Lactate Threshold: Difference between revisions

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'''Original Editor '''- [[Lucinda hampton|lucinda hampton]]
'''Original Editor '''- [[User:Lucinda hampton|lucinda hampton]]


'''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}}  &nbsp;   
'''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}}  &nbsp;   
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== Introduction ==
== Introduction ==
An important factor in running a fast marathon race is the ability to run at the fastest possible speed without becoming tired. This optimal speed or “threshold” is related to several changes that happen in our body as we exercise, including the build-up of chemicals in the blood. Blood lactate is one such substance that accumulates in the blood during exercise.
[[File:Glycolysis simple.jpg|alt=|thumb|'''Anaerobic lactate production''']]
Lactate threshold defined thus: The level above which pyruvate—an intermediate product of anaerobic metabolism—is produced faster than it can be used aerobically; unused pyruvate splits into lactate (lactic acid) and positively charged hydrogen ions; continued exercise above the lactate, or anaerobic, threshold results in accumulation of these ions—acidosis—causing exhaustion and intramuscular pain<ref>The fee dictionary [https://medical-dictionary.thefreedictionary.com/lactate+threshold lactate Threshold] Available: https://medical-dictionary.thefreedictionary.com/lactate+threshold<nowiki/>(accessed 28.11.2021)</ref>


Many refer to lactate as a metabolic waste product (not really) and blame it for the muscle soreness that can plague us several days after a hard workout (not so, actually inflammation)<ref name=":0">Active [https://www.active.com/triathlon/articles/lactate-threshold-and-v02-max-explained Lactate Threshold and V02 Max Explained] Available: https://www.active.com/triathlon/articles/lactate-threshold-and-v02-max-explained<nowiki/>(accessed 28.11.2021)</ref>.Still, exercise above the lactate threshold is associated with more rapid fatigue and, as such, the speed at lactate threshold is a powerful predictor of endurance performance.
Many refer to lactate as a metabolic waste product (not really) and blame it for the [[Muscle Fatigue|muscle soreness]] that can plague us several days after a hard workout (not so, actually [[Inflammation Acute and Chronic|inflammation]])<ref name=":0">Active [https://www.active.com/triathlon/articles/lactate-threshold-and-v02-max-explained Lactate Threshold and V02 Max Explained] Available: https://www.active.com/triathlon/articles/lactate-threshold-and-v02-max-explained<nowiki/>(accessed 28.11.2021)</ref>. Still, exercise above the lactate threshold is associated with more rapid fatigue and, as such, the speed at lactate threshold is a powerful predictor of endurance performance.


A higher lactate threshold will enable a higher running speed to be sustained without blood lactate accumulating, enabling the running speed to be maintained for an extended period. Elite male and female marathon runners have reported lactate threshold speeds of 18-21km/h<ref>The Conversation Science of champion runners: inside the body of elite endurance athletes Available: https://theconversation.com/science-of-champion-runners-inside-the-body-of-elite-endurance-athletes-146639<nowiki/>(accessed 28.11.2021)</ref>
A higher lactate threshold will enable an endurance activity to be sustained without blood lactate accumulating, enabling the athletes speed to be maintained for an extended period. eg Elite male and female marathon runners have reported lactate threshold speeds of 18-21km/h<ref>The Conversation Science of champion runners: inside the body of elite endurance athletes Available: https://theconversation.com/science-of-champion-runners-inside-the-body-of-elite-endurance-athletes-146639<nowiki/>(accessed 28.11.2021)</ref>


== Sub Heading 2 ==
== Mechanism ==
The lactate threshold is a point during exhaustive, all-out exercise at which lactate builds up in the bloodstream faster than the body can remove it. The only way to make up the difference is to rev up anaerobic glycolysis.
[[File:Athlete.jpeg|right|frameless]]
The lactate threshold is a point during exhaustive, all-out exercise at which lactate builds up in the [[Blood Physiology|bloodstream]] faster than the body can remove it. The only way to make up the difference is to rev up [[Anaerobic Capacity|anaerobic glycolysis]], which occurs in environments environments lacking oxygen.


* Anaerobic glycolysis occurs in oxygen lacking environments. Ultimate end product of anaerobic glycolysis is lactate, which may be harmful to the cell itself, whereas that of aerobic glycolysis is water and carbon dioxide, which are not harmful to cells.
* Anaerobic metabolism produces energy for short, high-intensity bursts of activity, the lactate build-up reaches a threshold where it can no longer be absorbed and accumulates. This point is known as the lactate threshold
* Lactate, which may be harmful to the cell itself [[Aerobic Exercise|(aerobic]] glycolysis is water and carbon dioxide, which are not harmful to cells).
* When the concentration of lactate in the blood starts to climb, our [[Brain Anatomy|brain]] senses this and we start to feel nauseous.<ref name=":0" /><ref name=":1">verywellfit Lactate Threshold Training for Athletes Available: https://www.verywellfit.com/lactate-threshold-training-3120092 (accessed 28.11.2021)</ref>
See Metabolic Acidosis in [[Arterial Blood Gases]]


When the concentration of lactate in the blood starts to climb, our brain senses this and we start to feel nauseous. Within a few minutes we are forced to drop the intensity, ATP demand reduces, Glycolysis is slowed, lactate is cleared from the blood, and all is back to normal.
== Lactate Threshold Values ==
A plot of lactate concentration vs. percentage of V02 max is produced and the lactate threshold is identified as the point of inflection, as demonstrated in the graph<ref name=":0" />


Anaerobic metabolism produces energy for short, high-intensity bursts of activity before the lactate build-up reaches a threshold where it can no longer be absorbed and, therefore, accumulates. This point is known as the lactate threshold.<ref name=":0" />
# Average person: 60% of VO2 max
# Recreational athlete: 65% to 80% of VO2 max
# Elite endurance athlete: 85% to 95% of VO2 max2<ref name=":1" />


Lactate has gotten a bad rap for the past several decades. Many refer to it as a metabolic waste product (not really) and blame it for the muscle soreness that can plague us several days after a hard workout (not so, actually inflammation).<ref>Difference Between Aerobic and Anaerobic Glycolysis Aerobic vs Anaerobic Glycolysis Available:https://www.differencebetween.com/difference-between-aerobic-and-anaerobic-glycolysis/ (accessed 28.11.2021)</ref>
== VO 2 max ==
 
Another way to measure maximum effort is [[VO2 Max|VO2 max]]. VO2 max is the maximum consumption of oxygen that your body can take in and use while exercising. That ability to take in and use oxygen is an indicator of your cardiorespiratory fitness level.<ref name=":1" />
== Sub Heading 3 ==
 
== Resources  ==
*bulleted list
*x
or
 
#numbered list
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== References  ==
== References  ==

Latest revision as of 02:34, 16 August 2022

Original Editor - lucinda hampton

Top Contributors - Lucinda hampton and Kim Jackson  

Introduction[edit | edit source]

Anaerobic lactate production

Lactate threshold defined thus: The level above which pyruvate—an intermediate product of anaerobic metabolism—is produced faster than it can be used aerobically; unused pyruvate splits into lactate (lactic acid) and positively charged hydrogen ions; continued exercise above the lactate, or anaerobic, threshold results in accumulation of these ions—acidosis—causing exhaustion and intramuscular pain[1]

Many refer to lactate as a metabolic waste product (not really) and blame it for the muscle soreness that can plague us several days after a hard workout (not so, actually inflammation)[2]. Still, exercise above the lactate threshold is associated with more rapid fatigue and, as such, the speed at lactate threshold is a powerful predictor of endurance performance.

A higher lactate threshold will enable an endurance activity to be sustained without blood lactate accumulating, enabling the athletes speed to be maintained for an extended period. eg Elite male and female marathon runners have reported lactate threshold speeds of 18-21km/h[3]

Mechanism[edit | edit source]

Athlete.jpeg

The lactate threshold is a point during exhaustive, all-out exercise at which lactate builds up in the bloodstream faster than the body can remove it. The only way to make up the difference is to rev up anaerobic glycolysis, which occurs in environments environments lacking oxygen.

  • Anaerobic metabolism produces energy for short, high-intensity bursts of activity, the lactate build-up reaches a threshold where it can no longer be absorbed and accumulates. This point is known as the lactate threshold
  • Lactate, which may be harmful to the cell itself (aerobic glycolysis is water and carbon dioxide, which are not harmful to cells).
  • When the concentration of lactate in the blood starts to climb, our brain senses this and we start to feel nauseous.[2][4]

See Metabolic Acidosis in Arterial Blood Gases

Lactate Threshold Values[edit | edit source]

A plot of lactate concentration vs. percentage of V02 max is produced and the lactate threshold is identified as the point of inflection, as demonstrated in the graph[2]

  1. Average person: 60% of VO2 max
  2. Recreational athlete: 65% to 80% of VO2 max
  3. Elite endurance athlete: 85% to 95% of VO2 max2[4]

VO 2 max[edit | edit source]

Another way to measure maximum effort is VO2 max. VO2 max is the maximum consumption of oxygen that your body can take in and use while exercising. That ability to take in and use oxygen is an indicator of your cardiorespiratory fitness level.[4]

References[edit | edit source]

  1. The fee dictionary lactate Threshold Available: https://medical-dictionary.thefreedictionary.com/lactate+threshold(accessed 28.11.2021)
  2. 2.0 2.1 2.2 Active Lactate Threshold and V02 Max Explained Available: https://www.active.com/triathlon/articles/lactate-threshold-and-v02-max-explained(accessed 28.11.2021)
  3. The Conversation Science of champion runners: inside the body of elite endurance athletes Available: https://theconversation.com/science-of-champion-runners-inside-the-body-of-elite-endurance-athletes-146639(accessed 28.11.2021)
  4. 4.0 4.1 4.2 verywellfit Lactate Threshold Training for Athletes Available: https://www.verywellfit.com/lactate-threshold-training-3120092 (accessed 28.11.2021)