Study Finds It's Total Exercise – Not Workout Frequency – That Matters Most for Fat Loss

Finding the time to exercise consistently is one of the biggest challenges many of us face, and social media will have you believe that doing anything less than six gym sessions a week will make it impossible to achieve your goals.

But new research suggests otherwise. According to the study, one weekly workout may be just as effective as three for improving body composition and fitness levels – but there's a caveat.

The study, which was published in Nature Communications, set out to measure whether concentrating your exercise into one session a week – as opposed to spreading out that time throughout the week – could influence the rate of fat loss.

Researchers recruited 315 sedentary, overweight adults. Participants were randomly assigned to one of three groups:

• A once weekly HIIT group
• A three times per week HIIT group
• A control group that attended regular health education sessions

Both exercise groups completed the same total training volume of 75 minutes each week over the course of the 16-week intervention. The only difference was how that exercise was distributed. One group performed all 75 minutes in a single session, while the other split it across three workouts.

Researchers assessed body composition before the programme began, after 16 weeks and again 16 weeks later to assess whether any benefits were maintained.

After 16 weeks, both HIIT groups had significantly reduced their total body fat, body fat percentage and waist circumference compared with the control group. Cardiovascular fitness also improved in both exercise groups, with no statistically significant difference between those who trained once a week and those who exercised three times weekly.

On average, participants completing one weekly HIIT session reduced their fat mass by 2.6%, while those exercising three times per week saw a 3.5% reduction. Waist circumference also fell in both groups by around 2cm, indicating that concentrating weekly exercise into a single session can still deliver meaningful benefits.

The researchers conclude that completing the same weekly exercise volume in one session may be a solution for those who struggle to fit multiple workouts into their schedule.

It's worth noting that fat loss ultimately comes down to maintaining a calorie deficit, meaning you burn more calories than you consume. You can achieve that through nutrition, exercise or, ideally, a combination of both. Whether you opt for one longer workout or several shorter sessions is largely down to your schedule and preferences. The best routine is the one you can stick to consistently over the long term.

If there’s one thing Kori Sampson knows, it’s how to optimise your body composition for performance. To tap into his knowledge as an elite athlete and coach, we asked him to create a 4-week plan to help you move faster, recover quicker and keep pushing when the fatigue sets in – all while improving your muscle-to-fat ratio.

Ready to build muscle, burn fat and come out the other side looking, feeling and performing better? Click here to get 14 days of free access to the plan via the Men’s Health app.