Exercise and following the Ketogenic diet are considered by many to be two of the healthiest and most effective ways to rev up your metabolism, burn fat, and improve your overall health.
So what happens when you combine them?
You can probably guess that there’s a powerful synergistic eﬀect; many people report that when they combined Keto with the right exercise program, it marked a turning point in their health journey. The science is starting to support these reports.
For example, this recent study compared low-carb ultra-endurance athletes to athletes on a more traditional diet. During a three-hour-long run, the runners who consumed low carb for around 20 months burned 2-3 times more fat than those who followed a high-carb diet.
But the story isn’t always quite that simple.
When you drastically reduce carbs and enter ketosis, it causes a cascade of changes throughout the body’s various systems, and some of these impact exercise.
Depending on your health and fitness goals, you may need to either modify your exercise regime or consider a modified version of the Keto diet.
To help, we’ve put together this guide to help you navigate the (sometimes complex) relationship between exercise and ketosis.
In this guide, you’ll learn how to make the most of your experience with exercise and Keto. We’ll debunk misconceptions, help you to avoid pitfalls and maximize your performance in the gym, and guide you through choosing an exercise program that’s right for your personal health goals.
Best Exercises for Weight Loss
An exercise program that combines weight training, LISS (Low Intensity, Steady State), and HIIT (High Intensity Interval Training) is typically the most impactful for weight loss.
Weight training increases dense, lean muscle mass, which is often lost during periods of caloric restriction. In addition, that increased muscle mass helps you to work harder and move faster during aerobic training, which leads to an increased amount of fat and calories burned.
LISS is a specific form of aerobic exercise that pushes you just hard enough to rev up your metabolism, but at a low enough intensity that you can maintain a workout for 60 minutes or more, maximizing calories burned.
HIIT is a form of anaerobic exercise involving intense cardio in short bursts of 10 to 60 seconds that increases the body’s resting metabolic rate, meaning that regular HIIT sessions help you to burn more fat even when you’re at rest.
Note: Weight training may temporarily result in an increase in “scale weight”, due to the increase in muscle mass. When this occurs, it’s better to judge your body recomposition progress by inches and how your clothes fit.
Weight Training: When using weight training for weight loss, combine low reps/high weight (for muscle mass) with high reps/ lower weight (for muscle endurance) to maximize the advantages of each.
With low reps/high weight, use enough weight to feel muscle fatigue by 5-10 reps. With high reps and lower weight, lower the weight just enough that you can do 15-20 reps before muscle fatigue sets in.
For maximum impact in a short workout, focus on exercises that utilize numerous muscles at once, such as squats, bench presses, and deadlifts.
If you’re not sure how to do these exercises, we’ve got you covered! You’ll find tutorials and videos in the “Exercise” section of the Carb Manager app.
An additional benefit of combining weight training with Keto is an improved hormonal profile. At least one study indicates that Keto may increase testosterone in males, which could contribute to faster gains in muscle mass and fat loss when combined with weight training.
LISS: This style of workout is meant to maximize calories burned, and typically entails spending 30 to 60 minutes in the “fat-
burning zone” of roughly 70-80 percent of maximal heart-rate eﬀort. While the research is mixed, advocates of LISS maintain that it helps to kick-start weight loss, increase blood flow, and promote oxygen delivery within cells.
To calculate your fat-burning zone, subtract your age from 220. With the number you get, multiply it by .7 and .8 to get your heart rate range.
Example for a 40 year old: 220 - 40 = 180 x .7 = 136. This is the lower end of the range. Then 220 - 40 = 180 x .8 = 144 provides the upper end of the range. So the “fat-burning zone” heart rate range for a 40-year-old would be between 136 to 144
Some examples of LISS are running, fast walking, cycling, cardio machines, and swimming.
As a bonus, there’s some evidence that Keto may increase your LISS endurance and performance.
HIIT: This style of workout involves interval training in short, intense bursts of 10 to 60 seconds. Examples might include
sprints, pushups, sit-ups, lunges, jumping rope, burpees, or similar exercises. HIIT often includes both cardio and strength training to create a well-rounded workout.
Proponents claim that HIIT is unique among exercise programs in that it revs up the body’s metabolic rate and ability to burn fat while at rest.
A variety of preliminary research, including this meta-analysis from the British Journal of Sports Medicine, may support these claims, although further research is needed.
How to Maintain Peak Performance on Keto
It’s possible for some individuals following a Ketogenic diet to experience decreased performance with high-intensity anaerobic workouts. This is because muscles rely on glycogen (which is derived from carbs) to function during activities that involve high energy in short bursts.
Examples of these types of exercises are:
- Lifting weights to failure or close to failure
- Sprinting, cycling, or swimming at full speed for more than 10 seconds
- Playing sports that have minimal rest breaks such as soccer, rugby, and lacrosse.
- HIIT, Crossfit, or circuit training
Individuals may see the same type of decreased performance in other exercises, simply due to their individual body makeup and genetics.
This decrease in performance doesn’t typically aﬀect the fat burning and body recomposition impact of those exercises.
Keto dieters who experience a decrease in performance can often remedy the issue and get back to their baseline performance levels by switching to a modified Keto diet.
The two common styles of modified Keto diet are:
Targeted Ketogenic Diet (TKD): This version of Keto has users consume a meal with 20-50 grams of net carbs 30-60 minutes prior to exercise. This provides a targeted boost of carbs to feed muscles and increase glycogen stores for the upcoming activity.
Cyclical Ketogenic Diet (CKD) AKA Carb Cycling: This style of KETO involves consuming a low-carb keto diet for 5-6 days, and a higher- carb, low fat diet for 1-2 days. This method tops up muscle glycogen stores each week, while allowing the user to remain in deep ketosis the remainder of the week.
The results obtained from these methods are fairly equivalent.
Choose the method that makes the most sense for your personal schedule and dietary preferences.
Setting up Carb Manager for a Modified Keto Diet
Carb Manager Premium users can take advantage of our “Carb Cycling” feature to configure the app for the Cyclical Ketogenic Diet. This feature lets you set diﬀerent macros and diet goals for diﬀerent days.
This feature can be configured from the “Macros” tab found in settings.
Under the sliders, go to the “Everyday” drop-down to choose the days of the week when you want to set up carb cycling. By default, it will automatically say “Everyday,” but you can change it to specific days.
When you’re finished making your goals changes, be sure to tap “Apply” to save all changes.
Note that if you’re setting individual goals for diﬀerent days, instead of the everyday option, you’ll need to tap “select” after you set your goals for one day, then choose the next day, set diﬀerent goals, tap “select”, and so on. Repeat as needed for each day that you’d like to configure.
For the Targeted Ketogenic Diet, both free and Premium Carb Manager users can configure a simplified TKD regime. To do so, navigate to Settings, choose the Macros tab, then select either “custom grams” or “custom %” and configure a higher number of target daily macros.
Premium users can get a bit more granular in their TKD configuration.
For those who only exercise on certain days of the week, you can use the same Carb Cycling feature mentioned above to set a higher macros target for exercise days, while remaining at the normal 5% carb macros target on non-exercise days.
Tips for Exercising on Keto
#1 - Always listen to your body.
The first couple of weeks on Keto can be tough as your body adapts to using fat as its primary fuel source. Don’t feel bad about taking it easy during this adjustment period. If your body is telling you to temporarily reduce the intensity of workouts, it’s best to listen.
You may also notice reduced performance, even in exercises that don’t make heavy use of glycogen stores. This eﬀect is usually temporary. Once you’ve become fat-adapted, your physical performance will likely return to baseline.
#2 - Set a daily calorie goal.
While there’s more to body recomposition than “Calories-In/Calories- Out” (CICO), daily calorie intake still matters. Follow these steps to set a calorie goal in the Carb Manager app. If your goal is weight loss, select a caloric deficit. For users aiming to bulk up and minimize body fat, opt for a caloric surplus.
#3 - Connect a fitness device.
Consider using a FitBit, Garmin, or Apple Health device for more precise data on calories burned.
Carb Manager Premium users can also connect and sync their fitness device with the Carb Manager app.
# 4 - Eat enough protein.
Be sure to provide your muscles with the raw material they need to get stronger by maintaining protein at about 25% of total calories, or 0.8-1.0 grams per kilogram of your total body weight.
If you’re looking to gain significant muscle, consider consuming closer to 1.6 grams of protein per kilogram of body weight. But don’t go overboard. Research suggests that protein consumption beyond 1.6g/kg of body weight per day doesn’t yield additional benefits.
#5 - Get plenty of rest.
Your body needs deep rest in order to recover eﬀectively in between workouts. Be sure to take days oﬀ from exercise, and to take it easy and get plenty of sleep on those oﬀ days so that your body can recover and build optimal amounts of muscle tissue.
#6 - Configure your Carb Manager account settings to meet your needs.
If everything is going well, you may want to enable the “Deduct Calories When I Exercise” and “Deduct Macros When I Exercise” settings in the Carb Manager app to make things easier for yourself. For faster results or to push past a plateau, disable these settings. Click here to learn more.
# 7 - Drink plenty of water.
As we’ve mentioned elsewhere, it’s important to increase water intake when following a Keto diet to prevent dehydration and electrolyte imbalances. This becomes doubly important when adding exercise to the mix. Optionally, you can also track water intake via the Carb Manager app.
# 8 - Maintain electrolyte levels.
Similar to point #7 above, this is important enough with Keto on its own, but becomes even more crucial when combining exercise with Keto. You can top up electrolyte levels by consuming adequate amounts of green leafy vegetables, such as kale, spinach, and collard greens, and by adding pink Himalayan sea salt to your food and water. Optionally, you can also take a high-quality commercial electrolyte supplement.
Putting it All Together
While the Ketogenic diet may get a “bad rap” in certain athletic circles when it comes to performance, it can be easily modified to maintain performance levels found with carb consumption while providing all of the benefits of ketosis.
In fact, one of the most powerful aspects of Keto is its adaptability. Just as Keto can be tweaked and modified to suit vegetarians, vegans, or those following Kosher or Halal, it can easily be tweaked for exercise-based performance.
Studies suggest that ketosis has powerful fat-burning and weight-loss properties on its own. When paired with your favorite workout, it becomes a powerhouse combination that may help you to attain your long term health and fitness goals.
If you're not already, be sure to log food and exercise, track weight loss, get motivation from our community, and much more!
When you’re ready, take advantage of Carb Manager Premium’s powerful features to support your fitness journey, including support for Carb Cycling and CKD, fitness device integrations, meal plans, premium recipes, and much more.