Developing Energy Pathways:  Anaerobic Lactate Energy System

The next energy system for discussion is the Anaerobic Lactate (Glycolytic) Energy System.  When the ATP-CP energy system is depleted the bodies’ only alternative is to use the stored glucose for ATP.  When glucose is broken down through anaerobic conditions, energy is produced. The breakdown of glucose produces pyruvic acid and hydronium ions.  Since oxygen is not available pyruvic acid is converted into lactic acid.  In the past, lactate or lactic acid was thought to be the cause muscle fatigue and soreness along with delayed nerve response in muscles.  However, we now understand the buildup of hydronium ions (H+) to be the cause muscle fatigue and soreness.  Researchers currently recognize lactate as a very dynamic substance. It is a key source of energy for many physical activities, it is formed by only one energy system (anaerobic lactate energy system), and will be utilized by a further energy system (aerobic energy system) in a different part of the body.  

Process of Anaerobic Lactate Energy System:

-         CP stores are depleted

-         Stored glucose is used as fuel in the absence of oxygen

-         Rapid glucose breaks down to form pyruvate acid molecules and hydronium ions

-         If oxygen is present, pyruvate acid molecules enter the mitochondrion to go through
oxidation (aerobic/ slow glycolysis) or if there is a lack of oxygen the pyruvic molecules are converted into lactic acid (anaerobic/ fast glycolysis)

-         The concentration of hydronium ions only increases if there is insufficient oxygen to the active muscles.  When this occurs the environment becomes very acidic causing muscle fatigue and soreness. 

-          During anaerobic glycolysis, the formation of 4 ATP is produced from 1 molecule of glucose.  2 ATP are used in the process, resulting in only 2 ATP molecules of energy from the process of glycolysis

The chart below provides a breakdown of how to develop your anaerobic lactate energy system.  This energy system requires high intensity and short recovery time.