FATIGUE AND
RECOVERY
MECHANISMS
FATIGUE
Exercise induced reduction in the power-generating
capacity of a muscle and an inability to continue
activity is defined as fatigue.
FATIGUE
The onset and rate of fatigue depends on;
- Intermittent or continuous activity
- Slow or fast twitch fibres (slow are more fatigue
resistant)
- Isotonic, isometric or isokinetic muscle
contractions (isometric cause fatigue fastest)
- Intensity and duration of activity
- Level of fitness and training of the athlete
MULTIFACTORIAL FATIGUE
Fatigue is multifactorial, meaning it is usually more
than 1 factor causing the fatigue
Fill in the table using page 147 of your text
Fuel depletion
Metabolic by
products
Neuromuscula
r events
Elevated body
temp
1.
2.
3.
4.
1.
2.
3.
4.
1.
2.
1.
2.
3.
1
LACTIC ACID
Read pages 148-151 of your textbook.
Take notes from page 148/149 and copy down the
lactate shuttle model.
Answer Qs 1-5
OXYGEN DEFICIT
As we start to exercise and move from rest, there
is a period of time which the body’s oxygen
demand exceeds the supply of oxygen from its
system.
Oxygen deficit is the amount by which the oxygen
supply fails to meet oxygen demand.
During this time the body must obtain most of its
ATP anaerobically
STEADY STATE
Steady state is attained when the oxygen supply
equals the oxygen demand.
On an oxygen consumption graph, steady state is
represented by a plateau.
OXYGEN DEBT OR EPOC
At the completion of exercise, the demand for ATP
decreases dramatically. However the amount of
oxygen consumed still remains above amounts
required at resting level. This is called EPOC
(excess post exercise oxygen consumption).
Exhausting high intensity anaerobic exercise results
in a larger oxygen debt than exercise at lower
intensities and work loads
FUEL DEPLETION AND RECOVERY
Predominant energy
system
ATP PC
Anaerobic glycolysis
Aerobic system
Likely causes of fatigue
Types of recovery
ELEVATED BODY TEMPERATURE
- As core temperature rises, sweat rates increase
and blood is redistributed to the skins surface to
maximise evaporative cooling.
- Therefore less blood, oxygen and fuels flow to
working muscles.
- To counteract decreases in blood plasma volumes,
both HR and CO must increase to continue
supplying the same amount of oxygen to working
muscles.
ELEVATED BODY TEMPERATURE
 Sweating
Copy out the did you know on page 160. How
does this relate to chapter 4?
RECOVERY STRATEGIES: REFUELLING
 ATP PC restoration
Passive recovery time
Muscle PC restored
30 seconds
60 seconds
90 seconds
120 seconds
150 seconds
180 seconds
10 minutes
Why would having a high aerobic capacity help with the
restoration of the ATP PC system?
RECOVERY STRATEGIES: REFUELLING
Glucose restoration
Muscles can store greater amounts of CHO in the
hours following exercise, so high GI foods should
be consumed as soon as practically possible to
ensure rapid refuelling.
METABOLIC BY-PRODUCTS: H+ IONS
The more quickly H+ ions can be removed from
muscles, the more quickly performers will recover.
An active recovery;
- maintains higher oxygen levels
- creates ‘muscle pump’
- prevents venous pooling.
- Write a definition for muscle pump and venous
pooling.
RECOVERY STRATEGIES: LOWERING BODY
TEMPERATURE
 Apart from hydration (before, during and after activity),
-
strategies for cooling to maintain optimal core temperature
include;
contrast bathing
cold showers
ice vests
cool rooms
fans/shade/modified clothing
REVIEW QUESTIONS
1.
2.
List two functions of drinks that contain electrolytes
(sports drinks)?
Athletes who perform high intensity efforts as part of
their role in a team sport ( such as soccer, football or
basketball) often undertake an active warm down. Discuss
the effect this has on oxygen debt and how this assists
recovery.
REVIEW QUESTIONS