Chapter 4 Flashcards
What is general adaptation syndrome?
Adrenal gland responds to noxious stimuli with an alarm response. Adrenal gland adapts over time as the body increases resistance to the stressor.
You generate adaptation by removing stress periodically to allow for recovery and then reapply at a progressive overload.
How does exercise impact tissues via hormones?
Exercise stress impacts hormone response which impacts tissues which impacts tissue response.
What is neuroendocrinology?
Interaction between nervous and endocrine systems
What is neuroendocrine immunology?
Connection between nervous system, endocrine system, and immune system.
What is the interaction between anabolic and catabolic hormones?
Anabolic help promote tissue building, whereas catabolic promote tissue degradation. Anabolic hormones can block the action of catabolic.
What is the lock and key theory?
Hormones only impact cells with appropriate receptor.
What are allosteric binding sites?
Substances other than hormones bind to these which enhance or reduce a cell’s response to a hormone.
What can happen in response to hormone concentrations?
Up or downregulation of receptor number, or altered affinity.
Where do steroid hormones come from?
Gonads or adrenal cortex.
Are steroid hormones fat soluble?
Yes
How do steroid hormones enter cells?
Passive diffusion
How to steroid hormones impact tissue?
Directly alter DNA, code specific proteins.
What are polypeptide hormones made up of?
Chains of amino acids
How to polypeptide hormones enter cells?
NOT fat soluble, use secondary messengers.
How do polypeptide hormones impact cells?
Cascade effect which alters metabolism or DNA/mRNA translation
What is amine hormone?
An amino acid made up of either tyrosine or tryptophan
How doe amines enter cells?
Secondary messengers
Are amines effected by negative feedback loops?
Nah
Are all tissues impacted when a hormone is released via exercise?
NO, only the activated tissues. These may have increased #s or receptors or increased receptor affinity.
How does genetics impact response to hormones at tissues?
Genetic maximums for hypertrophy exist.
Do peripheral concentrations of hormone correlate to effects on cells? Why or why not?
No, high conc may be able to infer high numbers of reactions, but receptor affinity and number impacts too.
What can low hormone peripheral concentrations indicate?
High uptake, high degradation, minimal release.
What are some adaptations that may occur at endocrine glands?
Increased synth, better transport via binding proteins, change in clearance time, increased receptor numbers or affinity, magnitude of impact on nucleus, magnitude of secondary messenger signal.
What is the significance of testosterone?
Primary androgen which impacts skeletal muscle
What is the key for testosterone to impact metabolism?
It’s receptor
What does testosterone do?
Stimulates release of GH, impacts nervous system
When is testosterone highest and lowest?
High in morning, lower at night
How can testosterone be stimulated?
High intensity aerobic or resistance exercise, short rest intervals, mod to high volume, short rests, years of training.
Is the majority of testosterone free in blood?
No only .5-2%, but this can be increased with heavy lifting
What is the impact of age on testosterone levels?
Young men have higher levels
Impact of gender on T levels?
Women have far lower, and do not see spike after exercise.
What is the impact of exercise on receptor levels in the muscles?
Heavy resistance training increases number of receptors
What ultimately leads to the impact of testosterone on muscle tissue?
Metabolic demands via applied stresses.
What is the primary form of GH we focus on?
22 kDa isoform
What are the roles of GH?
- Stimulate protein synthesis
- Increase lypolysis
- Increase use of fatty acids
- Increase availability of glucose and amino acids
- decrease glucose utilization
- Decrease glycogen synthesis
- increase collagen synthesis
- Increase cartilage growth
- Increase renal flow and hypertropy
- Increase immune cell function
What is the main stimulation for increased GH release?
- high H+ concentrations
- High intensity, high duration, short rest training
What is the impact of gender on GH levels?
Higher levels in women due to menstrual cycle, increase with high rep short rest.
How do GH levels get impacted by training?
Resting levels never change, but response of release during exercise increases.
What is the role of IGF?
Regulates GH, impacts protein anabolism
How is IGF released?
GH stim of liver (delayed), or release via mechanical stim to lipid or muscle cells.
Can IGF levels be increased via exercise?
Maybe if low resting levels to start.
What stimulates the medulla of the adrenal gland?
Nervous system, imemdiate impact
What stimulates the cortex of the adrenal gland?
ACTH release from anterior pituitary gland, delayed response.
What is the impact of cortisol?
Catabolic, signals for carb and glycogen metabolism. Inhibits protein synthesis, breaks down proteins, and suppresses glycogenesis and immune system
When is cortisol highest?
Morning, drops over day.
Which type of muscle cell is impacted most by cortisol?
Type II
What stimulates release of cortisol?
High volume, low rest resistance exercise, especially when anaerobic.
What are the acute and chronic effects of cortisol release?
Acutely helps regulate blood glucose and contributes to muscle remodeling.
Chronically may lead to overtraining syndrome, impaired immune function.
What are the two catecholamines?
epinephrine and norepinephrine
What is the role of catecholamines?
Increase force production, contraction rate, release of other hormones.
What leads to release of catecholamines?
High intensity, short rest, heavy resistance training.
How do you prevent adrenal exhaustion?
Vary training
What can increase catecholamine levels?
Increased training experience with heavy resistance may result in increased secretion of catecholamines at max resistance.
