Questo per dare un minimo di credibilità alla mie ipotesi...
(l'ho postato anche su bodyweb, dove ne staimo discutendo con duch)




Resting energy expenditure in short-term starvation is increased as
a result of an increase in serum norepinephrine1,2
Christian Zauner, Bruno Schneeweiss, Alexander Kranz, Christian Madl, Klaus Ratheiser, Ludwig Kramer, Erich Roth,
Barbara Schneider, and Kurt Lenz

ABSTRACT
Background: The effects of food restriction on energy metabolism
have been under investigation for more than a century. Data
obtained are conflicting and research has failed to provide conclusive
results.
Objective: The objective of this study was to test the hypothesis
that in lean subjects under normal living conditions, shortterm
starvation leads to an increase in serum concentrations of
catecholamines and thus to an increase in resting energy
expenditure.
Design: Resting energy expenditure, measured by indirect
calorimetry, and hormone and substrate concentrations were
measured in 11 healthy, lean subjects on days 1, 2, 3, and 4 of an
84-h starvation period.
Results: Resting energy expenditure increased significantly
from 3.97 ± 0.9 kJ/min on day 1 to 4.53 ± 0.9 kJ/min on day 3
(P < 0.05). The increase in resting energy expenditure was
associated with an increase in the norepinephrine concentration
from 1716. ± 574 pmol/L on day 1 to 3728 ± 1636 pmol/L
on day 4 (P < 0.05). Serum glucose decreased from 4.9 ± 0.5
to 3.5 ± 0.5 mmol/L (P < 0.05), whereas insulin did not change
significantly.
Conclusions: Resting energy expenditure increases in early starvation,
accompanied by an increase in plasma norepinephrine.
This increase in norepinephrine seems to be due to a decline in
serum glucose and may be the initial signal for metabolic changes
in early starvation. Am J Clin Nutr 2000;71:1511–5.


4 gg di digiuno (solo h20) aumentono il RMR di circa 360 calorie in + al giorno
Naturalmente come Benedict notò nel 1915 il digiuno prolungato porta ad calo del BMR di circa il 20 o 30% (ciò è da ricollegarsi anche alla perdita di peso)
Questo sfata il mito che il digiuno nel breve termine porti ad un calo del metabolicmo.

Adesso occupiamoci della perdita di massa grassa che tutto voi BB (io pratico arrampicata sportiva e come Duch nn me ne frega nulla dello stimolo ipertrofico)

Elevation of Plasma Epinephrine Concentrations Inhibits Proteolysis
and Leucine Oxidation in Man via @i-Adrenergic Mechanisms
M. E. Kraenzlin, U. Keller, A. Keller, A. Thelin,* M. J. Arnaud, and W. Stauffacher
Department ofMedicine, University Hospital, CH-4031 Basel, Switzerland; and *Nestec SA, CH-1800 Vevey, Switzerland
Abstract
The role of elevated plasma epinephrine concentrations in the
regulation of plasma leucine kinetics and the contribution of
,8-receptors were assessed in man. Epinephrine (50 ng/kg per
min) was infused either alone or combined with propranolol
(f,-blockade) into groups of six subjects fasted overnight; leucine
flux, oxidation, and net plasma leucine forearm balance
were determined during 180 min. Constant plasma insulin and
glucagon concentrations were maintained in all studies by infusing
somatostatin combined with insulin and glucagon replacements.
Plasma leucine concentrations decreased from
baseline during epinephrine infusion by 27±5 gmol/liter (P
< 0.02) due to a 22±6% decrease in leucine flux (P < 0.05 vs.
controls receiving saline) and to an increase in the metabolic
clearance rate of leucine (P < 0.02). Leucine oxidation decreased
by 36±8% (P < 0.01 vs. controls). fl-Blockade abolished
the effect of epinephrine on leucine flux and oxidation.
Net forearm release of leucine increased during epinephrine (P
< 0.01), suggesting increased muscle proteolysis; the fall of
total body leucine flux was therefore due to diminished proteolysis
in nonmuscle tissues, such as splanchnic organs. Nonoxidative
leucine disappearance as a parameter of protein synthesis
was not significantly influenced by epinephrine. Plasma
glucose and FFA concentrations increased via f,-adrenergic
mechanisms (P < 0.001). The results suggest that elevation of
plasma epinephrine concentrations similar to those observed in
severe stress results in redistribution of body proteins and
exerts a whole body protein-sparing effect; this may counteract
catabolic effects of other hormones during severe stress.

Come si nota l'aumento di catecolamine tende a preservare la massa magra, questo adattamento naturalemente dura poco (ricollegandoci al primo studio, circa 4 o 5 gg). Aumentando il digiuno e quindi i fattori stressori avremo dei livelli sovrafisiologici di cortisolo, vero ormone proteolitico (a livelli sovrafisiologici)