- Women may have an advantage over men when it comes to burning fat during exercise, a study suggests.
- Fit people also burn fat more efficiently. You can improve your aerobic fitness through training.
- Burning fat more efficiently is also key for performing well in long workouts, like endurance runs.
Women may have an edge when it comes to burning fat, according to new research.
A pair of studies published this month found that women tend to burn more fat than men during exercise, and athletes with better cardio endurance of all genders burn more fat than their less fit peers.
One study, published in the International Journal of Sport Nutrition and Exercise Metabolism by researchers from the University of Bath, looked at 73 healthy adults ages 19-63 as they participated in a cycling fitness test on an empty stomach.
The researchers found that participants who burned the most fat were those with the best cardio fitness, measured by how much oxygen they could use during a workout (VO2 peak).
But women also consistently burned more fat than men, the study found.
The same group of researchers were able to determine how participants burnt fat for fuel in a second study, published March 6 in Experimental Physiology. They found that specific proteins in muscle tissue helped to break down fat for energy during a workout more efficiently.
However, it's still not clear why the female participants were able to burn more fat than the men.
Being fit can improve your fat-burning ability regardless of gender or lifestyle
Fitter people burned more fat during the exercise test in this study regardless of lifestyle factors such as diet and exercise habits.
Previous research has suggested that more active people tend to burn more fat. That wasn't the case in this study. While exercising more often may make you more likely to have good endurance, the data found that exercise habits didn't seem to be associated with any fat-burning advantage.
It also didn't matter whether participants ate more carbohydrates or more fat in their diets.
These results suggest that if you want to train your body to be a fat-burning machine during exercise, your best bet isn't hours of steady cardio or a special diet. Instead, try improving your overall aerobic endurance.
To do this, consider adding short, intense bursts of work with even shorter rest periods to your workouts. For example, you might sprint for 20 seconds, rest for 10 seconds, and repeat. Do this for six to eight rounds — the pace should be intense enough that you feel exhausted after just a few minutes. This is often known as Tabata style training.
Better fat-burning could give female athletes an edge in endurance sports
How efficiently you burn fat during exercise is important for certain types of athletic performance. That's because fat serves as the body's fuel during periods of low-to-moderate intensity exercise, particularly over long periods of time. During short stints of exercise, the body uses stored carbohydrates to fuel muscles. But this is quickly depleted, at which point the body switches over to its other form of stored energy, fat, to carry you through the rest of the activity.
That makes fat-burning especially valuable for endurance sports, such as marathon or ultra running. And if women are able to do it more efficiently, it could make them more resistant to fatigue during long workouts.
"Ultimately, a greater capacity to burn fat as a fuel has potential benefits for endurance athletes, by delaying the time point when they run out of precious carbohydrate stores," Dr. Javier Gonzalez, senior author of the studies and a human physiologist at the University of Bath, said in a press release.
Women might be more physically resilient than men, too
These findings support previous evidence that women may be better able to stay strong during long workouts, runs, or other physical activity than men.
Women tend to be slightly more resistant to fatigue, have better blood flow in their muscles, and have quicker recovery after exertion than men, according to Greg Nuckols, an exercise science researcher and writer for Stronger By Science, who has studied sex differences in exercise.
"I don't know where the genesis was for this idea that women couldn't train hard or shouldn't exert themselves," Nuckols told Insider.
This better fat-burning could also explain why women tend to have better sensitivity to insulin, a hormone that regulates blood sugar. Insulin sensitivity is a sign of a healthy metabolism, suggesting women are more metabolically flexible than men.