Obesity is a major health concern that increases the risk of various medical conditions such as type 2 diabetes, cardiovascular disease, and cancer. Researchers at the University of Sydney conducted a study to determine the best time of day for physical activity to aid in weight loss for people with obesity. The study, published in the journal Diabetes Care, found that getting the majority of daily physical activity in the evening offers the most health benefits for individuals with obesity. The study included data from almost 30,000 people over the age of 40, all of whom had obesity, and about 3,000 of whom had type 2 diabetes. The researchers found that people who engaged in most of their aerobic moderate to vigorous physical activity between 6 p.m. and midnight had the lowest risk of premature death and death from cardiovascular disease.
The study focused on continuous aerobic moderate to vigorous physical activity, which included activities such as walking, dancing, mowing the lawn, lifting weights, jogging, running, hiking, and playing sports. Participants wore wearable devices to track their physical activity levels in the mornings, afternoons, and evenings over an eight-year period. The researchers found that the frequency of performing moderate to vigorous physical activity in the evening, as measured in spurts of at least three minutes, was more important than the total amount of physical activity done throughout the day. This suggests that engaging in multiple short bouts of physical activity throughout the day may be more beneficial than accumulating all physical activity in one block.
The lead author of the study, Angelo Sabag, explained that the improved cardiometabolic regulation associated with evening physical activity may be partly responsible for the health benefits observed in the study. This theory is supported by recent clinical studies that show exercising in the evening leads to greater improvements in blood pressure. Researchers believe that exercising at night can offset the body’s natural insulin resistance, which is a key driver of obesity-related complications. Sabag further emphasized that physical activity, whether structured exercise or incidental, offers significant health benefits and can improve various cardiometabolic outcomes. Engagement in physical activity, particularly in short bouts lasting at least three minutes, can lead to better blood glucose control, reducing the risk of cardiovascular disease and other associated complications.
While the study suggests that evening exercise may have unique benefits for individuals with obesity, it is essential to approach these findings with caution. Additional research is needed to verify these findings across a wider range of populations and understand the underlying mechanisms. The broader consensus remains that engaging in regular physical activity, regardless of the time of day, is crucial for overall health. Individuals who are limited to morning or afternoon workouts should not be alarmed by the findings of this study alone. Further investigations are necessary to determine if the timing of physical activity significantly impacts health outcomes before any revisions to public health advice can be made.
