Just one 75-minute session of brisk interval walking per week can help reduce body fat and improve physical fitness almost as effectively as three workouts per week.

The Study and Its Participants

Between September 2021 and September 2024, a randomized study was conducted in Hong Kong involving 315 adult Chinese participants aged 18 and older, all with excess weight and central obesity. The participants were divided into three groups: one group performed interval training once a week, the second group trained three times a week, and the third served as the control group.

Methodology and Measurements

Both groups engaged in physical activity completed a total of 75 minutes of interval training per week: one group did it in a single session, while the other split the time across three workouts. The control group attended 2.5-hour health education sessions every two weeks for four months. Body fat was measured using dual-energy X-ray absorptiometry at three points: before the program, after 16 weeks, and after 32 weeks.

Results

After 16 weeks, both interval training groups showed similar improvements: reductions in total body fat, body fat percentage, and waist circumference. There was also an improvement in cardiorespiratory endurance compared to the control group. The results were comparable to those observed in participants who trained three times a week, which aligns with traditional physical activity recommendations.

Significance for Obesity Control

Obesity is a chronic condition associated with excessive fat accumulation, especially in the abdominal area, increasing the risk of cardiovascular diseases, metabolic disorders, and premature death. Physical activity plays a key role in managing obesity and offers a wide range of health benefits. However, many people, especially those with obesity, find it difficult to maintain regular exercise due to lack of time.

Features of Interval Training

Interval training alternates periods of high intensity with phases of active recovery at lower intensity. Research shows that this approach is more effective at reducing overall and visceral fat compared to continuous moderate-intensity exercise. Most guidelines recommend three workouts per week, but such a schedule can be challenging for people with busy work lives, family responsibilities, or limited access to gyms.

A Practical Alternative

The study results confirm that interval training once a week can be an effective and practical option for adults with central obesity, especially for those who cannot find time for multiple weekly workouts. This approach can be considered an alternative to traditional physical activity recommendations for reducing body fat and improving fitness.