A recent study from the School of Public Health at the LKS Faculty of Medicine, the University of Hong Kong (HKUMed), has revealed that exercising just once a week can be as effective for weight loss as working out three times a week. The findings, published in Nature Communications, challenge traditional exercise guidelines and offer a practical alternative for individuals struggling with time constraints.
Obesity: A Global Health Burden
Obesity is a growing health concern worldwide. Excessive fat accumulation, especially around the abdomen, is a chronic condition linked to cardiovascular disease, metabolic disorders, and increased mortality risk. Regular exercise is crucial for managing obesity, but many people find it difficult to maintain a consistent workout routine.
The Potential of Weekend Workouts
Interval training, which alternates between vigorous exercise and lower-intensity recovery periods, has proven effective and time-efficient for reducing total body weight and visceral fat. However, standard recommendations often prescribe interval training three times a week, which may not be feasible for those with busy schedules or limited access to facilities. Previous research has suggested that being a 'weekend warrior'—compressing workouts into one or two days—can be beneficial, but evidence supporting its effectiveness has been limited.
Study Design and Findings
Professor Parco Siu Ming-fai, Head of the Division of Kinesiology at HKUMed, led a rigorous trial involving 315 overweight Chinese adults with central obesity. Participants were divided into three groups: once-weekly interval training, thrice-weekly interval training, or a control group that attended health education sessions. Both training groups completed 75 minutes of interval training per week, either in a single session or split into three. Body fat mass was measured at baseline, 16 weeks, and 32 weeks.
At the 16-week mark, both training groups showed similar reductions in total body fat mass, fat percentage, and waist circumference compared to the control group. Cardiorespiratory fitness also improved equally in both groups, and these benefits were maintained at the 32-week follow-up.
Expert Insights
Professor Siu stated, 'While thrice-weekly interval training remains a commonly recommended approach, our findings show that once-weekly interval training offers similar benefits and represents a practical exercise strategy. For many adults with central obesity who struggle to balance work, study, family, and other commitments, time constraints are a primary barrier to exercising multiple days per week.' He added, 'Instead of relying solely on high-frequency exercise prescriptions, once-weekly interval training can be considered a feasible and effective alternative.'
