Does Fasted Cardio Work?

Fasted cardio improves body composition, as it uses fat as the main energy substrate. In this article, discover what you should know about it!
Does Fasted Cardio Work?

Last update: 31 July, 2020

Fasted cardio is a strategy many athletes use to improve their body composition. It’s based on the fact that, in the absence of food, the glucose that the body will use as fuel comes from the transformation of fatty acids.

To get these molecules, the body needs to break down the triglycerides that make up fatty tissue. Therefore, this leads to a fat reduction. To learn all the benefits you can get from fasted cardio, read on!

Fat reduction

As we mentioned above, moderate-intensity exercise on an empty stomach improves body composition. An article published in the journal La Tunisie Medicale, which shows the effects of exercising during Ramadan on the body composition of athletes, states this. Normally, both the total mass and fat mass decrease during this period.

However, experts usually recommend people make sure that the exercise they do on an empty stomach doesn’t exceed 60 percent of the maximum intensity they can endure. Although no articles provide solid evidence on fasted cardio and the risk of injury, exercising in these conditions can reduce performance. In fact, dizziness could appear at high intensities, putting the continuity of the activity at risk.

Fasted cardio improves performance

Despite the fact that the exercise must be less intense and that performance may be affected, things change in the long term. Exercising under glycogen depleting conditions stimulates mitochondrial reproduction. Likewise, it improves the body’s ability to oxidize lipids to produce energy.

A woman practicing intermittent fasting.

In fact, fasting protocols are related to the promotion of autophagy, as a study published in the journal Clinics states. This process consists of destroying the body’s unhelpful cells and replacing them with more functional ones.

Thus, training with half-empty nutrient tanks can improve an athlete’s effectiveness when they face the same exercise situation, but with the body loaded with glucose and glycogen.

The health effects of this strategy

On the other hand, and aside from sports performance, fasted cardio can improve health. This technique can reduce insulin resistance, thereby reducing the probability of developing metabolic diseases. In turn, it’s associated with lipid profile improvement, which could have a positive impact on cardiovascular risk.

Furthermore, losing body fat is associated with a better state of health. In fact, people who have a healthy, normal weight are less likely to develop complex conditions in the medium and long term.

In any case, you should do fasted cardio under the supervision of a specialist. This way, you’ll have better control of the intensity and reduce your risk of complications. Also, you need to remember to stay properly hydrated.

Fasted cardio works!

Doing fasted cardio has many health and sports benefits. Regarding physical performance, we should note that it improves an athlete’s effectiveness.

A woman doing cardio.

This situation, which occurs in the medium term, is due to an improvement in lipid oxidation to obtain energy. Mitochondrial reproduction is also important.

Regarding health, reducing body fat is associated with a lower risk of disease. In turn, fasted cardio is able to reduce insulin resistance, which has a positive impact on the individual’s metabolic health.

At the same time, the promotion of autophagy is associated with a lower chance of developing long-term tumor-like problems.

If you haven’t tried this technique yet, it might be a good idea to give it a go. In any case, you should first consult a specialist, as they’ll tell you how to do it safely. Remember that controlling the intensity and hydration are two key factors to avoid complications.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Aloui A., Bklouti H., Souissi N., Chtourou H., Effect of ramadan fasting on body composition in athletes: a systematic review. Tunis Med, 2019. 97 (10): 1087-1094.
  • Antunes F., Garcia Erustes A., Jardim Costa A., Nascimento AC., et al., Autophagy and intermittent fasting: the connection for cáncer therapy? Clinics, 2018.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.