Programming for Physiological Adaptations - Hypertrophy

Question 1

What are the hormones involved in RT?

Answer 1

testosterone, human growth hormone (HGH), cortisol, IGF-1

Question 2

What does testosterone do?

Answer 2

increases protein synthesis and inhibits protein breakdown rates

Question 3

What testosterone changes does RT elicit?

Answer 3

increase in total testosterone in males, females below 30 can have up to 25% increase in free testosterone (above that = no sustained increase)

Question 4

What are some considerations of testosterone’s response to RT?

Answer 4

sequencing of exercise (certain training factors will have a greater influence on testosterone), inverse relationship between intensity and volume, training age (ability to maintain technical execution under higher intensities)

Question 5

What is the testosterone response like in females?

Answer 5

limited concentrations/minimal response to RT, possible chronic adaptation with correct programming (structured, high volume, multi-set) - physiological adaptations to RT may be a result of GH in females

Question 6

What does HGH do?

Answer 6

stimulates the uptake of amino acids into muscles - secreted by pituitary gland during sleep

Question 7

How does RT impact HGH secretion?

Answer 7

causes the secretion of GH isoforms w/ extended half lives, allowing for sustained action on target tissue including skeletal muscle - can also be associated w/ upregulation of IGF-1

Question 8

What factors are focused on to capitalize on the effects of GH release?

Answer 8

moderate-high intensity, high volume, large muscle groups, moderate-low inter-set rest intervals - can get temporary elevation of GH ~30 min post RT

Question 9

Explain cortisol

Answer 9

stress hormone - cellular perception of stress is the same no matter the source

detrimental to muscle development (reduced protein synthesis), acute response greatest w/ high intensity/volume - long rest periods seen to decrease acute response

possible buffered by CHO

Question 10

What are the effects of RT on cortisol?

Answer 10

cortisol lessens w/ progress through a periodized program - suddenly switch exercise = sudden spike in cortisol

Question 11

What is insulin-like growth factor (IGF-1)?

Answer 11

provides main anabolic response for body - increasing rate of protein synthesis (complementary to testosterone) - decelerates proteolysis

Question 12

What effect does RT have on IGF-1?

Answer 12

enhances acute response - facilitate at the muscular level after RT (“revs up” engine to respond positively to hormone)

can intentionally overreach w/ positive effects (most common in endurance) - persistent habitual exposure to RT

Question 13

What are the 3 key take-aways about hormone response to RT?

Answer 13

give considerable thought to training variables, recovery is a weapon, training age and experience play a significant role in prescription (generalized combo of parameters that will cause hypertrophy response)

Question 14

Explain Henneman’s size principle

Answer 14

MUs recruited smallest to largest - load increases = higher order MUs recruited

Question 15

Why is Henneman’s size principle important for hypertrophy?

Answer 15

type 1 fibers - more oxidative, used persistently through ADLs and lower threshold exercises

type 2 fibers - use infrequently, have a lower training status, more responsive to training

want to see the most stimulus recruit the greatest number of muscle fibers possible (want to prescribe parameters so you can see 5 exhausting reps)

Question 16

What are the 5 parameters for muscle hypertrophy?

Answer 16

1) max rep exhaustive - heavier loads, longer rest
2) max set exhaustive - moderate loads, high volume
3) assistant strength - classic BB work (aesthetic)
4) slow tempo exhaustive - high TUT achieved through tempo
5) low load exhaustive - endurance

Question 17

What are the 3 primary mechanisms that affect muscle growth?

Answer 17

1) mechanical tension
2) muscle damage
3) metabolic stress

Question 18

How can mechanical tension drive hypertrophy?

Answer 18

through stretching - actively creating tension through musculature

Question 19

What is the role of external resistance in mechanical tension?

Answer 19

larger resistances = slower contraction velocities = more actin-myosin cross-bridging = increase in the tension that each fiber produces (extent of MU firing frequency influenced by the % external resistance)

may be limited by max ability of strength to build up enough tension to stimulate hypertrophy response (bell curve - looking for sweet spot of about 70-80% range)

Question 20

What are the effects of fatigue on mechanical tension?

Answer 20

increase in fatigue decreases contraction velocity, working muscle fibers unable to produce force needed to do the work (higher threshold MUs being recruited), slower speeds lead to more myo-actin cross-bridging, leading to more mechanical tension on individual fibers

Question 21

What are some of the impacts of metabolic stress?

Answer 21

anaerobic glycolysis for ATP = build-up of lactate, hydrogen ions, and phosphates

muscle ischemia (restriction of blood flow = shortage of oxygen that can increase metabolites)

“choking off” ability of muscle to flush out metabolites, driving hormone response and reiterating cellular damage