A new study published in The American Journal of Physiology – Endocrinology and Metabolism turns traditional thinking about lactic acid, a.k.a. lactate, on its head. Athletes and their coaches have long fought to reduce the amount of lactic acid found in the blood, believing it to be only a toxin produced by tired muscles. As it turns out, lactate is actually a key source of energy for muscles and the heart, provided that your cells have enough mitochondria to process it.
The heart even prefers lactate as a fuel, Brooks found.
Mitochondria are the inter-cellular mechanisms that produce energy; the more of them you have, the more efficiently you’ll be able to oxidize lactate into energy. This study apparently links the process of anaerobic metabolism with aerobic metabolism – lactate is produced in the former, and burned off in the latter.
If I understand the results correctly, the implication of this study is that atheletes should be striving to maximize their mitochondria concentration instead of focusing on lactate reduction. Producing more lactate during training will encourage the body to produce more mitochondria to process it. So a focus on high-intensity workouts, followed by rest/recovery periods, would probably be optimal for acheiving maximum training benefit.
