December is the darkest month on Ohio's calendar.
A combination of the axial tilt of the planet coupled with a generally cloudy and grey climate means that Columbus in early winter receives about as much sunlight as your average British pub on a moor. We spend the month either anticipating being huddled on one specific couch, eating and watching television, or actually doing it. By the time it's over, our bodies are a bloated, angry reminder not to actually eat an entire pie in one sitting even if that's technically what you're capable of.
Basketball players are not immune to the same lethargy.