Find yourself running out of energy at roughly the same time day in, day out? Have you tried everything from more coffee and No-Doz to energy bars and splashing cold water on your face? We're going to take a guess and say none of this is working. But, go figure, this is normal. Your body clock has a way of winding itself up and down throughout the day. It needs a little kickstart at times, especially if you're crammed behind a desk for extended periods of time. Here, we cover the most common times of the day your power is sucked away and how to recover and continue on with your productive day. 7 a.m.: The Morning Fog How is it after 8 hours (give or take) of rest and relaxation are you not bouncing off the walls and instead are barely able to form a complete sentence? Blame a little something called sleep inertia. "Sleep inertia can last for up to 2 hours, although it's most severe within the first 10 minutes of waking," says Kenneth Wright, Ph.D., an assistant professor of integrative physiology at the University of Colorado. Wright and his colleagues discovered just how severe in a new study, which shows that the mental impairment caused by sleep inertia is akin to being intoxicated.