Should I Exercise On Days Where I Do Intermittent Fasting

Intermittent fasting goes well for many people to help get control of their diet and some health concerns. It makes many people feel good.

But, it can be a confusing time. Some people feel fabulous on the days they fast, while others may feel a little tired and sluggish.

Maybe you've tried exercising while doing your fast and just don't find it… right.

That's okay, many people feel the same way. Exercising during intermittent fasting can be a little odd because you're changing the way your body behaves. Let's look at the ways exercise works.

Why Does My Body Feel So Odd When I Fast?

intermittent fastingWhen you do a fast, you stop your regular intake of food.  This causes a lot of changes in your body. Sometimes, these changes can make you a little tired and lethargic, especially if you're used to eating more carbohydrates.

For normal, healthy people, skipping a few meals doesn't produce many changes in your body. Younger people and healthy people can do intermittent fasting and not feel any changes in their bodies. They're the type of people who can do a regular cardio exercise during the fast and be perfectly fine.

But, most people who do intermittent fasting are doing it for health reasons. They're trying to control their sugars, lose weight, or do something to bring them into a healthy state.

For these people, intermittent fasting can hit hard. You may feel when you are exercising you don't have any energy or it takes a long time to recover.

That's normal.

If you're doing intermittent fasting to control your blood sugars, you may find your energy crashes in the evening of the fast. You get very tired. It's tough if you're used to exercising in the evenings. That's because your body lacks its usual energy source: the sugars.

You might start feeling tired and shaky if you try to do strenuous exercises when you're fasting and your sugars get low.

The second aspect of intermittent fasting is it lets your digestive system calm down and almost go to sleep for the day as you're not eating. While it's normal to have your digestive system go to sleepit can affect your energy levels, sending signals to your body that you need to conserve your energy. That can make any kind of exercise hard.

The Big Question: Should You Exercise While You Fast?

intermittent fastingThe answer is yes, you should be exercising while you do intermittent fasting IF you usually exercise on that day.

But, we do recommend a lower-intensity exercise. If you're used to doing cardio or strength training, we suggest doing something softer, such as Pilates or yoga. Step down your routine, so your heart rate does not go as high, and you're not expending so much energy.

It's not that your body doesn't have the energy, it's that you're burning energy without a fast, easy replacement. That makes you tired. The whole point of intermittent fasting is to feel good.

Top Three Types of Exercise To Do During Your Fast

Let's take a look at three types of exercises that are perfect for when you're intermittent fasting.


This type of exercise focuses on small, repetitive movement and the body's resistance to create muscle tone. Generally, Pilates is not an aerobic exercise, but it is muscle intensive. If you're used to doing cardio or strength training, this is a perfect step down during your fast.


Yoga is slower and more dependent on muscle strength than on cardio activities or fast movement. Be sure to check with the class to understand what type of yoga is being offered. Some moves much faster than an exercise routine, and some even incorporate higher room temperatures to encourage sweating. You want the slower and more relaxing yoga if you're not used to a faster pace or higher temperatures.

Gentle Stretching

stretchingIf you're not used to exercising heavily or much at all, just stick to gentle stretching during the day. Take 20 minutes to a half-hour to slowly go through all your muscles and hold each position for 20 to 30 seconds. The stretching will help increase your blood flow and heart rate, but not enough to truly fatigue you.

We hope you enjoy doing intermittent fasting and get all the benefits. Take care while you're exercising, but you don't need to skip exercise day just because you're fasting.