1. LACTATE INFLECTION POINT & RECOVERY Week 11

2. OBLA Onset of Blood Lactate Accumulation At rest, everyone has lactic acid in their muscles When exercise begins the muscular levels of lactic acid begin to rise The level of hydrogen ions (H+) also rise This is known as OBLA

3. Lactate Threshold Now better known as Lactate Inflection Point (LIP) Lactic acid production is greater than lactic acid removal At exercise intensities beyond the LIP blood lactic acid concentration increases Beyond the lactate threshold/LIP the athlete has to stop or reduce muscle effort Trained athletes can and aim to increase their tolerance to lactic acid accumulation

4. Determining the LT/LIP Scientific testing in labs (eg: AIS) is the best method Some rough estimates are in table 2.3, p.76  Untrained athlete ~60% max HR  Trained athlete ~90% max HR

5. Determining the LT/LIP VO2 max Untrained athlete: LIP = ~50% VO2 max Trained athlete: LIP = ~75-80% VO2max

7. LIP & Fatigue Exercise intensities beyond the LIP are associated with fatigue The greater the exercise intensity above the inflection point, the more rapid the fatigue This fatigue is generally considered to be a consequence of a greater reliance on the anaerobic systems to supply the adenosine triphosphate (ATP) and the resultant accumulation of the by-products of anaerobic metabolism  Lactic acid and hydrogen ions

8. Lactic Acid Removal/Recovery When lactic acid builds up an active recovery is best Keep moving and keep HR slightly elevated This keeps blood flow higher to help break down lactic acid Lactic acid  pyruvic acid  ATP (Kreb’s cycle) Lactic acid is now thought to have some positive effect on performance  When oxygen is available it can help to produce ATP  See fig. 2.17, p.78

9. Learning Activities Activity 8, p.77 Newspaper article, p.79