Lecture 2 - Phsyiology of Endurance Athletes Flashcards
What is the time definition of endurance exercise?
What is the physiological based definition of endurance exercise.
Continuous activity beyond 5 mins but less than 4 hours.
Exercise requiring the oxidative energy system.
What does literature suggest the definition of ultra-endurance exercise is?
What distance of running is considered ultra-endurance?
Events exceeding 4-6 hours - could last up to 40 hours across different stages (TdF)
Distances greater than a marathon (26.2 mile +)
What are the considerations for ultra-endurance
athletes?
Long Term Prep (periodisation)
Optimal Movement Rate (race/training pace)
Overtraining Prevention
Psychological Toughness (tough mentally)
Sufficient Nutrition (CHO/Fat/Pro/Hydration)
What factors affect the physiological make up of an endurance athlete?
Muscle capillary density, stroke volume, aerobic enzymes, Type I fibres
What are the 5 physiological factors influencing endurance performance?
Fuel Supply (oxidise fat at submax)
Lactate Threshold
Aerobic Capacity (VO2 max - prerequisite)
Performance VO2 (% sustained)
Economy (if high you lower fuel & O2 consumption)
What are the 3 determinants of race pacing?
VO2 max
Sustainable VO2 max
Lactate Threshold
What is VO2 max?
Amount of O2 an individual can take in and utilise to produce ATP while breathing during heavy exercise
What is the role of VO2 max?
At what percentage do 2.15 marathon runners run of their VO2 max? What does this make their VO2 max to be?
Indicates performance and training statuses.
Marathons ae run at 80-85% of VO2 max which makes marathon runners at 2.15 have a VO2 max of 70-75 ml.kg.min-1
What are the central and peripheral limiting factors of VO2 max?
Central = pulmonary diffusing capacity, max cardiac output and O2 carrying capacity
Peripheral = skeletal muscle characteristics
How is blood lactate controlled?
Lactic Acid is regulated so production/removal results in a steady concentration of 0.5-1.5 mmol/L at rest
What is the mass action effect?
What is lactate accumulation?
Increased lactate caused by increase rate of glycolysis
Glycolysis low at rest, when exercise increases glycolysis gets 30-40x more
What role does blood lactate have in fatigue?
Increased H+ reduces body pH
This inhibits PFK which stops Ca2+ release
This affects muscular contraction
What is lactate threshold?
Why may athletes with the same VO2 max run faster or slower than each other?
First substantial rise in blood lactate compared to resting levels
Running Economy, Velocity @ VO2 max and blood lactate accumulation
What is running economy?
What factors may affect running economy?
Energy demand for a given velocity of submaximal running, by measuring steady state consumption of O2 and RER.
Vary by 30% and is difficult to improve
5% increase in economy = 3.8% in VO2 max
What is the relationship between VO2 max and LT?
Importance of VO2 max and anaerobic energy decreases from 800m to 10k
Importance of RE and LT increase from 800m to 10k
