During sleep, neuronal structures are organized and learning processes are firmly anchored. But even though sleep is so important for our learning and although we spend about one third of our life sleeping, its importance for optimal performance is largely underestimated. This is particularly surprising for two reasons. Firstly, athletes sleep less and tend to sleep worse [1]. Secondly, there are many research results that have found very solid associations between sleep and performance [2]. For example, it has been known for 20 years that sleep deprivation makes people “drunk”: the reaction time after 17 and 22 hours of wakefulness corresponds roughly to the reaction time of 0.5 and 1.0 per mille blood alcohol level [3]. When you consider that some sport competitions are not held until late in the evening, this example alone makes it clear that elite athletes should take their sleep hygiene [4] (the behavior surrounding sleep) very seriously and should continuously optimize it.