Physical Exercise May Decrease Mortality Risks Associated With Unhealthy Sleep: Study

The study reveals sufficient exercise and healthy sleep contribute to prolonged life expectancy.

Physical activity has been found to counterbalance some of the negative effects of unhealthy sleep on longevity, according to a new study. The study, claiming to be the first one to investigate the combined effects of physical activity and sleep duration on mortality risk, included 92,221 adults aged 40 to 73 years in the UK Biobank cohort, who wore an accelerometer wristband for one week between 2013 and 2015.

"The study showed that increased physical activity levels weakened the mortality risks associated with short or long sleep duration," said study author Jihui Zhang of The Affiliated Brain Hospital of Guangzhou Medical University, China. The work is published in the European Journal of Preventive Cardiology.

Both sufficient exercise and healthy sleep contribute to prolonged life expectancy. However, the interaction between physical activity and sleep duration to promote health is unclear. The study claims objective measurements were made as accelerometer devices were used to record the movements of the participants, instead of relying on participants' self-reported behaviours which is subjective.

Moderate to vigorous physical activity was classified as meeting World Health Organization (WHO) guidelines or not. The scientists found that in people with low volumes of physical activity, short and long sleep was associated with 16 percent and 37 percent raised risks of all-cause death, respectively. Short sleepers with low exercise had a 69 percent elevated risk of death from cardiovascular causes, which disappeared when exercise was increased to moderate or high volumes.

Long sleepers with low exercise levels had a 21 percent increased risk of death due to cancer which disappeared with moderate or high volumes of exercise. In participants with intermediate amounts of exercise, only short sleep was detrimental, with a 41 percent raised likelihood of all-cause death. In those with a high amount of exercise, sleep duration was not linked with the risk of death.

In participants not meeting the WHO exercise recommendations, short and long sleep were associated with 31 percent and 20 percent raised risks of all-cause death, respectively. These risks disappeared in those meeting the WHO advice. For cardiovascular death, short sleepers who failed to meet the advice on the intensity of exercise had a 52 percent elevated risk which disappeared in those achieving the WHO exercise recommendations.

For death from cancer, long sleepers not meeting the WHO exercise advice had a 21 percent raised risk which disappeared in those following the WHO guidance.

"Our findings suggest that health promotion efforts targeting both physical activity and sleep duration may be more effective in preventing or delaying premature death in middle-aged and older adults than focusing on one behaviour alone," said Zhang.