Can You Workout While Intermittent Fasting? Is It Safe?

Can You Workout While Intermittent Fasting? Is It Safe?
Cordelia Tan

Cordelia Tan | Author

Cordelia Tan, is a passionate advocate for women's health and well-being. Known as Fasty's number one fan, she expertly blends Eastern and Western health practices, offering a holistic approach to diet and wellness. Her work focuses on empowering women with knowledge and practical strategies for a healthier life.

Do you want to try intermittent fasting but don’t want to stop exercising? Or, it might be that you are already practicing intermittent fasting and want to maximize your results with exercise. Whatever the reason for combining intermittent fasting and exercise is, there is a question worth discussing. 

Is it good to work out while intermittent fasting? Let’s answer this and many other questions.

The Effect of Working Out During Intermittent Fasting 

Adhering to an intermittent fasting plan where you fast and eat during specific windows throughout the day brings much more than a mere daily structure. When you merge exercise and fasting, your body finds ways to give you the energy needed to function while promoting positive physiological processes. 

Exercising while fasting encourages:

Autophagy: the cellular process of destroying damaged cellular components and cells to generate new ones. 

Anti-aging: changes in metabolism can slow down natural aging processes and support longevity. 

Weight loss: with no source of glycogen to use as energy during fasting, the body resorts to burning stored fat, which leads to potential weight loss. Research suggests that exercising during a fasting state decreases body weight, free fat mass, and fat mass

Do You Have to Work Out During Intermittent Fasting?

Exercising is not necessary during intermittent fasting, however, it is beneficial because it can enhance the effects of fasting and weight loss. It might sound excessive to engage in physical activity when you are already limiting your body’s energy intake. Nonetheless, both methods make your body break down stored fat, therefore blending them to boost your fasting results is a clever idea. Use the Fastic app to safely and effectively integrate these two activities. Get exercise and fasting regimen recommendations that adapt to your routine and goals.

Is It Safe to Work Out While Intermittent Fasting?

No question that exercising promotes good health, but is it ok to work out while fasting? The general answer is yes. Working out during fasting is not detrimental to one's health as long as it’s done correctly by following the right precautions and adapting the exercise to a fasting regimen. 

Let's go over the main aspects to be aware of to safely exercise during intermittent fasting. 

Hydration and Electrolyte Balance 

Staying hydrated is essential during fasting. With not as much or any food intake going into our body, drinking more water than usual is recommended. Replenish electrolytes lost during exercise by drinking zero-calorie electrolyte drinks.

Balanced Meal

Eating a balanced meal is imperative to support your body’s health. Restore your body with nutrient-dense foods so it recovers and fuels up for the following fasting hours. 

Integrate the following nutrients into your everyday meals:

  • fiber

  • protein

  • healthy fats

  • vitamins and minerals

  • antioxidants

  • complex carbohydrates

Listen to Your Body

Be aware of your body’s signals. You know your body better than anyone. Be careful not to overdo your workout. If you feel dizzy or lightheaded, stop and take a break. 

How to Workout While Intermittent Fasting?

So, you can work out, but what type of exercise is allowed and how should you go about it? There are a few rules to adhere to for safe and effective exercise while fasting. 

Ease Your Body into It 

Lightly introducing your body to exercise will help it get used to it. Start with simple exercises for short periods and gradually increase the intensity.

Keep Track of Workout Length

Fasting exercise should not be as long as your regular exercise. Workout sessions should be short in time. Start with 10 to 15-minute workouts and progressively extend the duration as your body adapts.

Low to Moderate-intensity Workouts

The type of exercise you do will depend on the type of fasting regimen you are following. If you are doing an intermittent fasting plan with a daytime eating window, then you can opt for moderate-intensity exercises, like:

  • hiking

  • jogging

  • brisk walking

  • dancing

  • circuit training

Conversely, if you are doing alternate-day fasting (over 24 hours without food), then you should aim to exercise on eating days. Nonetheless, if you want to workout on non-eating days, you should do low-intensity exercises, such as:

intermittent fasting and muscle building

Can You Do Muscle-Building While Intermittent Fasting?

During intermittent fasting the body resorts to stored fat for energy. However, if the fat stores are insufficient, the body will proceed to break down muscle protein for energy resulting in muscle loss. So, yes you can do muscle building, nonetheless, to prevent this potential muscle loss, you must follow adequate timing, quality, and quantity of nutrient, calorie, and protein intake. Eating protein after your workout will assist with muscle renewal. The Fastic app helps you monitor your meals to effectively keep track of your daily nutrient intake and support muscle maintenance during muscle building.

Is it OK to Do Weight Lifting While Intermittent Fasting?

Engaging in high-effort exercises like weightlifting while fasting can be acceptable only if you do it during your eating window or have eaten beforehand. Your body requires plenty of energy to endure weightlifting, if you do it in a fasted state you might risk getting hurt or diminish the effectiveness of your workout. So, can you lift weights while intermittent fasting? Yes, but only under safe conditions.

What to Eat When Working Out and Intermittent Fasting?

Eating the right nutrients before and after working out while fasting is also fundamental for optimal performance, adequate recovery, and exercise effectiveness.

Before Exercise 

Opt for digestible foods, such as nuts, fruits, or a small meal of complex carbohydrates for a steady and sustained energy release during exercise.

After Exercise

Prioritize eating protein-rich foods, high-fiber carbs, and healthy fats. Eating protein after a workout aids in muscle repair.

Drinking water and electrolyte-rich beverages before and after a workout is necessary to help prevent dehydration.

When Should You Work Out When Intermittent Fasting?

In general, exercising is best before or after your fast, in other words, during your eating window. Working out during fasting hours is not recommended, this is when the body is the weakest. You can eat before and after your workout to replenish nutrients and recuperate before starting your fasting period again. 

Nonetheless, a study showed that working out in a fasted state leads to the burning of more fat compared to exercising after eating. This means that working out before eating might be more effective for burning fat. 

So, when do you work out when intermittent fasting? The answer depends on your fasting goal. If you want to lose weight, then exercising before eating or in a fasted state is recommended. On the other hand, if you exercise to maintain good physical health or muscle mass, then it is best to exercise during your eating window or after eating. 

Can You Take Pre Workout While Intermittent Fasting?

Yes, you can take pre-workout during your eating hours. Taking it before and after your workout will help you get the most out of your exercise by providing energy and supporting muscle recovery. You can also take pre-workout during fasting hours, however, make sure it is low in calories and sugar to avoid breaking your fast. 

Take the Fastic quiz to find out which fasting regimen best adapts to your preferred exercise regimen. 

Disclaimer: It is advised to speak with a health professional before beginning intermittent fasting or a diet program. There may be side effects for people with certain medical conditions.

With Fastic, millions of people have achieved their desired weight, overcome disease and regained their quality of life.

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