Should You Exercise on an Empty Stomach?

In short, it depends.

As you’d be in a fasted state, as it’s known, it’s often recommended that you work out first thing in the morning before eating breakfast. It’s believed to help with weight loss. But working out after eating may give you more energy and improve your performance.

The fasted state theory is that your body feeds on stored fat and carbohydrates for energy instead of food recently eaten, leading to higher levels of fat loss. Research from 2016 supports this theory, showing that those who didn’t eat before exercising burned more fat and reduced their caloric intake over 24 hours.

However, not all research supports this theory. A 2014 study found no significant differences in body composition changes between groups who ate or fasted before working out. It’s also mentioned that working out on an empty stomach could lead your body to use protein as fuel, leaving your body with less protein, which is needed to build and repair muscles after exercise.

The Advantages

Exercising without prior food intake may prompt the body to use stored fat for energy, particularly as glycogen levels are lower, proving beneficial for those targeting body fat reduction.

Some research suggests that fasting before exercise can enhance insulin sensitivity, a crucial factor in managing blood sugar levels.

It’s also worth noting that fasted workouts may stimulate the release of growth hormones, playing a pivotal role in muscle growth and fat metabolism.

The Disadvantages

Low to moderate-intensity cardiovascular exercises like walking or jogging may be more manageable on an empty stomach, whereas high-intensity cardio or lengthy activities might benefit from pre-exercise nutrition.

For strength training, especially involving heavy lifting, a small meal or snack with carbohydrates and protein about 1-2 hours before the workout can offer energy and support muscle recovery.

Exercising without eating any food beforehand may lead to lower energy levels, making it challenging to perform at your best, especially during intense or prolonged workouts.

Some individuals may experience discomfort, dizziness, or light-headedness when working out without eating, particularly if the workout is intense.

Pros and Cons of Exercise

Everyone’s Different

Some people feel better and perform well with a small meal or snack before exercising, while others prefer an empty stomach.

For people with certain health conditions, such as diabetes, they may need to be mindful of blood sugar levels and may benefit from eating before exercise.

Morning workouts may be more challenging for some people to do on an empty stomach if they haven’t eaten since the previous night. There’s no one-size-fits-all answer.

It depends on your personal goals, the type of exercise you’re doing, and how your body responds. Experiment with different approaches, pay attention to your energy levels and consider consulting with a fitness or nutrition professional to determine the best strategy for your individual needs.

So, which one is it?

While working out on an empty stomach might have some benefits, it’s not without risks and may not be the best approach for everyone.

Always consult with a healthcare professional or a fitness expert before making significant changes to your diet or exercise routine.