For something that should be simple, exercise doesn’t always feel that way. One must choose the best exercise to burn fat. There is the difficult question of whether exercise or diet is the key to weight loss. And now a new question arises: does fasting training lead to faster weight loss?
Bodybuilders swear by it, while some people religiously enjoy their pre-workout protein shake. So what about it? If you want to lose weight, do you have to give up eating and go to the gym on an empty stomach? Unfortunately, like a lot of fitness advice, this question falls into the gray area of ”it depends.” Let’s go.
Why exercise on an empty stomach?
The theory behind working out on an empty stomach is that when you do a cardio session before breakfast, your body burns fat faster. This is because glycogen, a type of carbohydrate that our body stores, is “depleted” overnight. When you wake up and start working out in the morning, because your body is low on carbohydrates, the idea is that it will then turn to fat for energy.
Things get more complicated because if your body is totally devoid of glycogen (you ate dinner early, rested all night, and maybe slept an hour or two longer), the body may not burn fat and turn directly to muscle reserves, which will reduce definition of the body.
5 benefits of exercising on an empty stomach
So what are the benefits, according to science, of skipping breakfast before working out?
1. Burn fat faster
A small study followed 12 active men who ran on a treadmill either after breakfast or while still fasting from the night before. Men who didn’t break their fast, that is, didn’t eat breakfast, burned up to 20% more body fat during the same workouts. What is particularly interesting is that the men who skipped breakfast did not overeat afterwards and did not try to “catch up” on the missed calories early in the morning. Getting ahead of your workout before breakfast can therefore help you lose more fat without causing you to consume extra calories later.
2. Improve your performance
Exercising when carbohydrates are low, such as on an empty stomach, has been shown to improve performance during “normal” exercise. The idea behind it is that training in a low glycogen state helps your body become more efficient at burning fat, so when carbohydrate levels are high, the body is ready and raring to go.
3. Time-restricted eating can help you lose weight
Fasted training is linked to the idea of time-limited eating. On this diet, you can eat as much as you want of whatever you want. The only caveat is that you eat strictly between certain hours, with a 12-16 hour period where you don’t eat anything. The idea is that when our bodies know when to eat, our hormones respond by burning fat and encouraging weight loss during the hours without food. Scheduling exercise during fasting hours can encourage the body to burn even more fat, especially if you exercise first thing in the morning.
4. You can improve your body’s response to insulin
When we eat, our body releases insulin to absorb all the nutrients from the food we eat. But when we eat too many carbohydrates and sugar, our body becomes resistant to insulin – it can’t do its job as well. All that insulin builds up and can cause a wide range of chronic diseases such as diabetes. However, one of the many health benefits of fasting is to reduce this insulin sensitivity. Without constant food, insulin is not formed as often, so our body does not become immune to this hormone.
5. You would like to train more. Let’s be honest: we’re all very busy
By exercising in the morning before you stop to make breakfast, grab a cup of coffee, or anything else that might derail you in the morning, you can burn calories without being distracted. If you have to leave the house at 8 in the morning, it’s much easier to get to the gym before you eat than to eat breakfast, wait to digest it, and then work out.
When it is not a good idea to train without food on board
But working out on an empty stomach might not be the best idea for everyone. For every study that claims fat burning is easier when you exercise before you eat, another study claims the opposite. A study from the International Journal of Sport Nutrition and Exercise Metabolism found that a pre-workout snack or light meal actually helps burn body fat better.
A study published in the Journal of the International Society of Sports Nutrition found no difference in weight loss between women who took a meal replacement before exercising and those who exercised directly without eating.
Another problem is that without fuel in your stomach, you may not work as hard as you could. A pre-workout snack made with a mix of carbohydrates, proteins and healthy fats can give you the energy you need to push yourself. This extra energy can be what you need to perform high-intensity interval training sessions like Crossfit, which help you burn more calories in less time. These are intense training sessions where you will have to give the maximum of your energy.
And if you’re training for endurance sports like cross-country running or triathlons, you can train short distances on an empty stomach, but you’ll definitely need to eat before longer workouts. Depending on the distance you cover, you may even need to refuel during the workout.
Finally, if you’re someone who needs to know mentally that you’re not going to burn out mid-run because you’ve eaten, today is not a good day to exercise on an empty stomach. The same applies to people with diabetes or hypoglycemia. Eating a small snack will keep you safe during your workout.
We would like to say definitively that training on an empty stomach gives better results. But since so many variables come into play: your fitness level, the type of training you do, and how you train best, it’s impossible.
The key is that you stay hydrated before, during and after your workout. Drinking enough water helps maintain energy levels. Since thirst is also mistaken for hunger, drinking enough water can also prevent you from gaining weight. Perhaps more important than whether you eat before a workout is what you eat after. A mix of protein and healthy carbohydrates helps your muscles recover. The ideal is to eat eggs with vegetables within 45 minutes after exercise while the blood is circulating well.
Finally, whether you exercise on an empty stomach or not, congratulations on taking control of your health. Keep training!