What to Know About Intermittent Fasting and Working Out

What to Know About Intermittent Fasting and Working Out

by Evelyn Valdez

Intermittent fasting has been a popular eating approach for active people for a while now – and there’s a good reason behind it! Depending on your personal fitness goals, you could reap many benefits from having a scheduled eating pattern and a workout routine properly planned around it.

If you’re not familiar yet, intermittent fasting is a time-approached eating method that focuses on when you eat instead of what you eat. It doesn’t tell you which foods you need to include in your diet, just the feeding and fasting windows depending on your lifestyle and what works best for you!

This method is commonly used to reduce the calories consumed during the day, but the benefits extend beyond that as it is a great tool for those who are looking to reach their muscle-building and weight-loss goals. We’ll show you all the benefits of intermittent fasting, how to incorporate it into your routine, and the safest way to train while fasting, so keep reading!

Intermittent fasting and exercising

Being able to decide what to eat isn’t the best thing about intermittent fasting. This eating approach is known for having many benefits, both inside and outside of the gym:

  • Improves weight loss and fat burning
  • Promotes lean muscle growth
  • Can reduce insulin resistance
  • Helps induce cellular repair processes
  • Can reduce inflammation in the body

But before you dive head-first into intermittent fasting, we’ll show you a breakdown of what to do and what to expect whether you’re fasting to lose weight or to build muscle so you can maximize fasted workout benefits.

Fasting for weight loss

Since intermittent fasting is primarily a method to eat fewer calories in a day, you might have guessed that it works wonders for those on a weight loss journey. Not only because you’re consuming fewer calories, but also because of how your body uses energy during exercise.

Here’s how to fast if your main goal is weight loss:

  • Train near the end of your fasting window
  • Your body needs energy to move, which usually comes from carbs turned into glycogen in your body. If you don’t feed your body carbs before a workout, your body will look for another source of energy, at that source will be your fat storage!

    Simply put, exercise on an empty stomach leads to more body fat burned during exercise. Make sure you do it near the end of your fasting window, or at the very beginning of the feeding window before any meal so you can properly replenish your body with carbs and protein post-workout to recover.

  • Avoid overeating during your feeding windows
  • The whole idea behind working out during your fasting windows is to maximize fat burning, but this won’t work if you’re overeating whenever you can.

    If your goal is weight loss, you need to make sure you’re actually reducing the calories that you eat. You might have less time to eat during the day, but the only way to keep a calorie deficit is to watch how much you eat and the quality of your foods during your feeding window.

    Fasting for strength training

    Now, if your goal is to build more muscle, intermittent fasting can be tricky, but there are ways around it! 

    As you now know, fasting leads to weight loss and fewer calories eaten, which can also cause significant muscle loss. This, of course, isn’t ideal if you’re looking to build a strong physique. To avoid this, here are the two main things to keep in mind if you’re fasting while strength training:

    • Train during your feeding window after your first meal

    Since you’re not focusing on weight loss, you don’t need to make your body tap into your fat storage. Instead, make sure to eat properly before your workout, preferably with enough time to also eat after.

    This way, your body will be able to perform properly during your workout and then effectively repair muscle damage and build new muscle tissue on top for bigger and stronger muscles.

  • Keep your carb and protein intake higher
  • To avoid losing muscle mass during long fasting periods, you need to make sure you’re eating enough calories through high-quality carbs and protein during your feeding window to make up for the calories that you’re not eating during the fasting window to support the muscle-building process.

    Which fasting method is best for you?

    There are several intermittent fasting methods that you can try, but ultimately choosing which one to follow will depend on a few factors, such as if you’ve fasted before, your daily schedule, your personal health needs, and of course your fitness goals. These are the most popular methods for active people:

    • 16/8 method. It involves fasting for 16 hours with a feeding window of 8 hours, such as eating from 12-8 p.m. and then fasting the rest of the time.
    • Circadian rhythm method. This method follows your internal body clock, and it involves eating during daylight hours when your metabolism is most active and fasting at night.
    • 5:2 method. This one involves having a regular eating schedule 5 days a week, and then choosing 2 days (not back to back) to limit your calorie intake to just 500.

    Whether your goal is building muscle or losing weight, the 16/8 method is widely regarded as the best one to begin with. Not only because it’s easier to get used to, but also because you get to decide your feeding hours, making it more flexible than other methods.

    Tips for working out safely while fasting

    If you’ve made up your mind about trying intermittent fasting as an active person, make sure to approach it safely so you can reap all the benefits without burning yourself out in the process. Here are a few tips to keep in mind:

    Stay properly hydrated

    Fasting doesn’t mean that nothing will reach your stomach during that time – just solid foods! Drinking water and other beverages such as tea and coffee are perfectly fine, and in fact, it’s encouraged.

    Staying hydrated is key to healthy fasting. Water also comes from food, and if you’re reducing your feeding times then you need to compensate with enough water to help your body get through each day and each workout effectively.

    Work your way up to it

    Remember what we said about starting with the 16/8 method? Well, even that method can be tough to break into if you’re not used to fasting, so make sure you start slowly at first.

    You can switch the hours to 12/12, with equal fasting and feeding times, and slowly change it an hour at a time. For example, 13 hours of fasting and 11 of feeding, then 14 hours of fasting and 10 of feeding until you get to the 16/8 ideal ratio.

    Pay close attention to your meals

    We’ve said it before and we’ll say it again: high-quality foods are the key to an effective intermittent fasting approach – and any fitness approach for that matter!

    Your meals should be packed with complex carbs, lean proteins, and healthy fats that can support a fasting lifestyle without letting your body crash from a lack of nutrients. And remember to prioritize carbs and protein if you’re on a muscle-building journey.

    Only do heavy lifting after a meal

    Not only heavy lifting but also other forms of high-intensity activities such as HIIT training and CrossFit require high amounts of energy, so it’s best to have some carbs in your system beforehand.

    Make sure you eat properly before you try any of these activities so that you can keep a good performance throughout your workout!

    Listen to your body

    Beware of the side effects if you’re intermittent fasting. These could range from simple hunger to headaches and dizziness since you’re not used to fasting at first, which is why we recommend starting slow.

    If these negative effects persist, consider changing your fasting method or stopping it completely. Your health comes first, so make sure you always listen to what your body is saying!

    The best method is the one that works for you

    Intermittent fasting might not be for everyone, so be careful when trying it out! Switch methods if the one you chose isn’t working for you, or try a completely different eating approach that actually supports your goals without draining you in the process. The ultimate goal is to have a healthy fitness journey, so good luck!

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    1 comment

    • Do not eat any solid food after 6 in the evening and that is the best intermittent fasting anyone could do. We can drastically lose weight and feel light, this change could be seen right from the Day1!! It is truly magical!!!

      Swarnna Mangalampalli -

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