It usually takes me a few days to adjust because my body really follows the sun rising. In the summer, I'm easily up at 5am without an alarm and I feel really refreshed. I'm usually asleep at about 12am. I have no problems going on 4-5 hours of sleep in the summer. When I get up and it's dark out, like today, I'm pretty tired. In the fall, when we set the clocks, I'm pretty happy in the mornings because it's light out when I wake up.
Related pic!
Related pic!