking of the ketogenic and carb cycling phases, and there is a risk of cardiovascular problems depending on saturated fat intake.

Additionally, it can be challenging to find a comfortable balance that doesn't lead to overindulging in refined carbs on higher-carb days, which can counteract the benefits of ketosis and make returning to a state of ketosis more difficult.

Who Should Avoid Keto Cycling?

Keto cycling is not suitable for everyone. People with diabetes, especially those requiring insulin therapy or blood sugar-lowering medications, should proceed with caution due to potential fluctuations in blood sugar levels. Individuals with type 1 diabetes or kidney problems should avoid the diet, along with anyone with conditions related to the pancreas, liver, thyroid, or gallbladder.

If you are pregnant or nursing, it is important to consult your primary care provider before starting keto cycling or any restrictive diet.

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