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Researched and Composed by Jacob Wilson and Gabriel "Venom" Wilson
Abstract
Several studies have examined and compared the effect of exercise
intensity on substrate utilization. The purpose of this paper was to
provide insight on these findings.
Exercise Intensities Compared in terms of Fat Oxidation during the
Exercise Session
In one of the most well composed studies in modern times, Romijn et
al. (1995) investigated the effect of intensity and duration on
substrate utilization during exercise. Participants consisted of six
trained endurance athletes, while the apparatus consisted of a cycle
ergometer. Exercise was performed at 25, 65, and 85 % V02 maximal
capacity. Whole body carbohydrate as well as lipid oxidation were
measured. Carbohydrate oxidation was fractionated into fuel utilized
from plasma glucose, as well as intramuscular glycogen stores. Fat
oxidation was fractionated into exogenous fatty acids derived from
adipose depots and intramuscular glycogen stores. Whole body lipolysis
was also measured.
In review, oxidation is the process by which energy is extracted
from fuels. Fat oxidation, in laymen’s terms is often referred to as
fat burning. In this context whole body lipid oxidation, would refer to
the amount of total fat ‘burned’ during a workout. In scientific terms
it is more accurate to use the term oxidation as opposed to burned.
Whole body carbohydrate as well as lipid oxidation were measured by
indirect calorimetry. Indirect calorimetry can be defined as the
process which measures oxygen consumed and correlates it to fuel
metabolism. For example, if carbohydrates are used as fuel, then one
liter of oxygen consumed is assumed to have metabolized 5.047
kilocalories of carbohydrate. However, more complex procedures allow
the experimenter to extrapolate the percentage of fuel used from
carbohydrates as well as fats from this method ( for more on indirect
calorimetry, see
Wilson
and Venom, 2004 -
Energetic Transference
Occurring in the Biosphere Part I ). Endogenous or
peripheral carbohydrate and lipid oxidation were found by measuring the
rate of glucose and fatty acid disappearance rate to indicate the amount
taken up by the musculature and oxidized. To find intramuscular
glycogen and triglyceride utilization, peripheral glucose and lipid
oxidation were subtracted from whole body carbohydrate and glucose
oxidation.
Lipolysis is defined as the catabolism of a
triglyceride into three fatty acids and one glycerol molecule. In order
to be metabolized, glycerol must be first phosphorylated by glycerol
kinase. However, only the liver has a significant amount of this
enzyme, meaning it is not utilized by muscle tissue in significant
amounts, and is therefore released into the blood stream. Therefore,
glycerol released by lipolysis from muscle and adipose tissue provide an
accurate reflection of whole body lipolysis.
Comparison of various exercise intensities on
plasma glucose concentrations after 30 minutes of cycling found that as
intensity increased, plasma glucose concentration increased.
Specifically, the mean values were 77, 98, and 147 milligrams per
deciliter of plasma glucose concentrations for 25, 65, and 85 % V02 max
intensities. This facilitated a higher reliance on glucose, as
carbohydrate utilization increased as intensity increased. In the 25 %
V02 max condition, carbohydrate oxidation provided approximately 7.5 %
of the fuel used. Further, muscle glycogen stores did not contribute
significantly to this number, suggesting almost complete reliance on
peripheral glucose. In the 65 % condition, carbohydrate utilization
provided approximately 50 % of the fuel utilized, with 80 % of this
coming from intramuscular glycogen stores. During the 85 % V02 max
condition, 75 % of the energy was derived from carbohydrate utilization,
with 80 % coming from muscle glycogen stores.
Comparison of glycerol utilization among conditions found that there was
no significant difference between intensities on lipolysis from adipose
tissue. However, intramuscular lipolysis at 65 and 85 % V02 max
conditions had higher glycerol levels than the 25 % V02 max condition.
This may be a consequence of catecholamine concentration.
Catecholeamine plasma concentration increased with exercise intensity.
This suggests that adipose tissue can have a high rate of lipolysis at
low catecholamine stimulatory levels. It further suggests that the
threshold for intramuscular triglyceride lipolysis is higher than the
adipose tissue threshold. However, even though whole body lipolysis was
greater during higher intensities, fatty acid appearance in the blood
plasma was highest in the 25 % and 65 % V02 max conditions and lowest in
the 85 % V02 max condition. This is a consequence of the chemical
properties of triglycerides. As stated, they are comprised of a
glycerol molecule and three fatty acids. The glycerol is water soluble,
however, the fatty acids are water insoluble and must be transported by
albumen ( a transport protein ) in the blood. High catecholamine levels
appear to cause vasoconstriction to adipose and inhibit blood flow to
the region, and therefore do not supply an adequate amount of albumen
for transport. This does not impede the water soluble glycerol from
increasing in its rate of appearance, as it is not dependent on any
transport protein. This postulation was further supported upon
cessation of exercise. Romijn et al. (1995) found that as high
intensity exercise ended, a transient rise in free fatty acids was
found, with a concomitant decrease in plasma glycerol. This suggests
that triglycerides were not being catabolized, but rather the fatty
acids previously cleaved from the glycerol molecule during high
intensity exercise were now able to be transported out of the adipose,
after sympathetic activity lowered, and blood flow increased to the
region.
The proportion of fat oxidation, showed an
inverse relationship with exercise intensity. Over 85 % of the fuel
during 25 % V02 max was provided by fatty acids from adipose, while 7.5
% was provided by intramuscular TGs. In the 65 % condition, 50 % of the
fuel was derived from lipid oxidation, in equal measure from adipose and
intramuscular stores. The lowest percentage was found in the 85 %
condition, with only 25 % of the fuel coming from lipid oxidation from
equal measure of adipose and intramuscular TGs. However, total calories
utilized increased as exercise intensity increased. Of those calories,
total fat oxidation was highest in the 65 % V02 max condition, while
there was no significant difference between the 25 and 85 % V02 max
conditions. Of those fats utilized, the greatest amount of lipid
oxidation derived from adipose tissue came from the 25 % V02 max
condition, followed by the 65 % V02 max condition. Adipose derived fat
oxidation was lowest in the 85 % V02 max condition.
Romijn et al. (1995) was not able to quantify
the effect of duration on the 85 % V02 max condition, due to the
inability to maintain that intensity for longer than 30 minutes. The
effect of duration from 30 minutes to two hours found no change in fuel
availability in the plasma or percentage of fuels utilized. However,
the effect of duration on the 65 % V02 max condition found that plasma
glucose and
FFA
availability increased from 30 – 120 minutes, suggesting that the
musculature began to rely to a greater extent on peripheral fuels.
There are several possible mechanisms for this. For example, it could
be postulated that a decrease in intramuscular TGs stimulated the
increase in plasma ffas. Romijn et al. (1995) postulates the opposite.
This is because currently there is no known mechanism by which
intramuscular TGs can regulate lipolysis from adipose tissue.
Therefore, they suggest that an increase in plasma FFA concentration,
and subsequent increase in muscular
FFA
uptake and concentration, decreased the utilization of intramuscular TGs.
This is supported by the rate of fatty acid appearance when comparing
the 25 to 65 % V02 max conditions. In the 25 % condition, fatty acid
appearance in blood plasma increased immediately. However, it slightly
decreased at first in the 65 % V02 max condition, followed by a
progressive increase.
From the above findings it should be noted that
total fat oxidation is greatest at moderate intensity, while total
glycogen depletion is greatest at high intensity exercise. Fat utilized
from adipose tissue was greatest in the low intensity condition, while
glycogen depletion was lowest at this intensity. This suggests, that
based on lipid oxidation, that 65 % V02 max is optimal, followed by low
intensity exercise. Further, the lower the intensity, the greater the
sparing effect on glycogen stores will be.
Romijn’s et al. (1993) findings on maximal fat oxidation occurring
when training within 60% of VO2 max has been supported by numerous
studies. Achten et al. (2002) had eighteen moderately trained cyclists
perform a graded exercise test to exhaustion, with 5-minute stages and
35-weight increments. To elaborate, a graded exercise test is when an
athlete progressively increases intensity after each time steady state
is reached, usually until complete exhaustion. It was found that maximum
fat oxidation occurred at 64% VO2 max, +/- 4%. Conversely, the
contribution of fat oxidation to energy expenditure became negligible
above 89%. In another study fifty-five male subjects performed another
graded exercise test on a cycle ergometer (Achten and Jeukendrup, 2003).
Results demonstrated that maximum fat oxidation was reached at 63% VO2
max. Thus, evidence clearly suggests that training within 60% of your
VO2 max is optimal for fat oxidation.
The
Effect of Exercise Intensity on EPOC
It is well established that exercise increases oxygen consumption
for several hours after its completion (Gaesser and Brooks, 1984). As
discussed, oxygen consumption is used to assess caloric expenditure.
Therefore elevated levels of 02 consumption reflect a higher resting
metabolic rate. Explanations for such a phenomenon are connected to a
number of historical events. It all began with Berzelius, who in 1808
found that lactate concentration was increased in ‘ the muscles of
hunted stags( Gladden, 2004)’ who relied on anaerobic pathways to
attempt to escape their predators. This was followed by Myeroff’s
(1920) discovery that glycogen served as a precursor for lactate
(Gladden, 2004). Building on this work, Hill proposed the 02 debt
theory, which suggested that 1/5 of the increase in 02 consumption was
used in the oxidation of lactate. This in turn provided the energy to
convert lactate build up during exercise back to glycogen, thus repaying
the ‘debt’ incurred through anaerobic processes. Scientists further
noted that the 02 debt produced a curve that was characterized by a
rapid phase of 02 dissipation, followed by a slow phase of decline.
Margaria et al. (1933) called the fast phase alactacid, followed by the
slower lactacid phase. The alactacid phase was postulated to account
for replenishment of non lactic acid components of anaerobic energy
utilization, such as the phosphorylation of free creatine to form
creatine phosphate. The lactacid phase was said to replenish glycogen
stores from lactate. However, Gaesser and Brooks (1984) suggested that
these explanations were to simplistic and that evidence pointed to the
majority of lactate being oxidized following exercise, with the
remainder serving as a carbon skeleton for a number of processes of
which glycogen replenishment is just one. Further, it was stated that
the oxygen utilization could be linked to a number of phenomenon,
including the residual effects of hormones, and increased temperature.
In this historical review, Gaesser and Brooks (1984) introduced the new
terms - excess post exercise oxygen consumption (EPOC) and recovery 02
to eliminate the ‘ implication of causality in describing the elevation
in metabolic rate above resting levels after exercise.’
Today another historical battle exists. Across countries exercise
participants purport the superiority of high intensity interval training
(HIIT) which is short over low to moderate intensity long duration
training. One of the purposes of this article is to analyze the
evidence for this claim and allow the reader to conclude from there.
Shawn Phillips, one of the leading spokesman for HIIT stated that
‘You
knew deep down, anyhow, that busting your butt burned off more fat than
an exercise that allowed you to read at the same time, didn't you? Well,
research shows our instincts were right…
HIIT
speeds up your metabolism and keeps it revved up for some time after
your workout. The bottom line is HIIT training burns a greater number of
total calories than low-intensity training, and more calories burned
equals more fat lost. What I'm suggesting is you forget about the
"calories burned" readout on the stairstepper or Lifecycle; if you
practice HIIT training, the majority of calories burned will come after
your workout!’
The
above statement paints an appealing picture. In reality however, the
scientific evidence suggests that it is unequivocally false (Laforgia et
al., 1997, Gore and Withers, 1990,
Freedman-Akabas,
1985). First, HIIT training is normally purported to take less time
than lower intensity sessions. However, to control variables Laforgia
et al. (1997) examined the effect of intensity on EPOC, while matching
total work performed in each session. Participants consisted of eight
male middle distance runners, who performed 30 minutes of 70 % V02 max
treadmill running in condition one, and interval training in condition
two. Interval training consisted of 20, one minute sprints at 105 % of
V02 max. The session lasted 60 minutes, as sprints were interspersed
with 2 minute intervals in which participants performed active
recovery. It was found that the 70 % V02 max condition metabolized 31
extra calories over the entire nine hours following exercise, while the
high intensity condition metabolized 64 extra calories as extrapolated
by EPOC. This equates to a negligible 33 extra calories for the high
intensity condition. Laforgia et al. (1997) suggests that a comparison
of the excess calories above moderate intensity exercise ‘for the
interval treatment is of little physiological significance to
the energy balance of athletes because this amount of energy
is equivalent to the kilojoules in only 75 ml of orange juice
(1/3rd cup).’ They further conclude that ‘the major
contribution of both treatments to weight loss was via the energy
expended during the actual exercise. The excess post exercise energy
expenditure is therefore of negligible physiological significance as far
as weight loss is concerned.’
In another study, Gore et al. (1990) examined the effect of both
intensity and duration on EPOC. Participants consisted of nine males
with an average of 21 years of age. Participants exercised at 30 %, 50
%, and 70 % V02 max, each at 20, 50, and 80 minute durations. The
effect of duration on exercise found no significant difference in the 30
% V02 max condition, whose 8 hour EPOC was a little over 1 liter of 02,
amounting to approximately 5-6 extra calories metabolized. The effect
of duration on the 50 % V02 max condition found that EPOC went from
approximately 3 liters at 20 minutes, to 5 liters at 50 minutes, and
finally to 6 liters at 80 minutes of duration. The effect of duration
on the 70% V02 max condition found that EPOC went from 6, to 10, and
finally 14.6 liters of 02 consumed for 20, 50, and 80 minute durations.
As a reference the 14.6 liters of 02 consumed in excess in the 70 % V02
max, 80 minute duration condition was approximately 70 extra calories of
energy expended or approximately 40 extra calories than the 50 minute
condition at 50 minutes duration. While the data from this study
clearly shows a positive relationship between intensity and duration on
EPOC, the amount of calories metabolized in excess is concluded by the
authors to be ‘ of little physiological significance for weight loss…’
Further, the average amount of calories metabolized during EPOC was
approximately 4 % of the total energy cost of exercise, which addresses
the statement that
,
‘the majority of calories burned will come after your workout(
Phillips)!
Further, the 70 % V02 max condition is comparable to the 65 % condition
discussed in the
Romijn et
al. (1995) study which metabolized the highest amount of fat during
training. This is significant because the EPOC in the supramaximal high
intensity condition in the Laforgia et al. (1997) study, was nearly
equivalent to the 70 % V02 max, long duration session. This suggests
two outcomes. First, if exercise is performed at 65 % V02 max for a
longer duration such as 60 minutes, then the EPOC generated may possibly
approximate HIIT training intensities, secondly during the training
session overall calories expended will be greater, with a higher
proportion of those calories coming from lipids, as opposed to the
overwhelming majority of glycogen utilization found in the supramaximal
protocol.
The next inherent flaw made in the hi intensity vs. low to moderate
intensity argument is that it fails to take into account the fact that
bodybuilders are primarily high intensity athletes. As such they may
already receive the benefit of optimized EPOC.
Melby et al. (1993) tested the effect of resistance exercise on
metabolic rate during the 2 hours following exercise and on resting
metabolic rate (RMR) the following day, measured 15 hours after
exercise. Seven males with previous experience in resistance training
performed 60 sets of both upper and lower body exercises, over a
90-minute time span. 2 hours after exercise, the average total EPOC was
7 Liters of O2, which adds up to about 35 extra calories oxidized in
comparison to the control group. The total EPOC after 15 hours of
exercise accounted for approximately 180 extra calories metabolized. In
another experiment (Jamurtas et al., 2004) ten male athletes lifted
weights for 60 min at 70-75% of 1-RM. It was found that the weight
lifting group utilized had a 150 calorie increase in resting energy
expenditure as extrapolated from EPOC.
Optimizing Hi and Low Intensity Exercise
Again, the inherent flaw in HIIT arguments when appealing to
bodybuilders is to negate the fact that they are exposed almost daily to
high intensity exercise. The key is to understand the purpose of
various exercise regimens and incorporate them properly. Bodybuilders
enter the weight room with the goal of maximizing hypertrophy. In order
to maximize hypertrophy, they attempt to continually perform at
extremely intense protocols within an optimal hypertrophy repetition
range (Fry, 2004). However, the ability to maintain intensity during a
cutting phase is highly dependent on intramuscular glycogen stores.
Wilson (2003) in his article on ‘ Pre Contest An In Depth Analysis’
explains:
Glycogen's importance in athletic performance
is well documented. For example, in the Canadian Journal of Physiology,
biopsies (in the biceps) were examined in 8 bodybuilders across a
typical arm-curl training session. After only one set researchers
found that muscle glycogen stores in the Biceps had decreased by a
whopping 12 percent (MacDougall et al. 1999)! Haff et al. (2000) noted
that after three sets of leg extensions, that the vastus lateralis
(outer quad sweep) was depleted of 17 percent of its glycogen stores.
Tesch et al. (1998) found a 40 percent decrease in glycogen stores after
5 sets of 10 repetitions on concentric knee extensions (extensions minus
the lowering phase) at 60 percent of the participants 1 repetition
maximum.
In another study Robergs et al. (1991) investigated skeletal muscle
glycogen metabolism in eight male participants during and after six sets
of 70 % one repetition maximum. It was found that leg extensions
performed at 70 percent 1RM, decreased muscle glycogen stores by 39
percent. The question now is, what happens to performance when fuel is
low. Jacobs, Kaiser, and Tesch (1981) investigated the effect of
depleting varying muscle fibers on strength levels. One group depleted
both fast and slow twitch muscle fibers through long duration cycling
and sprint cycling on the bicycle ergometer. In a second condition,
Slow twitch fibers were depleted through extremely long duration
marathon style training. It was found that glycogen exhaustion from the
group that depleted both fiber types in the vastus lateralis was
associated with impaired maximal muscular strength produced during a
single dynamic contraction, as well as with reduced muscle fatigue
patterns. When glycogen depletion was induced in slow twitch muscle
fibers mainly, maximum strength was not hindered. Suggesting that the
loss in strength in the two fiber group was primarily a function of
glycogen depletion in fast twitch muscle fibers.
In
another study Balsom et al. (1999) examined the effect of glycogen
depletion during a low carbohydrate diet compared to a high carbohydrate
diet on hi intensity all out 6 second sprints on a cycle ergometer, with
30 second intervals between sprints. Conditions were further divided
into a 10 minute or 30 minute total session of sprints. Glycogen levels
were significantly lower in the low CHO diet than the hi CHO diet. In
both the short and long hi intensity training sessions, significantly
less work was performed following LOW-CHO compared with HIGH-CHO
protocol. The ability to maintain pre determined intensities was 265 %
higher in the high cho condition than the low cho condition. Further,
at the point of fatigue the low CHO group had significantly lower
glycogen stores than the hi CHO condition. For more information on
glycogen and its effect on exercise see Wilson and Venom (2004)
Energetic Transference
Occurring in the Biosphere Part II.
Results consistently show that the key to maintaining performance is
intensity.
The word
intensity, however, is ambiguous. In this case, it refers to percent of
a one repetition maximum performance. What this means is that the
participant must maintain their original intensity, in order to preserve
their gains. Therefore if an individual usually lifts at 6 repetitions
for squats, they should maintain that lift during their cut. As an
illustration, if on most weeks the individual squats 400 pounds for a
rep scheme of 10, 8, 6, and they decide to drop this down to 300 during
their cut, they would lose a significant amount of adaptations, and very
rapidly.
For
example, to test changes in V02 max—which is the maximal amount of
oxygen an individual can take in, transport, and utilize to produce
energy at the cellular level—athletes were put on a 10 week intense
interval training program, followed by a 15 week reduction in training
frequency (Hicksonm et al., 1981). Training was reduced from 6 days per
week, to 2-4, while intensity and duration were maintained; training
induced improvements in VO2 max were maintained. Further, when duration
was decreased from 40 minutes, to 26, and finally13, VO2 max was also
maintained. Now here is the interesting part; when intensity was reduced
by 1/3 to 2/3rds, improvements were not maintained. Additionally, once
flexibility has been attained, it can be maintained by just one session
per week of training at the same intensity (Walin et al., 1985).
Trappe, Costill, and Thomas (2000) performed an excellent experiment to
examine the changes in whole muscle function and single cell contractile
properties of Type I and II muscle fibers from the deltoid muscle of
highly trained swimmers before and after a 21-day reduction in training
volume, while maintaining there intensity. Results demonstrated whole
muscle power increased 17% and 13% on the swim bench and swim power
tests; Type IIa fibers were 11% larger; Peak force increased
significantly in fast twitch fibers; and shortening velocity was 32% and
67% faster in the Type I and IIa fibers, respectively.
This phenomenon of restitution gains is know as ”tapering”, and
will be covered in-depth in future issues of JHR. Suffice if to say,
results suggest that intensity is the number one variable for
maintaining performance gains, and excessive depletion of glycogen
stores will inevitably hinder this aspect of training.
As
stated, the weight room provides a tool to hypertrophy as well as change
body composition. However, cardiovascular training, in terms of
bodybuilding can supplement this tool by providing a caloric deficit,
conducive to maintaining current musculature. Evidence suggests that a
caloric deficit induced through exercise is optimal for fat loss, then
compared to the same deficit induced through diet.
Tsai
et al.
investigated the effect of creating a 25 % caloric deficit through
either diet or exercise in 13 participants. Participants were
randomized into exercise or diet induced deficit conditions. This was a
two phase study. Participants in condition 1, during phase 1 would
switch to condition 2 in phase 2. Phases were separated by 5 days of
energy repletion. Comparison of exercise and diet induced energy
deficit conditions found that the dieting condition lost more weight,
than the exercise condition. However, the exercise condition lost more
body fat. For the bodybuilder, this provides the benefit of maintaining
size while losing more body fat.
This combined with lower glycogen depletion of fast twitch fibers
suggests that low to moderate intensity cardiovascular training can
provide a tremendous tool to the bodybuilder.
Split Training
The
question has arisen on whether splitting cardio into two sessions,
rather than one in a given day, would increase gains. Almuzaini et al.
(1998) investigated how splitting a 30-minute exercise bout on a cycle
ergometer into two equal sessions effected excess post exercise oxygen
consumption. Ten male volunteers participated in two trials.
One trial
consisted of 30 minutes of exercise at 70% VO2 max. The second trial was
divided into two 15-min sessions, separated by 6 hours. A 20 minute
measurement of EPOC was performed following each workout. Results showed
that there was a significant overall increase from the two split
training sessions (7.4 L of 02 consumed) compared to the single 30
minute session (5 L of O2 consumed). In a related study, by Kaminsky et
al. (1990), EPOC was analyzed in six women following either a continuous
50 minute run, or 2-25 minute runs, separated by breaks in-between
sessions, at 70% VO2 max during each trial. Results again demonstrated
that EPOC following the split training session was significantly greater
than one long duration session. Although, EPOC plays a small role in
energy expenditure, split training will increase EPOC more than one
continuous cardio session. Additionally, this could have psychological
benefits, as doing a long cardio session, for instance, can be extremely
tedious. Thus, separating cardio into two sessions may be of interest to
the reader for this reason alone.
This further lends credence to
Wilson’s
(2003) dissertation on split training (read
Hippocrates - Was He
Hardcore?). Within, he clearly demonstrated that split
training improves focus, and performance during each training session.
Further, splitting workouts into two sessions would raise anabolic
hormones two fold, instead of only once per day.
However, there is another vital issue to consider here. During long
duration cardio, your ability to mobilize peripheral fats for fuels
progressively increases. Thus, an hour of moderate intensity cardio, for
fat burning effects, may be more beneficial, than separating it into two
thirty-minute sessions. However, if an individual is to perform a short,
20 minute HIIT workout, in which carbohydrates are the dominant fuel
used throughout, there should only be benefits from separating this into
two 10-minute sessions.
Practical Applications
Evidence suggests that as exercise intensity decreases, there is an
increased reliance on the peripheral adipose depot, with a concomitant
sparing of carbohydrates, particularly intramuscular glucose polymers.
It appears that fat oxidation becomes optimal within the range of 60%
VO2 max. However, training below this range (>50% VO2 max) may be
beneficial during states of overtraining, and or severe caloric
restriction.
An
analysis of scientific literature demonstrates that the maintenance of
adaptations are intensity specific. The reader is, therefore, cautioned
to avoid over reliance of high intensity, glycogen depleting protocols.
High
intensity training may prove beneficial if used properly. For example,
its potent stimulation of whole body lipolysis during exercise leads to
a rapid influx of plasma free fatty acids after intensity is lowered. In
this context, it is postulated that performing a notably short, high
intensity session, followed by a long duration, low to moderate
intensity workout, may optimize lipid oxidation.
Amidst
hypertrophic growth cycles, in which there is a caloric surplus, short,
high intensity workouts may elicit a supplementary anabolic stimulus.
This is attributed to preferential recruitment of type II fibers, which
have the greatest capacity for growth, as well as an increase in
anabolic hormones.
Conclusion
John 8:32
And ye
shall know the truth, and the truth shall make you free.
Seek the truth, spurn unscientific dogma, and your gains will grow
exponentially.
Happy New Year!
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