Australian scientists from the University of Sydney and the University of Newcastle believe that a high level of physical activity compensates for the negative health effects associated with sleep disorders.
The researchers analyzed UK Biobank data on 380,000 men and women, with an average age of 55. Participants’ health was tracked for 11 years until May 2020. During this time, 15.5 thousand people died, with 4.1 thousand from cardiovascular disease, and 9.1 thousand from cancer.
Weekly physical activity data was measured using MET-minutes. MET is the metabolic equivalent, which is calculated as the ratio of the metabolic rate during physical activity to the resting metabolic rate. A MET minute is equivalent to the number of calories burned per minute of physical activity. For example, 600 MET-minutes per week is equivalent to 150 minutes of moderate-intensity physical activity or 75 minutes of vigorous-intensity physical activity weekly. As part of the study, scientists divided project participants into three groups: high physical activity (1200 or more MET-minutes per week), moderate (600‑1200) and low (from 1 to 600).
The quality of sleep of the subjects was assessed on a scale from 0 to 5, based on division into chronotypes and existing sleep disorders (insomnia, snoring, daytime sleepiness).
The worse a person slept, the higher his cardio risks, that is, the likelihood of dying from any cause and from any cardiovascular disease. However, the risks for poor sleepers varied significantly depending on how physically active they were.
At one end of the scale were people with poor sleep and low physical activity. They were 67% more likely to die from heart and vascular disease, 45% more likely to die from any type of cancer, and 91% more likely to die from lung cancer in particular.
At the same time, people who had poor sleep but were physically active at or above 600 MET-minutes per week successfully offset most of the negative effects of poor sleep leading to increased mortality.
The healthiest sleep and lowest risks were observed among younger participants, women, people with a low body mass index, vegetable and fruit eaters, active, non-smokers and non-drinkers, who also did not work shifts and had regularly high levels of physical activity. .