Does "fasted" cardio aid in weight loss? This is the science.

 

The idea of fasted exercise training appears on social media every few years.

The term "fasted training" describes working out first thing in the morning, before breakfast.

Supporters will assert that it is the most effective method for reducing body fat. Critics claim it is a bad idea and will make you put on weight.

Who is correct, and what is supported by the research?

From where did the concept originate?

Proponents claim that accelerated exercise will improve changes in body composition, or the ratio of fat, bone, and lean mass (muscle). They specifically claim that fasting exercise causes fat loss.

Loss of fat mass while growing or retaining lean mass can result in positive changes in body composition. or even by accumulating lean muscle without seeing a decrease in body fat. which could all be viewed as advantageous.

Research demonstrates that exercising after eating has a different effect on metabolism than exercising before eating, which supports the notion that fasted exercise causes such favorable changes in body composition.

When assessed at a single moment in time, aerobic activity while fasting increases the amount of fat you burn as fuel (a process known to researchers as "fat oxidation").

Therefore, assuming that this would result in longer-term fat loss was not a huge leap.

But as my team's 2017 systematic review showed, a fasting exercise training program does not appear to have any lasting effects on body fat reduction.

This disparity between the amount of fat burned as fuel during exercise and long-term increases in body fat has sometimes been misinterpreted.

The body tends to discover ways to adjust, which could explain this seeming paradox. After eating, it appears that fat burning decreases, and those who have engaged in intense activity may find that their overall energy expenditure during the day decreases.

Finding that short-term effects do not necessarily convert into longer-term affects is actually rather prevalent in the field of exercise science.

Regular exercise, for instance, can have a long-term favorable impact on your immune system, but intensive short-term exercise can have a short-term harmful impact.

Eating prior to or following exercise

Your performance during your next workout is likely to improve if you consume a meal high in protein and carbs close before you go out.

But there does not seem to be much of a difference between eating that meal before or after working out.

It is interesting to note that studies have indicated that consuming more protein and increasing the amount of food consumed in the morning may improve body composition and aid in weight loss.

But this time has more to do with when you eat during the day than it does with exercise.

How about athletic performance?

It is rather obvious that eating before working out enhances performance in activities longer than sixty minutes, but it has minimal impact on shorter-duration activities.

The fact that relatively few top athletes advocate for fasting exercise is more proof of this. Nearly 2000 endurance athletes participated in the poll, which revealed that non-professional athletes are more likely than professional athletes to work out while fasting.

How about strength training?

So, when you conduct resistance training (like lifting weights) after fasting versus after eating, do you notice changes in your body composition, muscle size, and strength? Regretfully, there is little and poor quality research.

According to the few information available thus far, it has no effect.

Resistance training twice a week for 12 weeks, either after fasting or after eating, did not affect strength, power, or lean body mass, according to a new randomized controlled research.

Possible disadvantages

When you train too quickly, you may feel extremely hungry afterward, which may cause you to choose less healthful foods.

When attempting to exercise while fasting, some people may even experience nausea and headaches. However, this is not a uniform experience; there are plenty of people on social media who claim that working out while fasting makes them feel fantastic.

In conclusion, there is not a certain victor.

There is no proof that fasting exercise is better for losing weight or improving athletic performance.

But the evidence also does not indicate that it is an issue in many situations (possibly with the exception of elite sports performance).

Therefore, if you are pressed for time and skipping breakfast will enable you to go for a run or work out, then by all means. Do not stress over the outcome too much.

Get some breakfast before you head to the gym, though, if the thought of doing out while hungry makes you want to avoid going. You can be sure that will not interfere with your objectives.

Fitness trends and wellness tips come and go, but exercise is the one that has been proven to be effective time and time again.

The most important thing is just doing it.

Not the time of day, not the specific type of activity, not even the precise quantity, and most definitely not whether you ate or not before working out.