How to Time Workouts with Intermittent Fasting

There are many reasons why celebrities, influencers, dietitians, and doctors are so keen on intermittent fasting. Not only has it been a proven method for weight loss, but it also has the power to help clear mental obstacles and restore energy.

But, if you’re trying to work out while fasting, you could find yourself in a bad situation very quickly. Because fasting means cutting out certain foods, or all foods all together, your body might be experiencing a change in energy levels.

The key to fasting and workouts is to make sure that you’re doing a limited number of energy-sucking workouts. Dr. Gabrielle Fundaro, an exercise scientist and sports nutritionist, believes that cardio can be a particularly draining exercise that should be limited while you’re fasting.

“If you’re doing 30 minutes of cardio, that’s fine to do fasted,” said Fundaro. “But, if you’re doing cardio for much longer than that, your body is going to rely on stored glycogen – sugar used for energy for intense activities – to fuel your workout and your performance may not be as good.”

Not only can your performance suffer, but your body can, too. If you push yourself too hard during a workout and fasting period, you may pass out or cause unneeded damage to your organs.

Bottom line, don’t compete in any competitions if you’re fasting. According to Fundaro, workouts that are fueled with good, nutritious food will always leave an athlete feeling better. However, if your trying to limit the food you’re eating, Fundaro suggests having a small snack or small meal three and a half hours prior to your workout.

This gives the body time to process the sugars in the snack or meal. They will be ready to use as energy when you start your workout. Some great snack options include peanut butter on toast, yogurt, and apples or some other fruit.

All of these tips from Dr. Fundaro are monumentally important if you’re doing weight training rather than cardio training. Scheduling your workouts around your fasting periods is very important if you want to see results. When your body lacks fuel, it can sometimes start breaking down muscle proteins to help fuel workouts. Additionally, you may increase your likelihood of damaging and tearing your muscles when your body doesn’t have the energy it needs to fuel your workouts.


At the end of the day, Dr. Fundaro says that the ultimate key to intermittent fasting and scheduling your workouts is simply listening to your body. If your body feels hungry or lacks energy, you should have something to eat.

If you avoid what your body is telling you and, instead, chase after the prospects of losing weight or gaining muscle, you may end up injuring yourself or causing small injuries that could become a bigger deal down the line.

Properly schedule your fasting so that you’re having at least a small meal a few hours before hitting the gym for a cardio or weight training session!