The study followed over 380,000 middle-aged men and women.
The participants completed questionnaires, interviews, and physical measurements to determine their baseline health condition along with their physical activity levels and sleep behaviors.
Individuals were excluded from participating in the study if their baseline assessments indicated a history of cardiovascular disease, cancer, sleep apnea, or obesity.
The researchers assessed and summarized physical activity data using metabolic equivalent task minutes. These minutes are roughly equivalent to the number of calories expended per minute of physical activity.
The participants’ health was then tracked until May 2020 or their death, depending on which came first, to assess their risk of dying from any cause, and specifically from cardiovascular disease, coronary heart disease, stroke, and all types of cancer. These are the common issues independently associated with poor sleep and minimal physical activity.
Around 15,500 participants died during the monitoring period.
Approximately 26% of the deaths were from any type of cardiovascular disease; 58% were from all types of cancer; 12% resulted from coronary heart disease; 2% followed a brain bleed stroke; and 3% were from a blood clot stroke.
Those who died during the first 2 years of the study were excluded from the data, as was anyone who died from COVID-19.
The results of the study indicate that the lower a participant’s sleep score, the higher their risk of death from any cause and from all types of cardiovascular disease and blood clot-induced stroke.
Also, those who had poor sleep and no moderate-to-vigorous physical activity had the highest risk of death from any cause, from cardiovascular disease, and from any type of cancer when compared with those having a high-physical-activity-plus-healthy-sleep combination.
People who were younger, female, slimmer, and financially better off, consumed more fruits and vegetables, spent less of their days sitting, had no mental health issues, never smoked, drank less alcohol, and were more physically active tended to have healthier sleep scores.
The researchers acknowledge limitations within the study, including the fact that this was an observational study, which means that it does not establish causality.
The study results also indicate that levels of physical activity at or above the lower threshold recommended by the WHO appeared to eliminate most of the detrimental associations of poor sleep and mortality.
The researchers conclude that emerging evidence supports a synergistic effect of sleep and physical activity on health outcomes.