You probably know that we sleep in cycles of roughly 90 minutes, moving through five stages from light to deep sleep and back out again. It turns out that we have an awake cycle as well. When we’re awake, we move from a state of energized alertness progressively into mental and physical fatigue approximately every 90 minutes. At that point, we feel hungry, we lose focus and feel sleepy as our bodies tell us to take a break. The trap we fall into in our drive for productivity is we ignore these signals and turn to caffeine, sugar and our own emergency reserves—the stress hormones that trigger our "fight or flight" state. As a result, we become distracted, jumpy, lose sight of our purpose and become less capable of thinking clearly. We fool ourselves into thinking that we can push through and grind it out...and we expect our teams to follow suit. Sound familiar?...