THE ANAEROBIC GLYCOLYSIS SYSTEM

Question 1

Anaerobic system defition

Answer 1

this system involves more complex chemical reactions that partially breaks down the fuel known as muscle glycogen to release energy via the process of anaerobic glycolysis. This results in the formation of the by-product lactic acid (storage of pyruvic acid).
- This energy system has insufficient oxygen

• This system can resynthesise ATP at a fast rate allowing for the continuation of high-intensity effort. This system is normally used in activities that last between 10 and 75 seconds.
• Anaerobic glycolysis literally means ‘the breakdown of sugar independent of oxygen’.
• ATP is resynthesised from the breakdown of carbohydrates mainly in the form of muscle glycogen (some can come from blood glucose)
• As oxygen is not present, glycogen is not completely broken down and pyruvic acid is formed which then ferments to produce lactate.

Question 2

The anaerobic glycolysis system and exercise

Answer 2

The anaerobic glycolysis system resynthesises ATP at a fast rate and has a higher yield than the ATP–CP system. This increased yield means this system is the major contributor to ATP resynthesis when CP stores deplete (from around 10 seconds of maximal effort). Anaerobic glycolysis is also the main contributor in the following activity types:

• repeated short, high-intensity efforts, when there isn’t enough time for CP stores to fully replenish (e.g. repeat sprint efforts in team sports)
• increasing intensity when already at submaximal levels (e.g. increasing running speed)
• working beyond maximal oxygen uptake (e.g. running uphill or surging to the finish line).

Question 3

recovery

Answer 3

Metabolic by-product accumulation relies on an Active Recovery – Light activity at a low intensity for 5-10 minutes
It allows:
- Increased blood flow to working muscles:
- helps to clear lacate and H+
- Replenish oxygen levels in blood and muscles
- Helps to oxidise Lactate
- Helps to replenish PC stores
- Prevents Venous Pooling

Question 4

lactic acid

Answer 4

Breaks down to Lactate and Hydrogen Ions (H+) very quickly with insufficient oxygen (Anaerobic)
- Lactate levels at the end of long duration activities is not much higher than at rest (fatigue more likely from fuel depletion)
- Therefore, lactate and H+ only really accumulate after relatively short duration, high intensity activities.

Question 5

hydrogen ions

Answer 5

Results in an increase in the acidity within the muscle (muscle acidosis)
- Changes in pH of this magnitude adversely affect:
- energy production
- By slowing the rate of glycolysis – slower ATP production and increased fat usage
- muscle contraction - By interfering with Calcium and the muscles contractile process

Question 6

duration

Answer 6

Predominant system for high intensity exercise up to 60 seconds in duration.

Question 7

Fuel source

Answer 7

glycogen

Question 8

rate of energy for atp resynthesis

Answer 8

Fast, but not as fast as ATP-CP system 1.6 mol/min

Question 9

intensity

Answer 9

High intensity exercise (85 - 95% MHR)

Question 10

limiting factor (fatigue)

Answer 10

Accumulation of metabolic by-product (H + ions)

Question 11

amount of energy produced

Answer 11

Small yield
2-3 ATP per glucose molecule

Question 12

duration

Answer 12

10-75 seconds

Question 13

by-products

Answer 13

Lactate, H + ions