In the quest for effective weight loss strategies, a recent study suggests that the optimal time to engage in daily moderate to vigorous physical activity is between the hours of 7 and 9 in the morning. This illuminating research, published in Obesity, the premier magazine of The Obesity Society (TOS), explores the diurnal pattern of physical activity and its impact on obesity.
Dr. Tongyu Ma, an assistant professor in the Health Sciences Department at Franklin Pierce University, New Hampshire, and the Department of Rehabilitation Sciences at The Hong Kong Polytechnic University, led this groundbreaking study. Previous research has primarily focused on the frequency, intensity, and duration of physical activity, with little attention given to the diurnal pattern of human movement and its association with obesity.
The study utilized data from the National Health and Nutrition Examination Survey, specifically the 2003–2004 and 2005–2006 cycles conducted by the Centers for Disease Control and Prevention, which included accelerometer-measured physical activity. In total, 5,285 participants were cross-sectionally analyzed.
The diurnal pattern of objectively measured moderate to vigorous physical activity was categorized into three groups: morning, mid-day, and evening, using K-means clustering analysis—an established algorithm for identifying hidden patterns in data sets.
The results revealed a robust linear relationship between morning physical activity and reduced obesity, while the connection weakened in the midday and evening groups. Those who met the recommended physical activity guidelines in the morning cluster exhibited lower body mass index and waist circumference compared to the other clusters. Additionally, participants in the morning group reported healthier dietary habits and lower daily energy intake per unit of body weight.
Despite spending more time in sedentary behavior, individuals in the morning cluster maintained favorable outcomes in terms of body mass index and waist circumference. Interestingly, the morning cluster consisted of older participants, primarily non-Hispanic White individuals with higher education levels and a lower prevalence of tobacco and alcohol use.
Dr. Rebecca Krukowski, a clinical psychologist specializing in behavioral weight management, emphasized the significance of this research, noting the common advice to schedule morning exercise before daily distractions. However, she also highlighted the limitations of the study, such as its cross-sectional nature, which does not account for potential differences in schedules and lifestyles between morning and non-morning exercisers.
While the study sheds light on the potential benefits of morning physical activity for weight management, further research is needed to explore the underlying factors that contribute to these findings.