Check any social media platform or search online for health and fitness information; you will surely find that someone prefers to train on an empty stomach.
Although it seems that intermittent fasting is hogging too many covers, this lifestyle and diet is not new. There is research that affirms the benefits of training on an empty stomach, but you have to do it in a planned way. Below you will discover what the experts recommend to exercise safely.
Main benefits of training on an empty stomach
Not only do you have to rely on personal experiences, you also need to know what science can show about the benefits of this type of training. It’s known for using fat better, but is it real?
Increase growth hormone
Both fasting and exercise increase human growth hormone. Two days of fasting have been shown to increase this hormone, although its purpose is not actually to build muscle. Growth hormone seeks to use stored fatty acids and glucose as energy and, in extreme cases, eliminate amino acids from the muscles and redistribute them to the organs that are necessary for life, such as the heart, lungs, kidneys, liver, etc.
If you train on an empty stomach, at most you will tell your body to keep some of the muscle it has, but the hormone alone and in physiological amounts gained helps you gain muscle. In fact, science suggests that growth hormone supplementation does not help adults build muscle. To gain lean muscle mass, you need protein and the boost (strength training).
Ketosis state
When you fast, your blood sugar and insulin levels remain low, keeping you in ketosis. To maximize ketogenic potential and burn fat, focus on low intensity exercise .
This type of exercise can be a useful tool to help type 2 diabetics improve blood sugar levels. But if you’re already on a low-carb or ketogenic diet, you may not need to train on an empty stomach – you’re already getting most of its benefits from the diet.
Burning fat and calories
The main argument in favor of fasting training is that it burns more fat. When we fast, insulin levels drop, allowing body fat to separate (through lipolysis) and oxidize (burn) as free fatty acids. Fasting also depletes glycogen stores, which means less glucose is available for energy during exercise. So fat should replace that glucose for fuel during fasting activity.
In practice it is more complicated than that. Specifically, the amount of fat burned depends on the amount of fasting exercise. For example, performing low intensity aerobic exercise (walking, light jogging, etc.) on an empty stomach appears to improve fat burning. When someone eats carbohydrates before exercising, they reduce fat oxidation, probably due to an increase in the hormone insulin. But moderate or intense cardiovascular exercise is different. During moderate and intense exercise, fat oxidation is approximately the same both in the fed state and in the fasted state.
Are there any downsides?
Studies have argued that intermittent fasting and long-term exercise are not ideal. Some claim that the body depletes itself of calories and energy, which could end up slowing down the metabolism. Here are some other risks that could appear.
Loss of muscle mass when training on an empty stomach
If someone wants to gain muscle, it is not recommended too much fasting. Fasted training, especially cardio, appears to accelerate protein breakdown in muscle tissue. However, eating before cardiovascular exercise can slow the rate of this breakdown by keeping glycogen stores full. But keep in mind that this usually happens only in high-level, performance-focused athletes. An athlete like any of us who is focused on fat loss does not need to go up on carbs.
If you want to gain muscle, you should eat leucine-rich proteins (such as whey) in the hours around strength training. That is, you don’t need carbohydrates to build muscle – whey protein itself can increase insulin, preventing muscle catabolism. Protein and strength training works quite well.
Training on an empty stomach gives less energy
Some types of exercise (HIIT, heavy lifting, etc.) require a great deal of effort to get the maximum benefits. But when you train on an empty stomach, it is impossible to exert yourself 100%. Fasting is simply not suitable for peak performance.
Also, if you force yourself to train on an empty stomach day after day, you may not regain that low energy state and you will start to hate exercise.
Brings too much stress
Fasting is a stressor, as is exercise. These stressors, applied correctly, induce a hormonal response, a beneficial adaptation to stress. When you stress your muscle fibers by doing five sets of heavy squats, they repair, adapt, and get stronger.
But you have to be careful. The body has a limited capacity for stress, and if we exceed that capacity, we can suffer. For beginners, the first thing to do is reduce the training load, especially cardio. Fat loss comes from diet, not training, and training is for building and improving health. Overtraining can increase cortisol, which can make weight loss difficult.
Tips for safe fasting training
To take a step into fasting training, there are a few things that can be done to make your training effective.
Control the hours of fasting
There are three considerations to making your training more effective while fasting: whether you should exercise before, during, or after. A popular method of intermittent fasting is the 16: 8 protocol. This involves consuming all foods within an 8 hour window and then fasting for 16 hours.
Exercising before the window is ideal for someone who performs well during exercise on an empty stomach, while during the window is more suitable for someone who does not like to exercise on an empty stomach and also wants to take advantage of nutrition post workout. For performance and recovery, the best option is to train for those hours.
Choose the type of training according to your macronutrients
It’s important to pay attention to the macronutrients you eat the day before you exercise and when you eat afterward.
For example, strength training generally requires more carbohydrates that day, while cardio or high-intensity interval training (HIIT) can be done on a low-carb day. In case of doubts, it is best to go to a dietician-nutritionist for correct advice.
Eat proper foods after training
The best solution to combining intermittent fasting and exercise is to schedule your workouts during your eating periods so that nutrition levels peak. And if you lift a lot of weight, it is important that your body has protein after training to help with regeneration.
The success of any exercise or weight loss routine depends on how reliable you are to maintain it over time. If the end goal is to decrease body fat and maintain fitness level while maintaining intermittent fasting, it is important to stay in the safe zone.
- Eat a meal close to moderate to high intensity training . In this way, the body has some glycogen stores to take advantage of and fuel the training. For example, if the next day you are going to train cardio or resistance, it is advisable to have a carbohydrate-loaded dinner.
- Stay hydrated . Fasting does not mean eliminating water. In fact, it is recommended to drink more water on an empty stomach.
- Keep your electrolytes high. A good low calorie source of hydration is coconut water. It replenishes electrolytes, is low in calories, and tastes pretty good. Gatorade and sports drinks are high in sugar, so avoid drinking too much.
- Keep the intensity and duration fairly low . If you try too hard and start to feel dizzy or lightheaded, take a break. Listening to your body is important.
- Consider the type of fast . If you are doing a 24-hour intermittent fast, it is recommended to do low intensity workouts such as walking, yoga, or gentle Pilates. But if you’re doing 16: 8 fasts, much of the 16-hour fasting period is at night, sleep, and early in the day, so sticking to a certain type of exercise isn’t that critical.
- Listen to your body . If you start to feel weak or dizzy, you are likely experiencing low blood sugar or are dehydrated. If that’s the case, opt for a carbohydrate drink and then continue with a well-balanced meal. Although exercise and intermittent fasting may work for some people, others may not feel comfortable doing any type of exercise while fasting.
