If you are keen to look after your body, and your mind, what should be your priority: resting or sleeping? The answer to this question really depends on your circumstances. If you are sleeping between seven to ten hours a night, I’m going to say, “Wake up, sleepy head! It’s time to set your alarm an hour earlier and head to the gym before work.” You will feel more energetic cutting back on sleep and getting all those endorphins going. On the other hand, if you are only getting six hours of sleep a night you probably do not need to physically exert yourself because your health and immune system are probably already stressed.
Professor Greg Roach from the Appleton Institute for Behavioural Science says no one can function well on six or less hours of sleep. “Once you get to six hours a night you’re going to have impaired mental performance, you’re going to be sleeping during the daytime, you’re going to be cranky with your colleagues and family, and in the long-term you’re going to have poorer health outcomes,” said Prof Roach in an interview with Fairfax media.
His key research area is sleep. Other experts also warn that sleep deprivation is bad for your health, and even dangerous if you need to have your wits about you at work.
“When you really, really need to sleep the best thing to do is sleep and sacrifice exercise,” says Tim Olds, a professor of health sciences at the University of South Australia. “The benefits of physical activity are reasonably durable … missing a day or two of physical activity is not so bad.”
Exercise is necessary
But regularly skipping exercise is not a good life habit.
“The general picture is this – physical activity, particularly vigorous physical activity, is incredibly potent,” Prof Olds says. “Even just a few minutes of it will outweigh hours of sitting or half hours of increased sleep.”
Physical activity has an array of benefits for your health and wards off many diseases from diabetes and cardiovascular disease to depression and stress.
“Physical activity is the overwhelmingly strong factor,” Prof Olds says.
Prof Olds research has explored how people balance sleep and exercise needs in their lives and what they are prepared to trade off.
150 minutes sleep = 20 minutes of exercise for stress reduction
He found in terms of stress reduction you would need to sleep two and a half hours to get the same stress release you get from 20 minutes of physical activity.
“For general wellbeing, sleep seems to be the big ticket item but for all the other needs, physical activity gives you more bang for buck.”
Exercise improves sleep quality
Research shows that exercise also improves the quality of sleep, resulting in more slow wave sleep, the deep sleep which helps consolidate memories, and reverse some of the effects of insufficient sleep.
New research by Professor Roach and Professor David Bishop from Victoria University’s Institute of Health and Sport looks at how sleep affects our mitochondrial function.
Mitochondrial function is how muscles convert glucose into a usable energy source – it is how effective our cells are at working as batteries and powering us.
In a group that slept only four hours a night, mitochondrial function was impaired, but daily high intensity interval exercise sessions (comprising of 10 rounds of 60 seconds “going full on” on an exercise bike) reversed the impairment due to sleep loss.
Don’t swap one for another
“The message people should not take away from this is that you should run your sleep down to four hours a day and do 20 mins of exercise and you’ll be fine,” Prof Roach said.
“We found that for that one particular aspect of health, it has nothing to do with how well you do your job, how well your family and team can tolerate you, how likely you are to fall asleep when you’re driving to work or home from work.”
Prof Olds warns against comparing sleep to exercise, saying you can’t trade off one for another.
Professor Emmanuel Stamatakis of the University of Sydney’s School of Public Health is also reluctant to compare exercise and sleep however he has proved that exercise is more effective at reducing premature death than sleep.
“Although physical activity and sleep are different biological states they are both hugely important for health,” Prof Stamatakis said. “We should think of them as two treasured aspects of our lifestyles that are both under threat in modern societies.
“There are many common denominators there, for example excessive screen use/screen addiction and time poverty, both of whom make physical activity and exercise a low priority.”
Sleep encourages exercise
A 2013 study in the Journal of Sleep Medicine, ‘Exercise to Improve Sleep in Insomnia: Exploration of the Bidirectional Effects’, found that people who slept longer each night ended up having longer, higher quality workouts. “Improving sleep may encourage exercise participation,” the researchers concluded.
Another 2013 study in The Journal of Epidemiology, ‘Reallocating Time to Sleep, Sedentary Behaviours, or Active Behaviours’ found that trading 30 minutes of sleep with 30 minutes of moderate or vigorous physical activity could lead to improvements in cardiovascular health.
And don’t forget to eat well
Another important aspect of health is of course eating the right foods and the right amount of food. A healthy diet, exercise and sleep are all necessary to keep our bodies functioning at their best. These three elements feed off of each. If we get enough rest and food we are ready to exercise and exercising gives us a healthy appetite and enough sleep. It is never a good idea to skimp on one in favour of another.
ABOUT PAT MESITI
Pat Mesiti is a best-selling author, coach and educator in the area of personal development. Having built some of Australia’s largest people-driven organisations, Pat understands the power of harnessing human potential. He has shared the stage with some of the world’s great business minds and has sold over millions of copies of his books and materials.