Last night I go to bed at 4:30 am...
I was very tired and I try to take nap around 2 am so when I can get up I can do my meditation class, but I couldn't. We was having a very intense training and I can wait to come home and lay down on my armchair. I mean, I usually don't have problems with my training, but I was missed one class and even if you go every day, if you miss one class can be reflected on your physical and mental power...
I prefer to sleep less hours, so I sleep around 6h and if you want to do that you will have to meditate before you go to bed or listening some meditative music and reading something spiritual.