> I don't believe it when research claims X because of personal experience.
That's a horrible way to look at any research conclusion. Have you considered you are possibly oversleeping? 7.5 hours might be a magic number (exactly 5 rem cycles) as opposed to 6.5 which will put you waking up in the middle of a rem cycle. Studies can be faulty for a whole bunch of reasons but dismissing a body of work because your little n=1 experiment didn't sync up with their conclusion is just willful ignorance.
First of all, that has nothing to do with the point I made in my last comment; which is you can't dismiss peer-reviewed research based on personal experience.
Second, that is not how it works. There are varying levels of sleep. Some better than others. When your body doesn't need to go through rem sleep anymore it is sufficiently rested but that doesn't mean you feel like a ray of sunshine and immediately jump out of bed. There are other factors which make a person want to stay in bed longer than they should which leads to shitty non-rem sleep. Too much of this makes you feel groggy.
That's a horrible way to look at any research conclusion. Have you considered you are possibly oversleeping? 7.5 hours might be a magic number (exactly 5 rem cycles) as opposed to 6.5 which will put you waking up in the middle of a rem cycle. Studies can be faulty for a whole bunch of reasons but dismissing a body of work because your little n=1 experiment didn't sync up with their conclusion is just willful ignorance.