You may have this idea that you’re not getting enough sleep. Chances are, you’re not. There’s a big difference on our performance when we have adequate sleep every night versus when we don’t have enough. So, how much sleep do we actually need? About some 15 years ago there was this theory that if you get about 4 to 5 hours of sleep a night then your body will just adapt and the brain can still be able to perform well. But that was because the studies conducted then were on participants who were only monitored during sleeping time at night. They were able to go home by morning. They could also have taken a nap during daytime or they could have been drinking coffee.