Research Corner - Q&A Anaerobic, Lactate and Ventilatory Threshold by Michael Boyle | Date Released : 22 May 2008 2 comments Print Close Question: What is the difference between Anaerobic Threshold (AT), Lactate Threshold (LT) and Ventilatory Threshold (VT)? Answer: Anaerobic Threshold (AT) was a term applied to the lactate inflection point, or the point at which the appearance of lactate in the blood accumulates faster that its rate of use. It was once thought (incorrectly) that a lack of sufficient oxygen to muscle shifted energy delivery to anaerobic metabolism, resulting in an increase in lactate production thus causing fatigue. Since lactate does not cause fatigue, nor does it determine anaerobic metabolism, the misnomer anaerobic threshold was rejected as a concept nearly two decades ago. Simply speaking, no “anaerobic” threshold exists. Lactate Threshold (LT) is a more recent and descriptive term for the lactate inflection point described above. Due to the misconception about lactate as the source of fatigue, it was thought that the workload just below lactate accumulation in the blood reflected a maximum sustainable level of performance (typically measured as a one hour time trial). Despite the fact that LT is a more descriptive name for the lactate inflection point than AT, current research suggests that it tends to underestimate time trial performance. Perhaps more important to consider is that there are no fewer than four different established methods of measuring and interpreting LT. Since the exercise science field has not agreed upon a single method, and each method can produce a different set of results for a given athlete, LT has questionable reliability and accuracy in measuring performance. Ventilatory Threshold (VT) describes the inflection point for ventilation during an incremental exercise test. Ventilation increases at about the same rate as oxygen consumption up to about 50 to 70 percent of VO2max (depending on one’s trained level). At this point (just beyond the ventilatory threshold) ventilation increases exponentially. Some researchers have identified two ventilatory thresholds. Although ventilation is not a limiter to performance, there is evidence suggesting that power at VT predicts average power for a 40km time trial. However, similar to LT tests, there are multiple VO2max test designs, and the validity of the results vary by test. More important to measuring performance and training application using a heart rate monitor, VT may not accurately and reliability predict time trial (threshold). Back to top About the author: Michael Boyle Michael Boyle is known internationally for his pioneering work in the field of strength and conditioning and is regarded as one of the top experts in the area for sports performance training. He has made his mark on the industry over the past 30 years with an impressive following of professional athletes, from the US Women’s Olympic teams in soccer and ice hockey to the Boston Bruins, Boston Breakers, New England Revolution, and most recently the Boston Red Sox. His client list over the years reads like a "Who’s Who" of athletic success in New England and across the country including legendary Boston names such as Nomar Garciaparra, Cam Neely, and Ray Bourque. Mike is a featured speaker at numerous strength and conditioning and athletic training clinics across the country and has produced many instructional videos and DVDs in the areas of strength and conditioning, personal training and rehabilitation. In 2012, Michael was selected to become part of the Boston Red Sox coaching staff, acting as a strength and conditioning consultant for the team. Full Author Details Related content Content from Michael Boyle Anaerobic Interval Training Bob Seebohar | Articles Interval Training Michael Boyle | Articles Lactate Threshold Testing Sally Edwards | Articles Anaerobic Threshold Noah Hittner | Articles Training Endurance Athletes Michael Boyle | Articles Joint by Joint Approach to Training Michael Boyle | Articles Hip Bursitis Michael Boyle | Articles Anaerobic, Lactate and Ventilatory Threshold Michael Boyle | Articles Interval Training Michael Boyle | Articles Anterior Knee Pain - Pain Site vs. Pain Source Michael Boyle | Articles Dysfunctional Hip Flexors Michael Boyle | Articles Understanding Hip Flexion Michael Boyle | Articles Core Training and Glute Activation Michael Boyle | Articles Rotary Training Michael Boyle | Articles The Mythology of Hypertrophy Michael Boyle | Articles Developing Single Leg Stability Michael Boyle | Articles Please login to leave a comment Comments (2) Goldstein, Robert | 06 Jul 2011, 14:18 PM Finally an article that is short and sweet that is applicable. Thank You! Reply Marsteller, Michael | 14 Apr 2009, 12:35 PM What is the best way to increase average power for a 40km time trial? Reply Back to top