Summary: High-intensity interval training (HIIT) burns more fat than aerobic exercise, according to a new study.
Font: Victoria University of Melbourne
“If that stubborn body fat just won’t go away, consider adding high-intensity interval training, or HIIT, to your exercise routine,” says Professor Zeljko Pedisic of the University of Victoria, Melbourne.
HIIT increases fat burning more than aerobic exercise, according to a study published in the British Journal of Sports Medicine.
How was the study carried out?
The study authors combined the results of 18 controlled intervention trials on the effects of HIIT on the rate of fat burning during exercise.
Intervention trials included a total of 511 adult participants performing supervised HIIT, moderate-intensity aerobic exercise, or a no-exercise control group.
The duration of the exercise interventions ranged from two to 14 weeks. In almost all studies, participants participated in three HIIT sessions per week.
What are the key findings?
A few HIIT sessions a week will turn your body into a fat-burning “machine.” HIIT will cause you to start burning more fat not only during HIIT sessions, but also during other types of physical activity, such as brisk walking, swimming, and playing sports.
Fat metabolism will improve after just four weeks of HIIT and will continue to improve over time.
After 12 weeks of HIIT, each minute of physical activity is expected to burn an additional 0.13 grams of fat. For someone who engages in 150 minutes of physical activity per week, this could lead to approximately 10kg of additional fat burning in a decade.
Overweight people can expect greater increases in fat burning, compared to “normal” weight people.
While people could also improve fat metabolism by engaging in aerobic exercise (for example, jogging), this would require a much larger time commitment and the improvements would be smaller.
Why is this important?
These findings may help more than two billion overweight people (external link) in the world improve their fat metabolism and reduce weight.
They can also help billions of people prevent unwanted weight gain over time.
“According to the recent Global Fitness Trends Survey (external link), HIIT is among the most popular types of training. If you’re not already doing it, maybe you should give it a try,” Professor Pedisic concludes.
About this exercise research news
Author: press office
Font: Victoria University of Melbourne
Contact: Press Office – Victoria Melbourne University
Image: The image is in the public domain.
original research: Closed access.
“Effects of high-intensity interval training (HIIT) and sprint interval training (SIT) on fat oxidation during exercise: a systematic review and meta-analysis.” by Muhammed M Atakan et al. British Journal of Sports Medicine
Summary
Effects of high-intensity interval training (HIIT) and sprint interval training (SIT) on fat oxidation during exercise: a systematic review and meta-analysis.
Goal
See also
To investigate the effects of high intensity interval training (HIIT) and sprint interval training (SIT) on fat oxidation during exercise (FatOx) and how they compare with the effects of moderate intensity continuous training (MICT).
Design
Systematic review and meta-analysis.
data sources
Academic Search Ultimate, CINAHL, Digital Theses and Dissertations Network Library, Open Access Theses and Dissertations, OpenDissertations, PubMed/MEDLINE, Scopus, SPORTDiscus, and Web of Science.
Eligibility criteria for study selection
Studies that used a between-group design, with adult participants who were not trained athletes, and that evaluated the effects of HIIT or SIT on FatOx (versus no exercise or MICT) were included.
Results
Eighteen studies of fair to good quality were included; nine compared HIIT or SIT with no exercise and eleven compared HIIT or SIT with MICT. A significant combined effect of these types of interval training was found on FatOx (mean difference in g/min (MD) = 0.08, 95% confidence interval (CI) 0.04 to 0.12; p<0.001). Significant effects were found for exercise regimens lasting ≥4 weeks, increasing with each additional week of training (β=0.01; 95% CI 0.00 to 0.02; p=0.003). HIIT and/or SIT were slightly more effective than MICT (MD=0.03, 95% CI 0.01 to 0.05; p=0.005). Effects on FatOx were greater among overweight/obese people.
conclusion
Participating in HIIT or SIT may enhance FatOx, with greater effects expected for longer training regimens and overweight/obese individuals. While some effects seem small, they may be important in holistic approaches to improving metabolic health and managing obesity.
