Regular exercise doesn’t work in the long-term without the right sleep schedule, a new study has suggested. 

According to the study, people who were more physically active but regularly slept for less than six hours had “faster cognitive decline overall” - putting them at the same physical level as people who did not exercise after 10 years. 

Lead author Dr Mikaela Bloomberg told The Pat Kenny Show good exercise must be complemented by the right amount of sleep. 

Dr Bloomberg studied 8,900 people over 10 years – and found many people liked to exaggerate their level of exercise. 

“We found the participants in our cohort did tend to over report their physical activity,” she said. “But because everybody pretends to over report... it's doesn't really impact the results. 

“As for sort of self-reported sleep duration, it is a bit challenging to kind of know for sure how off how long you slept each night. 

“We do see that self-reported sleep duration is associated with a lot of clinical outcomes, things like wellbeing, dementia, cardiovascular issues.” 

Women in a yoga workout exercise together in a gym. Image: Ammentorp Photography / Alamy Stock Photo

While your sleep schedule can’t fully determine conditions such as dementia, the right sleep habits never hurt. 

“It might delay the age when you reach that threshold for cognitive impairment where it starts to seriously impact your quality of life,” Dr Bloomberg said. 

As we get physically older, the right sleep habits – not just including duration - can prevent someone from aging faster cognitively. 

“It was particularly in the middle-aged that we saw this effect of faster cognitive decline with the high physical activity and the short sleep duration,” Dr Bloomberg said. 

“Sleep duration is just one measure of sleep quality - as we age, sleep becomes more fragmented, so sleep duration alone just might not be as good of a measure for cognitive function as we age.” 

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