Scientists have stated that middle-aged individuals who do not get enough sleep are less likely to experience the advantages of exercise in terms of protecting against cognitive decline, such as memory and thinking skills.
According to researchers from University College London (UCL), individuals in their 50s and 60s who engage in regular physical activity but sleep less than six hours per night experience a faster decline in cognitive abilities overall.
The study, published in the Lancet Healthy Longevity journal, indicates the importance of sleep in protecting cognitive health as individuals age.
Dr Mikaela Bloomberg, the lead author from UCL Institute of Epidemiology & Health Care, stated, “Our study suggests that getting sufficient sleep may be required for us to get the full cognitive benefits of physical activity.”
The study, utilizing data from the English Longitudinal Study of Ageing (Elsa) consisting of almost 9,000 people aged 50 and over, followed participants for 10 years and assessed their cognitive function using memory and verbal fluency tests.
At the start of the study, individuals who were more physically active had better cognitive function regardless of their sleep duration.
However, this changed over the 10-year period, with physically active individuals who slept less than six hours experiencing a more rapid cognitive decline in their 50s and 60s.
On the other hand, the benefits of exercise on cognitive function were maintained for individuals aged 70 and older, even with short sleep duration.
Co-author Prof Andrew Steptoe from UCL Institute of Epidemiology & Health Care emphasized the need to identify factors that can protect cognitive function in middle and later life.
He also mentioned that interventions should take into consideration sleep habits along with physical activity to maximize long-term cognitive health benefits.