Did you know that you can’t ‘make sleep up’? What we mean by this is that if you have several nights where you only get a few hours’ sleep a night, even though you may feel fine, your mental and physical performance will be greatly affected; you have essentially built up a sleep debt.

There’s an interesting sleep debt experiment which involved playing havoc with 48 healthy men and women’s sleep patterns. Before the experiment, each had been getting between 7-8 hours a night sleep on average. Split into 4 groups, the first were made to stay awake for 3 days straight (no napping allowed), the second group were allowed to sleep for 4 hours a night over 2 weeks, the third group were allowed to sleep for 6 hours per night for 2 weeks and the fourth group were allowed 8 hours of sleep for 2 weeks. During the experiment the guinea pig’s participants were tested on their physical and mental performance. 


As you can imagine, the fourth group – the ones who were given the luxury of 8 hours sleep – came out of it just fine; there was no decline in any of their thinking, attention span or motor skills. However, for the poor victims who were receiving 4 or 6 hours sleep a night, their results steadily declined each day. As you can imagine the ones allowed 4 hours sleep a night did the worst but the 6-hour sleep participants weren’t far behind.


And from this experiment, they discovered that sleep debt is cumulative; the less sleep you get over a period of time, the worse your brain function, attention and movements. They discovered that 2 weeks of sleeping on only 6 hours of sleep a night had the same effects on your body as not sleeping for 48 hours. Their attention span, mental and physical performance gave results that were the same as those who hadn’t slept for 2 days.


What’s also interesting is that when asked to score their own abilities, participants felt that their performance worsened for a few days and levelled out or returned to how it was before. This means that we could be going about our days, operating machinery, writing important documents, cooking and driving, without realising that we have sub-optimal brain power, reaction times and physical performance. It’s scary that we could be living in a zombie-like state, believing we’re doing the best we can, when we’re not.


So how much sleep do we need a night before our mental and physical performance starts to wane? Based on several studies, it appears that 7 or 7.5 hours is optimal and that for the majority of adults, 95% require between 7-9 hours’ sleep to function at their best.


The answer to optimal performance? Prioritise sleep! If you are getting less than 7 hours sleep a night, reshuffle your lifestyle and make changes to ensure that you’re getting enough. And if it’s really impossible, then see if you can take a nap during the day – one longer nap at around midday is better than several shorter ones scattered throughout.


If you find it hard to get to sleep or remain asleep, try H7, an innovative sleep patch which stimulates ancient acupressure points to calm the body and relieve anxiety, letting you slip into a good night’s sleep for the whole night.