Exercise on an empty stomach, also referred to as a “fasted” state, is called “fasted cardio”. This is typically performed in the morning before your first meal. There is a hypothesis that suggests exercising when fasting for a longer period or on an empty stomach to maximize fat loss. Although some fitness experts support this hypothesis, it is still widely contested in the fitness community and has no supporting scientific data.
Whether or not to work out on an empty stomach is essentially a personal choice, as the effectiveness of the fasted cardio idea is still debatable. Should you want to adopt the fasting cardio approach, there are some disadvantages to consider.
Here’s a look at some of the research that has been conducted to put the fasted cardio concept to the test!
How to Perform Fasted Cardio
When it comes to fasted cardio, most people work out first thing in the morning, before consuming breakfast. If you can tolerate it, a moderate-intensity workout lasting 30 to 45 minutes is advised. Less time spent working out also helps one reach the weekly recommended number of 150โ300 minutes of moderate-intensity exercise (1).
A bodybuilder and author, Bill Phillips is recognized for having popularized the fasted cardio idea in 1999. According to Phillips, exercising while fasting optimizes fat burning in the human body. His idea of fasted cardio has been popular ever since the book’s success.
Phillips claims that an overnight fast lowers insulin levels, glycogen storage, and blood sugar. Our bodies normally get their energy from these glycogen stores, which are derived from the carbs in our food. But if you work out while fasting (that is, with less glycogen in your body), the idea is that your body will then use body fat as fuel to power your workout.
Do Fasting Exercises Work?
Although there are fitness industry pros that use the fasting cardio method and report some fat-burning benefits, the effectiveness of this hypothesis has not been fully confirmed by scientific studies.
Researchers examined five different studies with 96 people in total to assess the efficacy of exercise following an overnight fast in a study (2). The review authors’ investigation revealed that exercising after a fast had very little, if any, impact on body mass.
Eating could assist you finish your exercise regimen, while fasting might make it more difficult to finish a workout. According to an assessment, which examined 46 previously published studies, study participants were able to exercise for longer durations of time if they ate before a cardio session (3). Exercise after eating resulted in longer aerobic sessions, indicating that although fasted cardio has potential advantages, longer workouts are not always the outcome.
Related Post: Balancing Act: How to Reap the Benefits of Aerobic vs. Anaerobic Workouts
It’s critical to keep in mind that exercise has advantages regardless of whether it is performed after eating or while fasting. According to the fasted cardio idea, you may be able to maximize the impact of your workout on burning fat if you can do it without eating. Whether or whether exercise is done on an empty stomach, weight loss and a reduction in body mass are probably the outcome of an overall calorie deficit.
Advantages of Fasted Cardio
While the hypothesis behind fasted cardio has received little scientific backing, other studies have indicated that athletes who fast have lost meaningful amounts of body fat.
One study examined how fasting affected resistance training (4). Twelve female athletes were included in the study; each participated in two exercises. One resistance training session followed a 10-hour fast, whereas the other after a meal high in fat and carbohydrates. After the two workouts, the researchers discovered that the body was able to use more fat than carbs for energy during the fasted session.
This study offers more insight into the impact of fasting on exercise and body composition, albeit focusing on weight training rather than cardio.
Fasting the night before and fasting before a morning workout can also help athletes who don’t wake up early save time. It’s not necessary to get up early to make time for eating before a workout when you follow a no-meal, pre-exercise regimen. Rather, savor the few more minutes of sleep.
Within an hour or so of finishing your workout, you should consume a balanced meal of carbohydrates and protein. Among the choices are:
The Risks of Fasted Cardio
Even though fasted cardio may help reduce body fat, there are a few possible disadvantages to this diet and exercise strategy that should be considered.
You can make up for it by eating extra at other times if you know you’ll be working out while fasting. According to one study, people who knew they would exercise without eating in the morning ate more calories the night before (5).
Further studies have found that fasting can cause protein loss and, eventually, muscle atrophy. These data suggest that if you want to gain muscle mass, fasted cardio may not be the best option (6).
Similarly, fasting cardio may not result in longer sessions. If you want to do endurance activities, such as marathon training, fasted cardio may not be the greatest option. A study found that eating before a workout can naturally result in a longer endurance aerobic session. Working out while fasted, on the other hand, may result in a shorter workout time.
Before beginning any new exercise program or if you have any medical issues that could cause you to feel lightheaded or dizzy while fasting, consult a healthcare professional. After working out while fasting, if you feel ill, stop, and have a well-balanced meal. If necessary, follow up with a medical professional.
To Wrap Things Up
It is up to each individual whether to engage in fasting cardio. Whether you eat before or not, regular exercise has definite health advantages, including the potential for long-term, healthy weight loss. It is advised to start slowly if you have never worked out before eating breakfast. Find forms of exercise that suit your lifestyle and give your body time to adjust to any changes in diet and exercise regimen.
Don’t have time for the full article? Read this!
The article explores the controversial concept of fasted cardio, exercising on an empty stomach for potential fat loss. It discusses the origins, mechanisms, and scientific support for the idea. The advantages, risks, and potential drawbacks are outlined, emphasizing the importance of an overall calorie deficit for weight loss. Personal preferences and consultation with a healthcare professional are recommended before adopting fasted cardio.
Sources |
- Top 10 Things to Know About the Second Edition of the Physical Activity Guidelines for Americans | health.gov
- JFMK | Free Full-Text | Effect of Overnight Fasted Exercise on Weight Loss and Body Composition: A Systematic Review and Meta-Analysis (mdpi.com)
- Effects of fasted vs fedโstate exercise on performance and postโexercise metabolism: A systematic review and metaโanalysis – Aird – 2018 – Scandinavian Journal of Medicine & Science in Sports – Wiley Online Library
- Effects of Prior Fasting on Fat Oxidation during Resistance Exercise – PMC (nih.gov)
- Planned morning aerobic exercise in a fasted state increases energy intake in the preceding 24 h | European Journal of Nutrition (springer.com)
- Is muscle and protein loss relevant in longโterm fasting in healthy men? A prospective trial on physiological adaptations – Laurens – 2021 – Journal of Cachexia, Sarcopenia and Muscle – Wiley Online Library
wealthjourneycompass says
Great info.
Jasmine Feliciano says
Thank you kindly!