I thought this was interesting.....
Lactic acid may NOT be
an indicator of fatigue
In a stunning revelation to exercise physiologists, Dr. George Brooks of the University of California recently reported that lactic acid may have a very different function from that which we has been accustomed for over 80 years. The prevailing theory has been that lactic acid, which is produced under states of anaerobic metabolism, is the limiting factor for continued muscle contraction and the predominant source of fatigue. New research, however, suggests that lactic acid may be a very efficient fuel that is used by the mitochondria in muscle tissue after glucose has been depleted and oxygen remains unavailable.
This finding is important because endurance trained athletes have always been instructed by scientists to exercise below the lactic acid or anaerobic threshold to maximize their use of oxygen for energy. To the contrary, many coaches have ignored this training philosophy and pushed their clients to generate and tolerate increasing amounts of lactic acid. It appears that what they were actually doing is increasing the mitochondrial content of the muscles thus making the athlete more efficient at using lactic acid as energy. This training technique is responsible for allowing athletes to perform longer and to tolerate the highest intensities without fatigue.
So, next time you’re asked to explain the function of lactic acid remember that there is a new theory challenging this long-standing fatigue factor.
The New York Times. May 16, 2006. Kolata, G.
Lactic acid may NOT be
an indicator of fatigue
In a stunning revelation to exercise physiologists, Dr. George Brooks of the University of California recently reported that lactic acid may have a very different function from that which we has been accustomed for over 80 years. The prevailing theory has been that lactic acid, which is produced under states of anaerobic metabolism, is the limiting factor for continued muscle contraction and the predominant source of fatigue. New research, however, suggests that lactic acid may be a very efficient fuel that is used by the mitochondria in muscle tissue after glucose has been depleted and oxygen remains unavailable.
This finding is important because endurance trained athletes have always been instructed by scientists to exercise below the lactic acid or anaerobic threshold to maximize their use of oxygen for energy. To the contrary, many coaches have ignored this training philosophy and pushed their clients to generate and tolerate increasing amounts of lactic acid. It appears that what they were actually doing is increasing the mitochondrial content of the muscles thus making the athlete more efficient at using lactic acid as energy. This training technique is responsible for allowing athletes to perform longer and to tolerate the highest intensities without fatigue.
So, next time you’re asked to explain the function of lactic acid remember that there is a new theory challenging this long-standing fatigue factor.
The New York Times. May 16, 2006. Kolata, G.
