Is it best to eat before or after a workout? This is probably a question you've pondered, especially while on a weight loss journey. And, it seems obvious that engaging in cardio on an empty stomach is surely the best option for fat loss.
Let's dive in and see if that's the case. Here's what you need to know about fasted cardio.
What is fasted cardio?
In many ways, fasted cardio is exactly what it sounds like. It refers to fasting, or abstaining from all food and drink that isn't water, before performing cardio exercise on your empty stomach.
Exercising after waking up is recommended as you've already been 'fasting' overnight while sleeping. This overnight fast usually lasts between 8 to 12 hours, making it a good time for a fasted cardio workout [1].
This means completing your morning workout after you get up but before you eat breakfast or have a cup of coffee — this is truly fasted cardio. Fasted cardio has potential benefits and risks like all types of exercises.
But, what is the actual point of fasted cardio? And how does it encourage weight loss?
Does fasted cardio burn fat?
The main idea behind fasted cardio is the ability for fat burning to occur, given you haven't eaten recently.
Early studies have found that fasted cardio burn can induce higher body fat oxidation. Fat oxidation refers to the various processes that cause your body to generate energy for bodily functions such as muscle contraction and the repair of body tissue — 2 functions crucial to the building of muscle mass.
When you eat, you are replenishing your body with glucose (aka sugar) which it will then use as its primary energy source for your workout. Fasting, on the other hand, means your body will use stored fat instead [1].
There is also evidence that consistently engaging in fasted exercise can actually lead to molecular adaptations within the body, which are favourable to fat oxidation [2].
In simple terms, it may help rewire how your body uses fat beyond just fasted aerobic exercise.
Does fasted cardio work?
While the impact of fasted cardio workouts on fat stores has been proven, whether or not this leads to actual weight loss and body recomposition is a bit of a trickier question.
Overall, most studies have found that there's not much difference between a fasted workout and a fed workout. At the end of the day, dietary change and the act of working out itself is generally what impacts fat loss and the growth of muscle tissue, whether you eat before exercise or not [1].
That said, there may be other benefits of fasted cardio that see you experiencing great results.
The benefits of fasted cardio
While fasted cardio workouts may not result in greater weight loss than non-fasted cardio workouts, research shows that you will probably still be burning fat at a slightly higher rate.
If you're on a weight loss journey, you might like to try a fasted cardio session here and there and see how it makes you feel.
On top of that, research has also found that fasted workouts can impact blood sugar levels, with one study finding that people with a fasted cardio habit had significantly reduced fasting insulin levels and increased insulin sensitivity, which reduces the risk of diabetes [3].
Are there risks associated with fasted cardio?
A few, but many of them are dependent on the type of exercise you are doing and on just how empty your stomach is.
In particular, the biggest risk is side effects associated with low blood sugar. These side effects often manifest when exerting yourself in high-intensity exercise or a longer endurance aerobic session, and may appear as dizziness, shaking, nausea, spots before the eyes, vomiting or even fainting.
They can also manifest as fatigue, which one study has found is slightly more common in fasted cardio workouts than in non-fasted cardio exercise [3].
Ultimately, the risks are dependent on the type of exercise that you're doing, and for how long you're doing it.
It's important to listen to your body and understand the difference between pushing to the next level, and pushing yourself past your limit, which might not make you feel as good. If you feel lightheaded or nauseous during exercise, slow down, rest and give yourself the chance to recover.
What to eat after a fasted cardio workout
Whether you are coming out of an overnight fast or are engaged in an intermittent fasting diet, what you eat after a fasted cardio workout is crucial to reaping the rewards of your exercise and maintaining a healthy lifestyle.
According to research, the best way to get your digestive system firing and to support body recomposition goals is to opt for fruits, vegetables, beans, lentils, whole grains, lean proteins and healthy fats after exercising [4].
What you eat post-fasted cardio will change depending on the time of day. If you've fasted overnight, ticked your workout off first thing in the morning and are now ready for brekkie, try to focus on a lighter meal that is rich in protein and whole grains, like:
- Boiled eggs with leafy greens and toast
- Porridge with nut butter, fruit and milk
- Smoothies with protein powder
- Greek yoghurt with berries, granola, chia seeds and nuts
If you are an intermittent faster and working out later in the day, why not try:
- Brown rice or quinoa with roast vegetables and a serving of lean meat, egg, tofu or plant-based meat
- A salad-packed sandwich with your favourite protein
- A healthy tuna pasta salad with fresh dill and avocado
If you're on the hunt for a snack, try a piece of fruit, hummus and veggies, or tuna and crackers.
Tackling weight loss head-on
While it's normal to over-indulge at times, if it's becoming commonplace in your routine and is getting hard to shake, Pilot's Metabolic Reset Program takes a science-backed approach to weight loss, with breakthrough treatments combined with health coaching so you can learn healthy habits that will set you up for life, so you can reach a healthy weight and feel your best, physically and mentally.
While fasted cardio might be helpful for weight loss, losing weight generally requires a reduced calorie intake, whether that's through eating less, moving more or a combination of both.
And, it's also important to note that there are biological and psychological factors that impact your ability to lose weight.
If you need a hand kickstarting your health and weight loss journey, Pilot's Metabolic Reset Program helps you tackle excess weight from the inside out to set you up for success.
Over 14% body weight is lost on average by people using one option Pilot can recommend. Learn to control hunger and cravings, target appetite and eat less. Plus, with medical professionals at your fingertips, the program can help rewire your relationship with food to achieve sustainable weight loss.
.svg)
