The University of Sydney researchers found that people with obesity who engage in most of their daily physical activity in the evening experience the greatest health benefits. This conclusion was drawn after studying the habits of 30,000 individuals over an 8-year period. The researchers used wearable device data to track the participants’ physical activity patterns.At any time of the day, whether it’s morning, afternoon, or evening, the researchers found that those who engaged in the majority of their aerobic moderate to vigorous physical activity had the lowest risk of premature death and death from cardiovascular disease. The time between 6pm and midnight seemed to be the most beneficial for this kind of physical activity.
The frequency of moderate to vigorous physical activity in the evening, measured in short bouts of three minutes or more, was found to be more important than the total amount of physical activity done daily.
The study was conducted by researchers from the University’s Charles Perkins Centre.The findings were published in the journal Diabetes Care today.
Dr. Angelo Sabag, a Lecturer in Exercise Physiology at the University of Sydney, stated that around two in three Australians have excess weight or obesity due to various societal factors. This increases their risk of major cardiovascular conditions such as heart attacks, stroke, and premature death.
Dr. Sabag also mentioned that while exercise is not the only solution to the obesity crisis, the research suggests that people who can schedule their physical activity at specific times of the day may be able to reduce some of these health risks.
Prior smaller clinical trials have shown similar results.the type of physical activity, whether it was structured exercise or not. Instead, we specifically looked at continuous aerobic MVPA in bouts of 3 minutes or more. Previous research has suggested a strong connection between this type of activity, glucose control, and reduced risk of cardiovascular disease compared to shorter, non-aerobic bouts.” Joint first author Dr. Matthew Ahmadi emphasized.Dr Ahmadi, a National Heart Foundation postdoctoral research fellow at the Charles Perkins Centre, University of Sydney, explained that the activities tracked in the study ranged from power walking to climbing stairs, as well as structured exercises like running, occupational labor, or even vigorous house cleaning. The study’s findings, although observational, support the original hypothesis based on previous research. This hypothesis suggests that individuals with diabetes or obesity, who already have glucose intolerance in the late evening, may be able to reduce some of that intolerance and its associated effects.complications, from exercising in the evening.
The scientists utilized information from UK Biobank and included 29,836 adults over the age of 40 who were living with obesity, among whom 2,995 individuals were also dealing with Type 2 diabetes.
The participants were divided into morning, afternoon, or evening MVPA groups based on the time when they primarily engaged in their aerobic MVPA, which was measured by a wrist accelerometer worn continuously for 24 hours a day over a period of 7 days at the beginning of the study.
The researchers then connected health information (obtained from the National Health Services and National Records of Scotland) to track the health progress of the participants for 7 years.Over a span of 9 years, researchers documented 1,425 deaths, 3,980 cardiovascular events, and 2,162 microvascular dysfunction events. In order to minimize bias, the researchers took into account factors such as age, gender, smoking, alcohol consumption, fruit and vegetable intake, sedentary behavior, physical activity, education, medication usage, and sleep duration. They also excluded individuals with existing cardiovascular disease and cancer. The researchers believe that the length of the study and additional sensitivity analysis enhance the validity of their results. However, due to the observational nature of the study, they are unable to establish causation.This article discusses the importance of considering potential reverse causation, which is the idea that some participants may have lower aerobic MVPA levels due to an underlying or undiagnosed disease. Professor Emmanuel Stamatakis, the Director of the Mackenzie Wearables Research Hub at the Charles Perkins Centre and senior author on the paper, emphasizes the significance of the sophistication of studies in the wearables field, as they provide valuable insights into the most beneficial activity patterns for health. Wearable device-captured data allows researchers and practitioners to examine physical activity patterns in great detail, marking an exciting time in this field.Professor Stamatakis stated that the research could have a significant impact on healthcare by translating findings into advice. He also mentioned the need for further research to establish causal links, but suggested that the timing of physical activity could be crucial in managing obesity and Type 2 diabetes, as well as preventive healthcare in general. The study was documented in the journal by Angelo Sabag et al.The title of the article is “Association of Moderate to Vigorous Physical Activity with Mortality, Cardiovascular Disease, and Microvascular Disease in Adults with Obesity”. The article was published in Diabetes Care in 2024 with a DOI of 10.2337/dc23-2448.
