New research from Hong Kong suggests that people seeking to reduce belly fat and improve heart health may not need to exercise several times a week to see results.
A study published in Nature Communications found that interval training performed once weekly can be just as effective as exercising three times a week, provided the total amount of exercise remains the same.
The findings may offer encouragement to people struggling to maintain regular fitness routines due to work, family responsibilities or limited time.
Researchers at the School of Public Health at the University of Hong Kong focused on abdominal obesity, a condition closely linked to cardiovascular disease, metabolic disorders and a higher risk of premature death. Excess fat around the abdomen is considered particularly harmful because it surrounds vital organs and contributes to serious long-term health problems.
The study examined whether fewer but concentrated exercise sessions could deliver similar benefits to more frequent training schedules.
The research team tested a form of exercise known as interval training, which combines short bursts of intense activity with periods of slower movement or rest. In this case, participants alternated brisk walking with slower walking.
Scientists say interval training can burn visceral fat more quickly than steady, continuous exercise because of the repeated shifts in intensity.
The clinical trial ran from September 2021 to September 2024 and involved 315 adults in Hong Kong who had abdominal obesity.
Participants were divided into three groups. One group completed 75 minutes of interval training in a single weekly session. A second group performed the same total of 75 minutes divided into three 25-minute sessions each week. A third control group received only health education and did not participate in the exercise programme.
After 16 weeks, both exercise groups recorded similar improvements.
Researchers found reductions in total body fat, body fat percentage and waist circumference regardless of whether participants exercised once or three times weekly. Cardiorespiratory fitness, which measures how efficiently the heart and lungs function during activity, also improved to nearly the same degree in both groups.
Professor Parco Siu Ming-Fai, head of the Department of Kinesiology at the University of Hong Kong and lead author of the study, said the findings challenge common assumptions about workout frequency.
“Current guidelines usually recommend exercising three times a week, but our study shows that if the total weekly exercise time stays the same, splitting it into fewer, higher-quality sessions produces similar results,” he said.
Researchers believe the results could help shape more flexible exercise recommendations, especially for people who find it difficult to commit to frequent gym visits while still aiming to manage weight and improve overall health.
