Intermittent Fasting And Running To Lose Weight

Intermittent Fasting And Running In Morning

Intermittent fasting and running can be a powerful way to lose weight. It is important to know how to do it correctly so that you don’t undo all your hard work by eating too much or not moving enough. In this post, iFitZone team will talk about intermittent fasting and running, what they are, their benefits, doing it in the morning, and how they work together for weight loss success, even if you run a half marathon and more! 

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    What is intermittent fasting?

    Intermittent fasting is an eating strategy that promotes eating less and burning more fat at certain times each day. There are three major forms of intermittent fasting, with the 5:2 technique, the 16/8 method, and the eat-stop-eat method each having their own advantages.

    For those two days each week when the runner limits their caloric intake to 500 – 600 calories, they are able to eat a normal diet the other five days. In the 16/8 technique, dieters skip breakfast, consume just 800 calories per day for 16 hours, and then fast for another 16 hours. This kind of fasting, in which the dieter does not eat for 24 hours, is referred to as the Eat-Stop-Eat technique.

    What are the main health benefits of intermittent fasting?

    Many health advantages are associated with intermittent fasting, including weight reduction, better endurance, higher insulin sensitivity, greater muscle, and more. Intermittent fasting offers a substantial advantage to cellular repair. As hormone balance and toxin removal are better maintained by the body, this makes it easier for cellular harm to occur.

    The authors hypothesize that increased levels of IF will lead to decreased insulin levels, increased growth hormone levels, and the appearance of norepinephrine. The breakdown of body fat into energy is supported by all of these components.

    What do studies say about the health benefits of intermittent fasting?

    Intermittent fasting helps in your metabolism functioning better, leading to more fat reduction and better insulin sensitivity. According to an article in the International Journal of Obesity, obese men saw significant weight reduction when intermittently fasting.

    A study in the Annual Review of Nutrition revealed that both a reduced night-time eating schedule and a longer night-time fast may promote improved gut health. Our gut bacteria also exhibit daily rhythms of activity, just as we do. This study found that a cyclic intermittent fasting regimen revives microbial health and returns intestinal health to an upright position. Mealtimes and eating earlier in the day may aid in improved metabolism. It may be a successful weight reduction strategy when used in combination with balanced dietary habits.

    Intermittent fasting and running

    Several research findings suggest that intermittent fasting may have health advantages for runners. Intermittent fasting may increase VO2max, assist reduce body mass, and body fat.

    According to research conducted on male runners, those who do running workouts in a fasting condition have improved fat-burning capacities which is beneficial for long-distance running because of the restricted capacity of the athlete’s glycogen reserves.

    Preliminary research conducted in the Journal of Applied Physiology discovered that individuals (men) who often exercised in a fasting condition over the course of six weeks exhibited greater gains in endurance than those who worked out first thing in the morning after eating. Research shows that intermittent fasting may help with post-workout recovery by helping to reduce inflammation and increase nutrition absorption.

    Are there any dangers of intermittent fasting for runners?

    If you, as a runner, are planning on practicing intermittent fasting, you should perform their runs as lightly as possible. It will be bad for both your health and training if they don’t. You may be particularly tired or dizzy if you schedule a strenuous exercise or run while you’re in, or just after you’ve begun your fasting period.

    When stored glucose is exhausted during the normal intermittent fasting phase, the body will need more energy for exercise, therefore it will want the extra glucose it stores, according to Coxall. According to him, endurance athletes run the danger of doing so as a result of being unable to summon enough energy. Based on the findings of a 2020 study in the Journal of Sports Medicine, which found that fasting may lead to diminished performance, distance runners should avoid high-intensity exercise while they are fasting.

    The body is in a constant state of having to produce more cortisol, but it requires the proper sex hormones to make it. Cortisol, the stress hormone, is produced in the body in response to stress. Your cortisol levels are now extremely high, stimulating fat accumulation rather than muscle, so you’re gaining more weight as you attempt to shed it.

    Should you do intermittent fasting as a runner?

    Researchers observed 23 male runners and had them participate in an eight-week trial that focused on the athletes’ normal dietary intake or on a 16:8 eating regimen, which implies that the athletes ate all of their meals in an eight-hour window each day. There was also time set out for sleep over the remaining 16 hours.

    Before and after the two-month period, all participants completed an activity test and supplied blood samples. In order to learn more about their running economy, maximum oxygen absorption, and glucose, insulin, and triglyceride concentrations, researchers performed the following tests:

    Fasting was shown to reduce body mass, but the researchers found no other factors to have been affected. Fasting had no effect on the overall running performance, however, calorie restriction was shown to result in less body mass loss.

    How should runners perform intermittent fasting?

    • Exercise at a modest intensity

    Runners performing an intermittent fast should run at a speed that allows them to maintain an RPE of 2-3 out of 10, or a heart rate of about 70-75% of their maximum rate of sustainable oxygen consumption. Fasted state, they will be using stored glycogen rather than fat, which will be exhausted. Consequently, you run the danger of crashing into the wall. Starving the body from energy and output while you’re at high levels doesn’t help anybody.

    • Reduce the duration

    Runs in a fasting condition should not go more than 1.5 to 2 hours when you start out. After you get more used to longer runs in a fasted condition, you may feel more comfortable pushing the limits. You should eat a 3:1 ratio of protein and carbohydrates as soon as you notice any fatigue or dizziness (within 30 minutes).

    • Move at the optimum moment

    Intermittent or alternate-day fast-running runners should target the times or days when they fuel up. To follow a schedule of running when they are at their most active, they should only eat between 11 a.m. to 7 p.m. 

    Intermittent fasting and running in the morning

    It is critical for runners to refuel correctly in the morning in order to maintain intensity so that muscle atrophy doesn’t occur. Studies show that eating a high protein diet while sometimes fasting helps runners feel fuller and have more energy.

    Long-distance running while fasting

    The findings show that exercising in a fasted state (without food) improves glycogen storage and fat utilization, but training that includes several runs lasting more than 60 minutes in the fasting state has a negative impact on performance.

    Running your long runs on reduced glycogen reserves is said to put your body in a position where it must tap into fat stores to meet energy demands. As a result, your body will use fat as a fuel more efficiently. Actually, the issue we must answer is, does this theory describe reality?

    Fasted cyclists who did training in the morning increased muscular glycogen reserves by 50% compared to those who had breakfast before doing exercise. Intermittent fasting (IF) has been shown to enhance glycogen stores and endurance performance in previous research.


    Intermittent fasting is a popular trend for weight loss. This article discussed the pros and cons of intermittent fasting as well as how runners can perform this technique to maintain their performance while losing weight. If you are interested in learning more about running, fitness, or health topics follow our blog page! We’ll provide helpful articles like these on a regular basis that will help you reach your goals.

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