This new study sought to find the ideal time of day to participate in moderate-to-vigorous physical activity (MVPA) to control weight, as obesity is linked to chronic illnesses and early death.
Physical activity is recognized to help reduce weight, control weight, and improve health, but the ideal time of day to exercise has been contested, which is why the researchers did this study.
The researchers undertook a cross-sectional examination of 5,285 people in the 2003–2006 National Health and Nutrition Examination Survey to investigate how workout duration affects weight and belly fat reduction.
Three clusters were formed based on when participants exercised: early morning (7:00 a.m. to 9:00 a.m.), noon (9:00 a.m. to 4:00 p.m.), and evening. MVPA and obesity were examined.
The outcome? Early morning exercise reduced waist circumference and belly fat the most of the three groups. Morning workout participants had an average waist measurement of 91.5 cm (36 inches), compared to 95.8 and 95.0 for noon and evening workouts.
"The main link to waist circumference and belly fat is visceral fat, the dangerous inflammatory fat that gets packed around your organs," explains functional medicine pioneer and bestselling author Dr. Stacie Stephenson. "Visceral fat is the most dangerous, but it burns off quickest when you diet and exercise.
The study did not investigate why morning workouts are better for belly fat removal, although there are several ideas.
Stephenson thinks one explanation is that you're more inclined to exercise in the morning than later in the day. "When you workout first, you're less likely to make excuses for running out of time, being tired, having too much to do, etc.
Working exercise in the morning might also boost your mood because you're starting the day healthy. It "energizes you and you might eat less and make better lifestyle choices," adds Stephenson. "Daily repetition builds up. You may experience major life changes."