I'm usually out on my bike at 5:30 for a 9.4 mile ride. I get back to the house a little after 6 then go about the normal morning stuff, get to work and feel energized for the whole morning. I think it does depend upon your sleep cycle, I get up early as a rule. I know for a fact my wife could never ride at 5:30. I think the earlier comment about trying it on a Sat or Sun is a good idea.
Good Luck!