Researchers from the University of Sydney, Australia, have discovered that engaging in physical activity during the evening offers the most significant health benefits for individuals with obesity. This finding emerged from a long-term study tracking 30,000 participants over nearly eight years.
The study utilized data from wearable devices to segment physical activities into morning, afternoon, and evening categories. It revealed that participants who performed most of their moderate to vigorous aerobic exercises—activities that increase heart rate and induce breathlessness—between 6 p.m. and midnight exhibited the lowest risk of premature death and cardiovascular disease.
Interestingly, the study highlighted that the frequency of evening physical activity in sessions lasting at least three minutes was more crucial for health outcomes than the total daily amount of physical activity. This pattern of exercise, measured in short but intense bursts, was deemed particularly beneficial.
The research, published in Diabetes Care, was conducted by the Charles Perkins Centre at the University of Sydney. Dr Angelo Sabag, a lecturer in Exercise Physiology at the university, noted the broader context of obesity in Australia. Approximately two-thirds of the population is overweight or obese, significantly increasing the risk of significant health issues like heart attacks, strokes, and premature death. While exercise alone is not a solution to obesity, timing physical activity effectively can significantly mitigate health risks.
This study is significant due to its scale, the objective measurement of physical activity through wearable technology, and its focus on complex outcomes such as premature death. Dr Matthew Ahmadi, a joint first author and a postdoctoral research fellow at the National Heart Foundation, emphasized that the study did not solely focus on structured exercises but included any vigorous continuous activity sustained for three minutes or more. This could range from power walking to more vigorous tasks like climbing stairs or even active house cleaning.
The research methodology involved data from the UK Biobank, which encompassed 29,836 obese adults over 40, including 2,995 participants with Type 2 diabetes. Participants were grouped based on the most frequent times of aerobic exercise, tracked via a wrist accelerometer, and worn continuously for a week at the start of the study. The health outcomes of these participants were then monitored for almost eight years, during which 1,425 deaths and several cardiovascular and microvascular dysfunction events were recorded.
To ensure the reliability of their findings, the researchers adjusted for various factors, including age, sex, lifestyle habits, total physical activity, and pre-existing health conditions. Despite these precautions, the study’s observational nature means it cannot definitively establish causality, particularly concerning potential reverse causation where lower activity levels could be symptomatic of undiagnosed diseases.
Professor Emmanuel Stamatakis, the Mackenzie Wearables Research Hub Director at the Charles Perkins Centre, underscores the study’s importance. He points out that advancements in wearable technology are significantly enhancing our understanding of how specific activity patterns can influence health. These insights are vital for translating research findings into practical health advice and could impact future guidelines on managing obesity and Type 2 diabetes through targeted physical activity timing.
This study not only underscores the potential health benefits of timing physical activity but also showcases the evolving role of wearable technology in understanding and managing health conditions more effectively. Further research is needed to establish a causal relationship and integrate these findings into broader health care and preventative strategies.
More information: Angelo Sabag et al, Timing of Moderate to Vigorous Physical Activity, Mortality, Cardiovascular Disease, and Microvascular Disease in Adults With Obesity, Diabetes Care. DOI: 10.2337/dc23-2448
Journal information: Diabetes Care Provided by University of Sydney
