block 8- nature vs nuture Flashcards
(16 cards)
Do specific genotypes that provide an athletic advantage?
-studys found that there are a few genes details not importamt
what is the importance of undertsanding genotype for athletic performance
-matching genotypes with effective exercise regimes e.g. children from early age with the gene being put n training programmes to make them elite athletes
-identifying athletic potential
-gene transfer technology e.g. cell doping but we arent their yet
What is angiotensin-converting enzyme (ACE), and what are its functions?
ACE is an enzyme found on the surface of endothelial cells, especially in the lungs and kidneys. It converts angiotensin I into angiotensin II, a potent vasoconstrictor that raises blood pressure. ACE also breaks down bradykinin, a vasodilator. Genetic polymorphisms in the ACE gene can influence ACE levels: the insertion (I) variant is linked to lower ACE levels, while the deletion (D) variant is linked to higher levels.
different ACE levels in different athletes?
-Higher levels of ACE present in people who do strength-based sports such as swimming which leads to a increased level of angiotensin 2= factor of muscle growth = muscle hypertrophy
-lower levels of ACE due to insertion is as a higher frequency in elite distance athletes e.g. runners = lower leaves of angiotensin 2= increased bradykinin = improved vasodilation and more blood flow to tissues
insulin-like growth factor 1(IGF-1)
- IGF-1 is a peptide hormone produced mainly by the liver in response to growth hormone (GH). It acts through the IGF-1 receptor, a receptor tyrosine kinase, to stimulate protein synthesis, cell growth, and hypertrophy.
how does exercise affect IGF-1 ?
exercise promotes IGF-1 release via the release of growth hormone promoted by exercise
-which drives protein synthesis and hypertrophy
-also a neurotrophic, so supports the maintenance and growth of neuronal cells. An example of the link between exercise and mental health
impact of exercise on gene and transcription
Exercise alters gene activity in skeletal muscle, triggering changes in gene expression that support structural and metabolic adaptation (e.g., increased strength, endurance). These effects are influenced not just by DNA sequence but also by gene regulation through epigenetics, which controls when and how genes are turned on or off without altering the DNA itself.
Effect of exercise on epigenetics
When you exercise, it can change methylation patterns and histone modifications in muscle cells.
Growth factors like IGF-1 (insulin-like growth factor 1) also play a role in triggering these changes.
These modifications are mitotically stable — they can persist through cell divisions.
That means your environment (like physical activity) can leave lasting marks on how your genes function.
🧠 Summary:
Exercise doesn’t change your DNA, but it changes how your genes behave through epigenetic mechanisms like:
DNA methylation (usually silences genes)
Histone modification
RNA interference
This helps your body adapt to training by modifying gene expression in muscle and other tissues.
What is PGC-1α and why is it important?
PGC-1α is a key gene regulator activated by exercise. It increases mitochondrial production, energy metabolism, and promotes endurance adaptations in muscle.
How does exercise affect DNA methylation?
Exercise can reduce DNA methylation (hypomethylation) in the promoter regions of key genes like PGC-1α. This leads to increased gene expression, supporting mitochondrial biogenesis and muscle adaptation to endurance training.
What does DNA methylation do to gene expression?
More methylation (especially in promoters) usually turns genes off. Less methylation (hypomethylation) allows genes to be more active.
What is VO₂ max?-CHEAT SHEET UNITS
VO₂ max is the maximum amount of oxygen the body can use during exercise. It’s a key measure of endurance fitness, usually expressed in ml/kg/min.
Does aerobic training improve VO₂ max?
Yes, but people respond differently. Some improve a lot, others only a little — due to genetics.
What did the HERITAGE Family Study show?
It showed that genetics explains a large part of VO₂ max and how much it improves with training. Some people saw big gains, others saw almost none
What is a “fitness gene”?
A fitness gene is a gene that influences physical traits like endurance, strength, or how well you respond to training. Some people have genetic variants that make them naturally better at using oxygen, building muscle, or adapting to exercise.
Which genes affect how much your VO₂ max improves with training?
studies like HERITAGE identified genes (e.g., CKM) linked to energy production, oxygen delivery, and muscle function. 97 genes have been associated with how much VO₂ max increases after endurance training.
