WOD Doc: Muscular / Metabolic Fatigue vs. Central Nervous System Fatigue

Episode 100: put on your thinking caps, especially to understand CNS Fatigue.

Physical Fatigue: is the decline in force of the muscle to do work. A muscle that utilizes up its nutrient resources has nothing to draw from. This is muscular fatigue. In the context of a WOD as performance declines, you enter metabolic fatigue.

CNS Fatigue: here it gets tricky. The nerve impulses that normally cause the muscle to fire has a threshold that must be met in order for the muscle to contract. What begins to happen is as the nervous system gets ‘physically taxed’, it’s rate of recovery is not like the our musculature. This is why you can max lift for a PR one day, but will be unable to do it successively day after day. This is why on the biggest stage like the Crossfit Games or the Olympics, you tread the fine line of reaching peak performance at the right time.