Can't reduce my sleep duration through meditation

[Nichts]

Hey guys and girls, 

I am struggling with the following problem:

I don't seem to need any less sleep, even though I meditate two hours every day. I've been practicing vipassana meditation as taught be S.N. Goenka for almost 5 months now. I meditate every day for two hours. One hour in the morning and one in the evening. In the discourses during the retreats, the teacher said that you need less sleep when you meditate daily. He said that if you meditate for two hours a day continuously, you'll need about one hour less sleep. However, this doesn't seem to be the case for me. I still need my eight hours*, no matter how long I meditated the day before. 

This wasn't such a big issue until now because in the last few months I didn't have many responsibilities. But now, uni has started and I've got much less free time. So right now, I am basically spending 10 hours a day doing nothing and I don't know if I  can keep this up.

My sleep quality is pretty good, by the way. I tracked it with the Dreem 2 EEG headband and according to them, my sleep quality is above average in my age group. I also don't drink or do any other kinds of drugs (apart from psychedelics every now and then). I eat very healthy, do a good amount of sports, and try to go to bed at the same time every day (which doesn't always work out). I also use blue-light filters for both my computer and my phone.

So I have no clue why I still need eight hours of sleep. Has anyone here an idea? Could it be because I'm still young (19 y/o) and my brain just needs that amount of sleep to properly develop? Or might I be doing something wrong with my meditation practice?

 

* If I don't have an alarm in the morning, I usually tend wake up naturally after 8 hours

Edited September 15, 2019 by Nichts