Nancy, good afternoon and a happy Thursday to you. With regard to your question, consider the following. As you are learning in your course text, the anaerobic threshold is the point at which lactic acid starts to accumulates in the muscles and is considered to be somewhere between 85% and 90% of your maximum heart rate. This is approximately 20 beats higher than the aerobic threshold. Your anaerobic threshold can be determined with anaerobic threshold testing. Anaerobic endurance is best developed by using repetition methods of relatively high intensity work with limited recovery. During anaerobic work, involving maximum effort, the body is working so hard that the demands for oxygen and fuel exceed the rate of supply and the muscles have to rely on the stored reserves of fuel. In this case waste products accumulate, the chief one being lactic acid. The muscles, being starved of oxygen, take the body into a state known as oxygen debt. The body's stored fuel soon runs out and activity ceases - painfully. This point is often measured as the lactic threshold or anaerobic threshold or onset of blood lactate accumulation (OBLA). Activity will not be resumed until the lactic acid is removed and the oxygen debt repaid. Fortunately the body can resume limited activity after even only a small proportion of the oxygen debt has been repaid. Since lactic acid is produced the correct term for this pathway is lactic anaerobic energy pathway. The alactic anaerobic pathway is the one in which the body is working anaerobically but without the production of lactic acid. This pathway can exist only so long as the fuel actually stored in the muscle lasts, approximately 4 seconds at maximum effort.
Anaerobic endurance can be sub-divided as follows:
* Short anaerobic - less than 25 seconds (mainly alactic) * Medium anaerobic - 25 seconds to 60 seconds (mainly lactic) * Long anaerobic - 60 seconds to 120 seconds (lactic +aerobic)
