A new study from researchers at the University of Hong Kong suggests that people with excess belly fat may not need to exercise several times a week to improve their health.
According to the study, doing brisk interval walking just once a week may provide benefits similar to exercising three times weekly, as long as the total exercise time is the same.
The findings come from researchers at the School of Public Health at the LKS Faculty of Medicine of the University of Hong Kong, also known as HKUMed. The study was published in the scientific journal Nature Communications.
The research focused on adults with central obesity, a condition where excess fat builds up around the stomach area. Doctors consider this type of fat especially dangerous because it is strongly linked to health problems such as heart disease, diabetes, high blood pressure, and early death.
Obesity has become one of the world’s biggest health concerns. Many people today spend long hours sitting at desks, using computers, or traveling in cars. Combined with poor diet and stress, this lifestyle has led to rising rates of weight gain and obesity across many countries.
Although doctors strongly recommend regular exercise, many adults struggle to stay active.
One of the most common reasons people give is lack of time. Busy work schedules, family responsibilities, study commitments, and long commutes often make it difficult to exercise several days every week.
This is why researchers wanted to investigate whether a simpler and more convenient exercise routine could still improve health.
The study focused on interval training, which involves alternating between periods of faster, harder exercise and slower recovery periods. In this study, participants performed brisk interval walking. This type of exercise raises the heart rate for short periods before slowing down again.
Previous research has already shown that interval training can improve fitness and help reduce body fat more efficiently than steady, moderate exercise. However, traditional exercise guidelines often recommend doing interval training at least three times per week.
Professor Parco Siu Ming-fai, who led the research team and heads the Division of Kinesiology at HKUMed, said the researchers wanted to test whether people could receive similar benefits from doing the exercise only once weekly.
The research took place in Hong Kong between September 2021 and September 2024. A total of 315 Chinese adults aged 18 and older joined the study. All participants were overweight and had central obesity.
The volunteers were divided into three groups. One group completed all 75 minutes of interval walking in a single weekly session.
Another group divided the same total exercise time into three separate sessions during the week. The third group acted as a control group and attended health education sessions every two weeks instead of doing interval training.
Researchers carefully measured body fat, body fat percentage, waist size, and fitness levels at the beginning of the study, after 16 weeks, and again after 32 weeks.
The results were encouraging. Both exercise groups showed similar improvements after 16 weeks. People in both the once-weekly and three-times-weekly exercise groups reduced body fat, lowered their waist measurements, and improved their cardiorespiratory fitness compared with the control group.
Cardiorespiratory fitness refers to how well the heart and lungs supply oxygen to the body during exercise. Higher fitness levels are linked to lower risks of heart disease and better overall health.
Importantly, the once-weekly group achieved these benefits while exercising less frequently. This suggests that people who cannot fit multiple workouts into their weekly schedules may still improve their health with one longer session.
Professor Siu said the findings provide strong scientific evidence that once-weekly interval training may be a realistic alternative for adults who struggle to maintain traditional exercise schedules.
The study also supports the growing idea of the “weekend warrior” approach to exercise. This term describes people who complete most or all of their weekly physical activity during one or two days instead of spreading it throughout the week.
Earlier studies suggested that weekend warriors could still gain important health benefits, but scientific evidence specifically involving interval training had been limited.
The new research helps fill that gap and may influence future exercise recommendations for people with obesity.
The study appears well designed because it included a large number of participants and followed them over many months. Researchers also used advanced body scanning methods to measure body fat accurately.
However, there are still some limitations. The participants were all Chinese adults with central obesity, so researchers do not yet know whether the same results would appear in other populations or age groups. Scientists also need longer studies to determine whether the benefits continue over many years.
Still, the findings are encouraging for people who feel discouraged by strict exercise recommendations. Many adults believe they must exercise almost every day to improve their health, which can feel overwhelming and unrealistic.
This study suggests that even people with very busy lives may still gain meaningful health benefits from one well-planned exercise session each week. For many adults struggling with obesity, that message could make exercise feel much more achievable.
If you care about weight loss, please read studies that hop extract could reduce belly fat in overweight people, and early time-restricted eating could help lose weight .
For more health information, please see recent studies that Mediterranean diet can reduce belly fat much better, and Keto diet could help control body weight and blood sugar in diabetes.
Source: The University of Hong Kong.
