While the outcomes of intermittent fasting (IF) sound brilliant, many people are worried about the impact this behaviour has on their daily routines. If you’re active or enjoy long runs, you’re probably concerned about IF leaving you drained and tired.

This is certainly something that worried us at Ready Sweat Go. IF is a great way to boost focus and reset your body. However, if it means we can’t run or workout at our best, is it worth it?

This article considers this problem and hopes to help you embrace intermittent fasting while leading an active lifestyle.

Time is a crucial component of IF, and getting your timing correct is essential to have enough energy to workout to a level you’re happy with.

Early Morning Training

Exercising first thing in the morning can work brilliantly if you’re following a common fasting pattern like 16/8 (where you eat between 12pm and 8pm). Your body has had time to digest yesterday’s food, and many people find they have steady energy levels at this time. Plus, it’s often easier to exercise before the day gets busy.

Training Close to Your Eating Window

Some people prefer to exercise just before they break their fast. This can work well if you’re doing an afternoon workout before an early evening meal.
Just be aware that you might feel a bit hungry towards the end of your session—that’s completely normal, but maybe don’t overdo this.

Different Fasting Schedules

If you’re doing alternate-day fasting or a different pattern, try to plan your more challenging workouts for your eating days.
On fasting days, stick to gentler activities like walking or light yoga if you want to move.

Try to match your more intense workouts with when you have the most energy. For example:

• If you eat between 12pm and 8pm, a morning workout might suit you
• If you eat between 6pm and midnight, an evening workout could be better

Planning Your Workouts

We won’t tell you there is a best time to work out, there’s no universal solution that fits everyone. This means you’ll need to figure out the right time for you. Pay attention to:

• When you naturally have the most energy
• Your work and family commitments
• How you feel during different types of exercise
• Your sleep patterns

No matter what type of activity or exercise you enjoy, there are ways to combine it effectively and safely with fasting.

Cardiovascular Activity

Activities like walking, leisurely cycling, or light jogging are brilliant choices when fasting. These are great because:

• Your body can readily use fat for fuel at these lower intensities
• They’re less likely to make you feel dizzy or overly tired
• You can do them for more extended periods without running out of energy

High-Intensity Training (HIIT)

While you can do HIIT while fasting, it needs a bit more care:

• Keep sessions shorter than usual (15-20 minutes is plenty)
• Consider doing HIIT closer to your eating window
• Listen to your body - if it feels too hard, dial it back

Working with Weights

When lifting weights while fasting:

• Focus on maintaining rather than setting new records
• Keep sessions under an hour
• Use slightly lighter weights than usual if you’re feeling less energetic
• Rest a bit longer between sets if needed

As we’ve already discussed in our IF hub, breaking your fast in the right way is vital, but it’s also crucial when you’re exercising. However, as is often the case, you don’t need to complicate matters; a simple approach is best.

Try to eat within your usual post-workout window and have something simple yet nutritious. If you use protein shakes, stick with that.

Other people will find lean protein like fish or chicken to be the best option. Add in some complex carbs like a sweet potato and then some vegetables, and your body will thank you.

As we’ve already said, it’s all about how you respond and react, so try different approaches. When you find something that works (and you like it, it’s best to have a routine you can stick with), keep doing it.

This also goes for your personal goals, with a weight-loss diet being different from a muscle-gain diet.

Don’t Lose Sleep Over Balancing Fasting and Working Out

The timing of fasting, not to mention the quality of breaking your fast, is important when working out. However, it’s not important to fret and fuss over it or let it put you off. Take a sensible approach, try to eat and do the things you would typically do, and be mindful of how you feel.

As with everything, it’ll probably help you plan ahead, and you should stay hydrated. Before you know it, you’ll be exercising around a fast without a second thought. If you balance exercise with fasting, and you have some tips, let us know and we’ll be happy to share them with others.

Resources:

Healthline - How to Exercise Safely During Intermittent Fasting - https://www.healthline.com/health/how-to-exercise-safely-intermittent-fasting

Science Focus - Intermittent fasting and correctly timed workouts key to fat loss, says study - https://www.sciencefocus.com/news/time-restricted-eating-high-intensity-exercise

Chatswood Medical Centre – 16/8 Intermittent Fasting Morning Routine - https://www.shchatswoodmedicalcentre.com.au/16-8-intermittent-fasting-morning-workout/

Medical News Today - Can you workout while doing an intermittent fast? - https://www.medicalnewstoday.com/articles/intermittent-fasting-and-working-out