Fatigue and recovery Flashcards
What is fatigue
exercise induced reduction in maximal force and/or power generating capacity of a muscle and an inability to continue the activity.
onset and rate of development is dependent on
- type of activity undertaken - intermittent or continuous
- the muscle fibre type being used - fast or slow twitch
- intensity and duration of the activity
- fitness of the performer
3 fuels stores that can be depleted
-Adenosine triphosphate
- phosphate creatine
- glucogen
3 metabolic biproducts
- inorganic phosphate
- Lactic Acid ( h+)
- adenosine di-phospahte
thermoregulation
- dehydration
- increased core body temperature
- blood flow redistribution
Fuel depletion affects
**Depletion of energy stores dramatically affects the production of ATP- reducing the rate of energy production
Fuel depletion (Creatine phosphate )
- depleted in approximately 10 seconds of high intensity
- glycogen stored in muscles takes over as fuel source resulting in slower ATP rate of production (anaerobic glycolysis or aerobic)
Fuel depletion ( glycogen)
- roughly 90-120 mins ( stored in muscle and liver)
- once depleted, ATP production is limited
- fats contribution increases after depletion of glycogen, decreasing intensity due to greater o2 cost to produce ATP - slowest rate of ATP production
lactate
- Lactate has little effect on muscle contraction (diffuses into blood or oxidised by muscle cells)
hydrogen ions ( H+)
- Accumulation of H+ leads to reduction in pH levels, increasing acidity and leading to acidosis inside the muscle
Lactate inflection point definition ( LIP)
TEXTBOOK KNOW WORD FOR WORD:
the HIGHEST INTENSITY points where there is a balance between lactate production and removal from the blood.
LIP - gerneral info
exercise intensities beyond an individuals LIP- blood lactate concentration increases exponentially
- more rapid fatigue due to more in contribution from anaerobic glycolysis to meet ATP demands
- untrained individuals - arround 55-70%
- trained individuals - 75- 90%
Thermoregulation - dehydration
- water is main component of human body ( 60% of body mass)
- dehydration results in a loss in body mass of 1-2% contributing for elevation in core body temp
dehydration and elevated core temperature
- increased core body temp -> blood flow is redirectd away from the working muscles to the skin for evaporative cooling
- blood plasma loss
Influences fatigue levels by:
- reduced supply of o2 to working muscles
- reducing clearance rates of waste product
- development of hyperthermia
Recovery definition and strategies
Aims to return the body to pre-exercise conditions and reversing the effects of fatigue.
- passive
- active
Passive recovery
- standing still, sitting down and completing little to no movment
-Purpose- replenish PC stores
- low intensity activites
- 50% of the ATP is restored in 20 seconds
- 70% restored in 30 seconds
- 98% after 3 mins
Active recovery
fastest lactate/ hydrogens clearance is achieved by active recovery lower than individuals lactate inflection point after high intensity aerobic exercise
- low intensity post exercsie for 5-10 mins
Active recovery purpose
- reduce HR to resting levels
- replenish oxygen levels in the blood, body fluids and myoglobin
- increase blood flow to the working muscles
- remove higher lactate concentration levels
- accelerate oxidation as this boosts the clearance rate of lactate
How does active recovery reduce metabolic biproducts
-O2 levels are maintained which speeds up the removal of lactate
- creates a muscle pump which increases blood flow elevating the supply of )2 and promoting removal of waste
- prevents venous pooling of blood- mucles pump the blood promoting venous return
