Week 9 - Effects of aerobic and anaerobic training Flashcards
What are the two key factors to consider when training/performing?
source of energy (ATP-PC system, anaerobic glycolysis, aerobic metabolism) and fibres used for force production (type I, IIa, IIx)
Describe the “Overload” principle of training.
Training effect occurs when a physiological system is exercised at a level beyond which it is normally accustomed
Describe the “Specificity” principles of training.
Training effect is specific to:
* Muscle fibers recruited during exercise.
* Energy system involved (aerobic versus anaerobic).
* Velocity of contraction.
* Type of contraction (eccentric, concentric, isometric).
Describe the “Reversibility” principle of training.
Gains are lost when training ceases.
What are the 3 key principles of training?
1) Overload
2) Specificity
3) Reversibility
What is the main goal of endurance training? What would this training look like?
to increase VO2max
- Large muscles groups trained with dynamic activity.
- 20-60mins, 3x per week, >50% V02max.
What is the average increase in V02max with endurance training? How does this differ with variations in initial V02max?
15-20%
- Smaller increased in individual with high initial V02max. (2-3% - they may require higher exercise training intensities to obtain improvements - >70% V02max)
- Up to 50% in those with low initial V02max.
How much of our V02max is determined by heritability (genetics) in sedentary adults?
50% of V02max in sedentary adults
As well as V02max, what does genetics also play a key role in?
determining the training response - large variations in training adaptations reveal that heritability of training adaptations is approximately 47%.
What is v02max defined by?
Fick equation
V02max = maximal cardiac output X a-vO2 difference
What are differences in VO2max between individuals primarily due to?
differences in SV max - this then influences maximal cardiac output and VO2max
In terms of short duration training (approx. 4 months) what is the dominant factor for exercise-induced improvements in V02max?
increase in SV dominant factor in increasing V02max
In terms of longer duration training (approx. 28 months) what is the dominant factor for exercise-induced improvements in V02max?
Both SV and a-vO2 increase to improve VO2max
How does training increase maximal stroke volume?
Increase preload (End Diastolic Volume)
- Increase plasma volume (days)
- Increase venous return (days)
- Increase ventricular volume (months to years)
Decreased total peripheral resistance (“afterload”)
- Decrease arterial constriction (decrease SNA)
- Increased maximal muscle blood flow with no change in mean arterial pressure
Increased contractility
- Greater force produced with each contraction
Eccentric hypertrophy
chamber size and wall thickness increases in the heart
What happens to cardiac output after training?
Cardiac output can be achieved with fewer beats per min. This is because HR is lower due to an increase in stroke volume.
What does lower resting HR after training lead to?
- Vagal tone increased
- Also allow greater filling time (EDV)
Why may maximum HR fall slightly in the highly endurance trained?
Intrinsic firing rate of SA node decreased?
Following endurance training what happens to post-exercise HR recovery?
its faster
What are the factors responsible for the training-induced increased in arteriovenous O2 difference?
- Muscle blood flow increase
- Decreased SNS vasoconstriction
- Increased diameter and compliance of arteries - Improved ability of muscle fibers to extract and utilize O2 from the blood.
- Increased capillary density: slower blood flow through muscle.
- Increased mitochondrial number/volume.
How does exercise training increase total capacity of vascular bed in the muscle?
i. large conduit artery expansion
ii. increased numbers of resistance vessels
What happens to the transit time of RBCs as a result of training?
- Transit time is increased
overall because with bigger
capillary network, RBCs take
longer to pass through
Endurance training increases the volume of both … and … (80% of total) mitochondria in muscle fibers. What does this result in?
Subsarcolemmal and intermyofibrillar.
This results in improved oxidative capacity and ability to utilize fat as fuel.
During submaximal exercise, explain what happens to blood flow in trained muscles?
Blood flow in trained muscles is LOWER because the A-V difference is greater (better oxygen extraction)