Exercise Intensity & Endurance Performance Flashcards
What can the lactate profile test be conducted using?
Cycle ergometer or treadmill
What does the lactate profile test entail?
Run for 3 min stages in an incremental test.
GE data is collected throughout.
At end of each stage = HR + blood lactate conc (finger tip blood sample) collected.
Participants continues till exhaustion.
What can be determined from the data collected in the lactate profile test?
Max O2 uptake
Lactate threshold + lactate turn point
Running economy
Running speed at max O2 uptake
Define lactate turnpoint
The 2nd sudden + sustained ⬆️ in blood lactate conc during the incremental test
Define running economy
O2 cost of running a certain distance or speed.
When assessing the running economy, what data should be used?
Data from below the ind. lactate threshold
What is a good running economy seen as?
When athlete uses a lower % of max O2 uptake for a given speed.
Where does the majority of energy come from when exercise is longer than 120s?
Oxidative metabolism
What events come under short endurance?
800m
1500m
What events come under long endurance?
5000m
10000m
Marathon
What are the limitations to short endurance performance?
Power + capacity of anaerobic energy pathways
Ability to tolerate metabolic acidosis
What are the limitations to performance for long endurance events?
Availability of metabolic substrates.
Ability to regulate core body temp
List the physiological factors related to endurance running
Max O2 uptake
Running economy
Fractional utilisation of max O2 uptake
O2 uptake kinetics
Define fractional utilisation of max O2 uptake
% of ind O2 uptake that they’re able to sustain for a given period of Time
What is the fractional utilisation of max O2 uptake linked to?
Lactate accumulation in muscle + blood.
Define O2 uptake kinetics
Rate at which O2 uptake rises at onset of exercise.
What aspect is a crucial determinant of success in endurance events?
Rate of aerobic EE
Compare values of max O2 uptake between trained athletes + sedentary individuals with matched sex and age
50% higher in trained athletes
Amongst all endurance runners, which tend to have the highest Max O2 uptake?
5000m specialists
At a 94-98% VO2 max
Amongst all endurance runners, which tend to have the 2nd highest Max O2 uptake?
800m + 1500m due to increased reliance of anaerobic pathways
Amongst all endurance runners, which tend to have the lowest Max O2 uptake?
Marathon runners
Due to their event being run at a sig. lower intensity + other physiological factors being more important for success.
What speed increase does the step incremental test include?
An ⬆️ of 1km/hr at every 3-min stage
Is running economy more important for the shorter or longer duration endurance events?
More important in the longer duration events.
i.e more important for marathon runners than 800m
When calculating running economy per distance, what must the O2 uptake be measured at?
O2 uptake measured at running speed must be BELOW lactate threshold.
How is running economy per DISTANCE calculated?
O2 uptake (ml/kg/min) / speed (km/min)
What is the average running economy per distance?
200 ml/kg/min
Lower = Good
Higher = Poor
What can good running economy compensate for?
Rel low VO2 max values in elite athletes
What can running speed at VO2 max be useful in doing?
Performance prediction
Training optimisation
How is running speed at VO2 max calculated?
Max O2 uptake / running economy
How is absolute max O2 uptake calculated?
VO2 max x body mass
In what ways is determining lactate profile useful for endurance performance?
Performance potential
Adaptations that have occurred due to training
For how long can exercise around the lactate threshold be sustained for?
In excess of 2 hours
What can provide as a very close estimate of an individuals potential performance time in a marathon?
Running speed at lactate threshold
What athletes tend to have the highest maximal oxygen uptake values?
5,000m specialists
What % of the max 02 uptake does the LT typically occur in elite runners?
80-90%
What race performance can be predicted with remarkable accuracy if the running speed at the lactate threshold is known?
Marathon runner
Why are stages of 3-mins selected for the lactate profile test?
Allows stabilisation of HR, blood lactate + O2 uptake.
What would a rightward shift in the lactate-running speed relationship indicate?
Less blood lactate is being prod for a given running speed
What running events would athletes perform better in subsequent to an improved lactate threshold?
All endurance would be improved, as the LT is an important indicator of general ‘aerobic fitness’.
But most meaningful changes would be in longer distance events that are conducted in close proximity to the LT (i.e marathon).
Why is the lactate turnpoint an important threshold?
Because it separates running speeds for which a SS would be possible in HR, BLac + VO2 below the lactate turn point and those that would not (above instead).
If you exercise even slightly above your LTP + continue to exhaustion you will attain Max values in HR, blood lactate + Vo2.
If you exercise just below your lactate turn point + keep going until exhaustion you won’t attain max values in any of these parameters.
Why is the running speed at VO2 max more useful to the athlete than VO2 max per se?
The running speed at VO2 max allows the combination of running economy (how much oxygen it is costing to run) and the VO2max (the ceiling of aerobic energy transfer). The running speed at VO2 max is useful to the athlete as it will allow performance prediction (in events where the running speed is in close proximity to that which would elicit VO2 max), and it can be used to inform training intensities (there is evidence that VO2 max is significantly improved by training at the running speed at VO2 max).
