Genetic Basis of Athletic Capability Flashcards
Define phenotype?
The physical expression of the genes, a consequence of the interaction of the genotype with the physical environment.
What is an athletic phenotype?
Occurs where an ‘athletic genotype’ interacts with appropriate environmental stimuli to produce high-level performance in the chosen physical activity. Ie. nature and nurture.
What do many believe is the most important facet for athletic capability?
Genetic predisposition.
What is closely linked to endurance exercise performance?
VO2max
What is VO2max dependent on?
A number of factors including pulmonary, circulatory and muscle function.
What did Holloszy observe in 1967?
That muscle oxidative enzyme activity adapted in repos e to exercise training. Therefore not only genetic but adaptive also.
What is the difference between HCR and LCR in endurance performance?
HCR is > 300% greater.
What is the difference between skeletal muscle I’m HCR and LCR?
~35% greater in HCR. LCR has ~35% smaller muscle fibre area and a greater capillary density.
How is citrate synthase and b-HAD activity different in HCR and LCR?
~40 % greater in HCR.
How is PFK activity different in HCR vs. LCR?
~30% lower in HCR.
How does VO2max vary in HCR and LCR?
~50% greater in HCR vs LCR
What did LCR show?
Increased mean arterial blood pressure, decreased arterial responsiveness, increased FFA (94%), increase circulating triglycerides (168%), increased circulating insulin (131%) and increases fasting blood glucose (20%). Decreased peroxisome proliferative activated receptor g and co activator 1a. Decreased ATP synthase H-transporting to mitochondria F1 complex.
What is an essential component of Darwin’s concept of the survival of gene pools?
Ability to adapt
What was a key environmental factor present during human evolution?
Exercise
Why could a change in gene-environment interaction help explain?
Modern maladaption to chronic inactivity and chronic diseases.
What is the ACE gene?
An angiotensin converting enzymes which converts Ang1 to Ang2.
What is Ang2?
A potent vasoconstrictor, therefore important I’m regulating blood flow and pressure. It increases bradykinin breakdown.
What is bradykinins role?
Stimulating bold flow, glucose extraction, muscle protein synthesis and aids efficiency.
What is renins role in the angiotensin system?
It is releases from the kidney under conditions of salt, blood volume loss and sympathetic NS. Cleaves angiotensingenin to produce angiotensin 1.
What is a common polymorphism in the ACE gene?
A 287 base sequence insertion or deletion.
What is the deleted allele of ACE associated with?
Greater ACE activity.
What is homozygous inserted (II) ACE associated with?
A greater anabolic and efficiency response to training than those with ID/DD ACE. ‘Better training ability’
What do ACE inhibitors do?
Reduce circulating ACE and therefore have an analogous effect to that of I (insertion) allele expression. They may relate to energy conservation therefore increased efficiency under conditions of reduced nutrient and/or oxygen to flow to the periphery.
What do athletic activity and health show?
Strong correlation which suggest research studies should use active populations as their controls.
Compare selective breeding and trainings effects on athletic ability?
Both can increase but training has a greater effect.
What does exercise do to skeletal muscle mechanical signals?
Converts them into a molecular response.
What are the molecular responses does exercise cause on skeletal muscle?
Increases phosphorylation of TF, increased mRNA synthesis/protein synthesis, inducing a phenotypic adaptation.
Define genotype?
The genetic make-up of an individual.
