16:8 intermittent fasting and morning workouts [Get the benefits] 

Written by Aly Owen

Medically reviewed by Louise Bula, RD

Published on March 1, 2024 | Updated on March 28, 2024

Looking to lose weight, burn fat, or boost your metabolism? A 16:8 intermittent fasting morning workout may be the one-two punch that helps you knock out your goals. 

But how do you mix fasting and working out in the morning safely and effectively? 

Here’s what our experts say about intermittent fasting and morning workouts. 

Is 16:8 intermittent fasting and working out in the morning safe? 

From sunrise cardio to fasted lifting in the morning, exercise and intermittent fasting can work well together.

The key to a safe fasted workout in the morning is figuring out how to exercise while fasting in a way that supports both your physical and psychological needs. That means finding a plan that is sustainable, prioritizes your well-being, and fits your goals. 

Just like fasting in general, though, combining a morning workout and intermittent fasting may not be safe or right for everyone, and generalized advice around exercise or intermittent fasting by body type may not apply to you. That’s why you should always talk to your doctor before making any changes to your eating or lifestyle habits. 

We can also help you find a SIMPLE plan that connects your goals, needs, and preferences. Take our SIMPLE quiz to tell us about you and what you want to achieve, and we’ll help you get started, stay on track, and hit your targets. 

Is it effective? 

So, working out fasted in the morning may be safe, but is it effective? 

Although some studies show no difference in body composition between working out “fed” versus working out fasted,[1] a fasted morning workout can effectively supplement common fasting goals, including fat loss, and support overall health (more on the benefits in the next section!).[2]

However, how you define “effective” comes down to your goals. For example, if you’re looking to bulk, lifting weights fasted in the morning may not be the most effective choice, as your body could end up burning muscle to use as replacement fuel.  

Benefits and drawbacks of combining 16:8 intermittent fasting with a morning workout

Whether your intermittent fasting morning workout schedule involves cardio or fasted weight lifting, working out on an empty stomach may: 

• improve fat burning [3]
• benefit weight loss and management [4]

Psychologically, intermittent fasting and early morning workouts may also be an easier routine to stick to since exercising first means fewer potential interruptions or excuses can get in the way. Good morning, sense of accomplishment!

On the flip side, if your morning is already jam-packed with Important Things to Do, an intermittent fasting 5 AM workout may be tough to stomach. Literally, too — fasted workouts may increase hunger if you don’t eat shortly after,[5] and you may be more prone to side effects like dizziness and lightheadedness if you’re not properly hydrated. 

Over time, if you don’t get enough fuel to recover, you may also experience exhaustion, injury, and illness, and your metabolism may slow down. (As long as you fast well, the answer to “Does intermittent fasting slow metabolism?” is “no”!). As always, remember to consult your healthcare provider before making any significant lifestyle changes, especially if you have any medical conditions or take any medications. 

Tips on practicing 16:8 intermittent fasting and morning workouts 

1. Figure out your workout goals. Before you start combining morning workouts and intermittent fasting, you want to know why you’re working out — what results do you want? This “why” informs the what and the how. It’s also good to consult your healthcare provider, as they can help you optimize your workouts without compromising on your needs. 
2. Ease into it. Even if you’re already used to intermittent fasting, when working out in the morning after an overnight fast, you may find you have less energy or get hungrier faster. Start with shorter, lighter workouts and check in with yourself. “No pain, no gain” is not a good mantra for safety, and we recommend saving high-intensity workouts for eating windows.    
3. Drink A LOT of water. Staying hydrated is super important for any fasting experience, but especially so when you add in some sweat action. Our “what you can drink while fasting” guide has more tips on fasting-safe drinking habits. 
4. Fill up on nutrient-dense foods. Fight off hunger pains and ensure your body has the fuel it needs pre- and post-workout by focusing on health-promoting foods during your eating windows. Use our guide on what to eat during fasting for ideas!
5. Experiment with different timings, activities, and approaches. There’s no one-size-fits-all guidebook for how to intermittent fast and work out in the morning. It’s all about finding what intermittent fasting schedule and morning workout combo works best and is most enjoyable for you — if any! Our intermittent fasting and working out guide can help, too.  

Written by Aly Owen

Medically reviewed by Louise Bula, RD

Published on | Updated on March 28, 2024