Flashcards in Hypertrophy 4 Deck (17)
What did Phillips et al (1997) state about breakdown and synthesis??
That FBR and FSR are positively correlated (r= )
In the absence of nutrition, breakdown is more favourable
What did Wolfe et al (2001) state about protein breakdown and its importance??
Believed that MPB was important for the provision of AA for new MPS, gluconeogenesis and energy production.
Useful for the preservation of the intracellular AA pool.
What did De Boer et al (2007) find??
They had young men undergo 6 weeks of unilateral leg immobilization.
The recovered the 5% loss of quad CSA after 6 weeks of retraining.
MAFbx and E3 sig increased following 6wk of immobilisation
MRNA expression of mURF1 and MAFbx was reduced 24h after cast removal.
What did Porter et al (2013) find when looking at burns patients?
Found that when fed AA, phe net balance was significantly higher , both acutely and after 6 months compared to basal in burns.
Discuss Williams et al (2012) looking at cancer patients??
In cancer patients, control fed and post op fed had significantly higher FSR. The C2 proteasome was significantly higher for MRNA fold compared to basal. MURF-1 increased but this was not significant.
Regarding extreme catabolic conditions, what two conditions don't lead to an increased UPS??
Muscular dystrophy and Cushing syndrome
Durham et al (2004) measured limb PS and PB using a 2 + 3-pool AV model, what did they find??
No changes in Leg protein breakdown during a bout of resistance exercise
Discuss Maclean et al (1993)??
Used net efflux of AA from the leg during cycling to represent leg breakdown - but this isn't ideal as as it could indicate other changes in protein kinetics also.
Found that exercise with BCAA was significantly lower than exercise with water for EAA and BCAA release
What did Hulston et al (2011) suggest??
Showed during a 3h cycle, leg protein breakdown was elevated and net balance became more negative in CHO alone compared to CHO and PRO.
Discuss Phillips et al (1997)??
Informs us there's no doubt that MPB is elevated following RE.
An increase in MPS exceeds the increase in MPB, therefore RE alone is actually anabolic.
Also stated that the increase in FBR may be more short lived than the increase in FSR.(i.e. 24h vs 48h)
Discuss Sheffield - Moore et al (2004)??? When looking at muscle protein breakdown following endurance exercise.
Delta change in Ra from rest was sig higher 10 min post ex for both young and old men.
Delta change in fmo was sig higher 10 min post ex for just older men.
What did Louis et al (2007) show??
Following resistance exercise, mURF1 was significantly higher after 1h, 2h and 4h of exercise.
Atrogin and Foxo3A were significantly lower at 8h and 12h
What did Borgenvik et al (2012)??
Showed a placebo was significantly higher than BCAA for MAFbx in both resting and exercising legs in post ex compared to pre ex.
The placebo was also sig higher than BCAA for exercising leg when looking at muRF-1.
Discuss Borhseim et al (2004)??
Found Phe net balance to be significantly higher at 3rd hour post drink for CHO group compared to placebo. No differences were found between CHO and placebo on phe Ra into blood.
Discuss Greenhaff et al (2008)???
Stated that insulin action is permissive for NPB at rest.
Insulin does not reduce MPB, increase MPS and improve NPB when amino acid provision is sufficient to maximally stimulation anabolism.
Discuss Staples et al (2011)???
Built from Greenhaff (2008) showed that additional carbs did nothing for MPS and MPB.
Concluded that insulin action is permissive for NPB after exercise