Transcript Lactate Inflection Point & Recovery

LACTATE INFLECTION
POINT & RECOVERY
Week 11
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
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
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
Determining the LT/LIP
VO2 max
• Untrained athlete: LIP
= ~50% VO2 max
• Trained athlete: LIP =
~75-80% VO2max
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
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
Learning Activities
Activity 8, p.77
Newspaper article, p.79