that may be because you actually oversleep. unless you're very young (<20yo), 7h of sleep is likely all you need, and anything less than 6h or more than 8h will leave you tired and lacking energy.
I could set an alarm for 5 am but I predict that I would be even more tired compared to my 10 to 7 schedule.
Alternatively, have some children and your sleep will not be the same for a long long time.
Ryan Carson says he has a 1 year old child, so I doubt he's sleeping through the night. :)