Recommended Readings:
The Window of Opportunity
Sodium - A comprehensive Analysis
Active Recovery - A Threefold Breakdown
Dextrose, Maltodextrin, and Sodium an In Depth Analysis
Sea Water
Water, water everywhere
Nor any Drop to Drink
This famous line is from
the great poet Samuel Taylor Coleridge. He wrote it during his epic poem, “The
Rime of the Ancient Mariner,” which depicts the life of a sailor. So what is
Samuel’s point? Allow me to elaborate.
As you well know, sailors
are surrounded by water all day. However, they can not depend on the ocean for
sources of fluid. Hence, the line, “Water, water everywhere Nor any Drop
to Drink.” The reason being drinking salt water would severely dehydrate them,
resulting in certain death. This danger results from the concentration of
solutes dissolved within the ocean. The osmolarity of sea water ranges from
2000-2,400 mOsm, primarily contributed by sodium chloride. This is 8 times the
osmolarity of your plasma--300 mOsm. The most concentrated urine our kidneys can
produce ranks at 1400 mOsm, far below the level of ocean water.
Let’s say during a
hardcore training session you excreted approximately 1 liter of water from sweat
alone. Afterwards, you replace this water with a liter of sea water. This would
initially return your plasma volume back to normal levels. However, because the
sodium concentration of ocean water is so high, your plasma osmolarity would
skyrocket. This would stimulate the release of the Antidiuretic Hormone (ADH,
explained in the aforementioned sodium article), causing your body to secrete a
minimal volume of concentrated urine, assisting in water conservation, lowering
osmolarity. Ideally, your body would secrete all the solute, with only small
amounts of water. But this is not possible, because as mentioned earlier, the
highest urine concentration is 1400 mOsm. To excrete 2400 milliosmoles of salt
water, your kidneys would have to release at least 1.7 liters of water (the
amount of water which accompanies the solute is known as the obligatory water
loss). The amount of fluid lost is almost twice as much as you originally
ingested!
Therefore, drinking
seawater would cause more water to be lost in your urine than orally consumed,
resulting in a net loss of bodily fluids. As such, the athlete who drank salt
water post-workout would actually promote dehydration, which brings us to our
topic of discussion.
Thermoregulation- Introduced
Thermoregulation refers to
the control of body temperature within a narrow range. This is done by adding or
subtracting body heat. Core temperature rises if heat gain exceeds heat loss.
This readily occurs during intense exercise in humid environments. In contrast,
in the cold, when heat loss exceeds heat production, core temperature falls. A
drop in core body temperature of 10 degrees and an increase of 5 is tolerable;
beyond this, however, can be fatal. Multitudes of heat related deaths in the
past 20 years certainly attest to this [39]. Since the metabolism of an elite
athlete often rises 20 to 25 times above resting level, your body would, in
theory, increase temperature by 1 degree every 6 minutes. However,
thermoregulatory adjustments help prevent this from occurring [30, 40].
Several mechanisms are
involved in thermoregulation. Indeed, this is a complex subject, and several
journals must be dedicated to adequately serve it justice. This issue will focus
primarily on hydration.
To begin, we discuss the
sweat mechanism.
Sweat
There are more than 2.5
million sudoriferous (sweat) glands distributed over the surface of the human
body. These consist of apocrine and eccrine glands. The former plays little role
in thermoregulation, thus, we will focus on eccrine glands exclusively.
Eccrine
glands
These sweat glands are
abundantly found on the palms, soles, and the forehead. They are small, tubular,
coiled glands of the merocrine variety (refers to a common mode of secreting
substances to the exterior portion of the body). The secretory portion is coiled
within the dermis (connective tissue underlying the epithelium of the skin),
while its duct extends up to open a funnel-type pore at the skin’s surface.
This secretion is what we
normally refer to as sweat. Sweat is derived from blood plasma filtration. Its
composition is 99% water, with the rest coming primarily from sodium, along with
antibodies, lactic acid, vitamin C, and metabolic wastes. The exact composition
can vary according to genetics and diet. It is an acidic substance with a pH
between 4 and 6 (remember, the lower the pH, the more acidic the solution).
Sweat is monitored by the
sympathetic division of the autonomic nervous system. We have little control
over this system. One of its primary purposes is thermoregulation, in the
prevention of over-heating.
Heat-induced sweat starts on the forehead and spirals downward over the body.
Emotional conditions, also known as the, “cold sweat,” are brought on by
nervousness, fright (i.e. seeing a gym moron approaching you to give advice!),
embarrassment, etc. Secretion begins on the palms, soles, and armpits, and then
spreads to other parts of the body.
Evaporation
In relation to training,
when body temperature rises, sweat is released, acting as a refrigeration
mechanism to cool the body. Sweat is not actually what cools your body, but
rather, evaporation. Each liter of water that vaporizes by sweat exerts 580 kcal
from the body and transfers it to the environment. The cooled skin in turn cools
the blood diverted from interior tissues to the surface. Blood flow is vital to
the sweat mechanism. This will be discussed further on.
Humidity heavily affects
the efficiency of the sweat mechanism. Air becomes saturated with water vapor at
100% relative humidity. This blocks any evaporation of fluid. In such
conditions, sweat would eventually roll off your body without providing any
cooling. On a dry day, the air can hold considerable moisture, and fluid
evaporates quickly from the skin. High temperatures are handled relatively well
by the body. It is more comfortable to train in dry desert climates than cooler,
but more humid environments.
Note:
Condensation is an energy releasing process. In a humid environment, more water
is condensing on your skin, and thus releasing energy to the skin in the form of
heat. Such a concept is easy to test. When you turn off the shower, it is still
warm as water condenses on the skin. However, when you walk out of the shower
you are immediately hit with the cold. This is due to the fact that more water
is evaporating (an energy-absorbing process) than is condensing. Next time you
take a shower, try dying off while in there; you will stay warmer. These
concepts are due to the amazing chemistry of water!
For more on sweat, I turn
to
Sodium - A comprehensive Analysis.
Here is a quote:
Sweat loss
“As mentioned previously, sodium
is water soluble. This relates to a large amount of sodium loss through sweat
during intense training sessions. Sweat is produced by specialized sweat glands
beneath the skin. Evaporation of sweat’s water components results in a
refrigeration mechanism to cool the body down.
Typically, a well-assimilated
athlete will loose .5L - 3L of sweat during each hour of exercise. On average,
an athlete looses 1-1.5 liters per hour. Higher intensity results in increased
sweat loss. Humidity, heat, and other weather-related factors will result in
increased sweat secretion as well. Every liter of sweat contains a whopping .6
g of sodium. This is a vital factor in optimal post-workout nutrition.
It is also important to note that
increasing heat and sweat loss before and during training sessions is extremely
beneficial to the athlete. For more on this, refer to:
Mobility Training and the Application of Proper Warm-Up for Bodybuilders.”
As you see, sweat promotes
the loss of bodily fluids. Next we analyze how to counter these effects and work
to promote thermoregulation through the most abundant component of the
body--water.
Hydration
Hydration is the
maintenance of plasma volume in the body. This is done by consuming adequate
supplies of water throughout the day.
Hydration is the most
effective defense of heat stress. Furthermore, a well-hydrated athlete will
predominantly perform at a higher proficiency than a dehydrated one.
Proper hydration during
exercise is of the utmost importance. Fluid ingestion must be strictly monitored
in order to achieve maximum results. Most athletes, however, do not adequately
replace water loss. They instead rely on the thirst mechanism. While this is
helpful, it does not precisely monitor water needs. When unlimited amounts of
water are supplied, and athletes do not consume enough water voluntarily,
dehydration occurs. This is known as voluntary dehydration. For example, if you
were to entirely rely on the thirst mechanism for rehydration after being
severely dehydrated, it would take several days to regain fluid balance [35]. As
such, athletes must know the exact science behind rehydration, and follow it to
a T [34]. Subsequently, we will analyze this, and the anabolism behind
hydration.
Water
Water makes up 40-70% of
body mass, and 75% of muscular weight. It is a vital nutrient. Without water,
death would occur within a few days. Waste products leave the body through water
in the urine and feces. Water lubricates the joints, and organs such as the
heart, and intestines. It also provides structure for bodily tissues. Moreover,
water has great thermoregulatory qualities because it absorbs high amounts of
heat with minuscule changes in temperature, and has a high heat of vaporization.
These traits are imperative for internal heat generated amidst exercise, and
external heat stress. Dehydration will decrease athletic performance [2, 3, 10,
12, 38].
Staying hydrated during
exercise greatly benefits the athlete. These anabolic traits will be discussed
as follows:
-
Cardiac Output
-
Lactic clearance
-
Blood flow and Sweat
Cardiac
Output
Hydration has been shown
to be an effective means of increasing cardiac output. The reason is threefold.
First, the more blood plasma you have, the more blood your heart can pump
throughout your body. Secondly, your heart is a very elastic organ, and optimal
filament overlap is not reached until it is notably stretched. Increasing plasma
volume (via water) effectively accomplishes this, inducing more forceful
contractions from the heart and with it an increase in blood flow. Moreover, if
stroke volume goes down (how much blood is pumped out of the heart), heart rate
goes up in order to maintain cardiac output. The higher the heart rate, the
quicker the heart contracts, which would decrease filament overlap due to less
filling time, causing weaker contractions and minimized blood flow. In summery,
staying hydrated provides your body with more blood to use, and maximizes
filament overlap/elasticity, effectively increasing stroke volume, and
decreasing heart rate.
In light of this subject,
an experiment was performed by Hamilton et al. to test the effects that 2 hours
of moderate to heavy exercise with and without fluid replacement had on
cardiovascular conditioning [35]. When athletes consumed enough water to replace
the water lost through sweat, stroke volume did not drift down, and actually
increased, and heart rate raised only a few beats throughout the session. This
resulted in a cardiac output remaining nearly constant in the first hour of
training, with a slight increase in the latter half. When dehydrated, heart
rate increased by 10%, and stroke volume decreased by 15%, leading to a
reduction in cardiac output.
To clarify the importance
of this, here is an editor’s note from President Wilson in,
Active Recovery - A Threefold Breakdown:
“As Venom has so eloquently
displayed, active recovery exerts many of its effects by enhancing oxygen
delivery to the musculature. One of the most vital keys in your understanding of
this concept is once again centered around what Seyle in the 1950's labeled as
the "counter shock" phase of a stress reaction. To review, any activity which
requires above resting levels of work knocks the body out of balance. It
responds with a counter, by utilizing such mechanisms as increased epinephrine
levels, or dilating certain blood vessels. You must realize that this study (of
homeostatic reaction) is an intricate one. That is, differing activities
stimulate differing reactions in the body, and therefore varying "counter
shocks." Dynamic resistance training (lifting weights) for various reasons has
been shown in several studies to actually lower stroke volume.
Cardiac Output = Heart Rate x
Stroke Volume (blood ejected per beat - out of the heart)
While training intensely with
weights, heart rate actually increases markedly, as you no doubt have
noted. However, with a stagnant or lowered stroke volume, CO will only increase
moderately, a predicament which will not optimally facilitate recovery. Venom,
however, has the solution to this obvious problem. Active recovery between sets
utilizes a very aerobic (with Oxygen) protocol. During such activities, stroke
volume notably increases, and with it, Cardiac Output. Boom! You're in and 02
levels to the working musculature is instantly - optimized!”
So drinking adequate
amounts of water during intense training session has the same benefits of AR in
between sets, which has been shown to effectively enhance athletic performance
[5,6,7,11,14,16, 17, 41,42,43,44]. For more, study the aforementioned article.
Lactic Acid
For various reasons,
dehydration leads to a decrease in the lactate threshold. For example, Moquin
and Mazzeo performed an experiment on collegiate female rowers [29]. Two groups
participated in intense exercise. One was supplied adequate amounts of fluid,
while the other group was denied fluid, and trained in a sweat suit to increase
dehydration. Both groups then trained the following morning. In the dehydrated
group, there was a statistically significant (p<.05) decrease in lactate
threshold relative to the percent of VO2max, and a marked decrease in
performance both of exhaustion and power output compared to the hydrated group.
Two factors increase blood
lactate. First, reduced lactate uptake by the liver because of reduced blood
flow, and second, decreased cardiac output (CO).
Now, considering the
previous discussion on CO, this makes perfect sense. Lactate accumulation occurs
when the appearance of lactate exceeds its clearance rate. Consequently, the
number one process for lactate removal is oxidation. So when you are dehydrated,
cardiac output, and inevitably, oxygen consumption, is diminished. Hence, a
decrease in lactate threshold, and performance.
For much more on the
benefits of lactate removal, I again refer to
Active Recovery - A Threefold Breakdown.
Blood flow
and Sweat
Fluid deficits can quickly
reduce the body’s ability to dissipate heat. This is largely due to a decline in
sweat rate and blood flow. This leads to diminished cardiac function and
performance during intense exercise. Furthermore, your chance of heat illness
greatly increases in a dehydrated state [28, 36]. Dehydration of up to 5% of
body mass significantly increases heart rate and temperature, while decreasing
sweating rate, VO2 max, and exercise performance compared to a hydrated state
[31, 37]. This inevitably leads to an increase in core temperature, which has
been shown to further reduce sweat and blood flow [31].
Sudoriferous and blood are
vital to thermoregulation. We have previously discussed the benefits of sweat.
As you know, sweat depends on blood plasma for operation; dehydration decreases
blood plasma, limiting the sweat mechanism.
The circulatory system is
essential in thermal balance. When training, cardiac output increases, and blood
vessels dilate (increase in diameter) to transfer warm blood to the body
surface. This results in a reddened face on a hot day, and increased vascularity.
Enhanced blood flow can greatly assist thermoregulation. Reduced blood flow
occurs when the body is trying to maintain cardiac output because of diminished
plasma volume, caused by sweating and inadequate liquid replenishment [13]. To
clarify on the circulatory system, here is a quote from President Wilson in his
masterpiece,
The Anatomy of A Muscle.
Another cool fact - Do you know
why you get that flushed look while training? Or why your skin turns red?
Your muscles produce heat. When
they are contracting extra hard, this heat is intensified and needs to be gotten
rid of. The capillaries, aside from their above job, also dispose of heat. I
have an excellent illustration for you! What happens when you stick your hand
in hot water? Your hand turns red almost immediately right?! The same
principle applies here. When your body is producing excess heat, it is passed
to the capillaries, and they rapidly release them into the surrounding tissue,
making your skin appear reddish.
Veins are very elastic to
accommodate for blood flow and actually have muscle in the middle of their
structure. When forced to accommodate for greater blood flows veins become
stronger and can handle more blood volume. They also become more elastic.
Moreover, the muscle which is in the middle of the veins can be hypertrophied
(1) by an intensified blood flow! In other words, the muscle within will grow
and enhance the size of your veins! Anyone who emphasizes extreme blood pumps
will increase the size and strength of their veins.
Capillaries connect a muscle to
our cardiovascular system. They do contribute to the size of a muscle as well.
Increased blood demand will actually cause muscle capillarization, which means
that the density or number of capillaries will increase in your muscle cells.
Another proven method to enhance capillarization is direct cardiovascular work.
In fact the same style of cardiovascular work that I prescribe in "The Anatomy
of a Muscle Fiber" for enhanced mitochondrial density will stimulate this much
sought after adaptation!
Therefore, exercises such as
supersets, flexing between sets and anything that increases the blood pump will
increase vascularity, muscle size, and your ability to recover faster between
sets! I say it will improve recovery for obvious reasons. You will have a
greater ability to deliver precious nutrients and carry waste products outside
of your muscles!
So as you see, hydration
not only enhances thermoregulation, but blood pumps as well! Not only is a blood
pump vital for vascular hypertrophy, but also contains many anabolic nutrients.
Here is another excerpt from
Active Recovery - A Threefold Breakdown:
Leviticus 17:11
11 For the life of the flesh is
in the blood… [12]
Blood carries innumerable vital
nutrients throughout your body. A pump can assist several essential mechanisms
such as protein synthesis and cellular hydration [33]. Now, if blood carries so
many anabolic nutrients, than is there a way to channel it for the benefit of
muscular hypertrophy? Indeed there is. In this next section of the article, we
will analyze how to use blood flow to enhance recovery between workouts. First
we need to elaborate on the aspect of blood flow and its physiological effects.
Haussinger D et al. [18]
displayed evidence that cellular hydration is an important factor in controlling
cellular protein turnover, while protein synthesis and degradation are affected
in opposite directions by cell shrinking, and that an increase in cellular
hydration (swelling) acts as an anabolic agent, whereas cell shrinkage is
catabolic.
Waldegger S et al. [34] concluded
from his experiment that, “Cell swelling inhibits proteolysis (protein
breakdown), and stimulates protein synthesis, whereas cell shrinkage stimulates
proteolysis and inhibits protein synthesis”
Brad Schoenfeld [7] displayed
that a hydrated cell stimulates protein synthesis and inhibits proteolysis, in
effect, providing muscles with the raw material to lay down new contractile
proteins (myosin and actin).
Additionally, Millar ID examined
the effect of cell volume on protein synthesis [21]. The results strongly
suggest that cell volume is an important cellular signal for the control of
protein synthesis in general.
So as is clearly displayed, blood
flow is a highly anabolic agent.
In conclusion, dehydration
will halt your athletic performance, and negatively effect thermoregulation [39,
30, 40, 36, 37, 28]. Practical applications will be discussed further on.
Sodium
Exercise
causes large losses of sodium--every liter of sweat contains .6 grams of NA +.
As such, it is prudent to consume sodium post-exercise, and during exercise (if
performed long enough).
Drinks
absent or containing little amounts of sodium post-exercise dilutes blood plasma,
increase urine production (decreased fluid retention), and lower osmolarity.
This further inhibits the thirst mechanism, and delays rehydration [8, 26, 32,
21, 22]
For example,
an experiment was performed on six men following strenuous exercise in the heat
[23]. Within 30 minutes after, they ingested one of four drinks (all with 2045
ml of water) with sodium concentrations of 2, 26, 52, and 100mmol per L of
water, respectively. Those who had 2mmol of sodium excreted almost 800 ml of
water 1.5 hours later and almost 1400 ml 5.5 hours later. The best results came
with 100 mmol of sodium. Only 300 ml of water was excreted in the first 1.5
hours, and 500 in 5.5 hours--which is less than what those who had little sodium
excreted in 1.5 hours!
Furthermore,
the presence of glucose and sodium post-exercise greatly enhances intestinal
fluid absorption over plain water, due to the Glucose/Sodium co transport system
[23, 24, 25]. For much more on this and the benefits of sodium, study
Dextrose, Maltodextrin, and Sodium an In Depth Analysis
and
Sodium - A comprehensive Analysis.
Practical
applications are discussed further on.
Exercise
Fever
A fever
refers to abnormally high body temperatures. This usually occurs in response to
invading microorganisms. Normal body temperature is 98.6 degrees F, however,
this increases in response to chemicals called pyrogens, secreted by
macrophages, and white blood cells exposed to bacteria and such like foreign
substances. This response is due to the fact that bacteria requires large
amounts of iron and zinc production to survive, but during a fever, the liver
and spleen minimize production of these nutrients, making them less accessible.
Additionally, fever speeds metabolic rate, increasing defensive actions and
repair processes. Commonly during a fever, heat loss from the body surface
declines, the skin becomes cool and shivering starts in order to generate heat.
This is known as the “chills,” a common sign of body temperature elevation. When
temperature rises to its new setting, it is then maintained there until body
defenses such as antibodies reverse the process back to a normal state. Once the
thermostat is set to normal, the sweat mechanism begins, and skin becomes warm,
a sign of decreased body temperature. Nervous system injuries, cancer, and
allergic reactions can cause a fever as well.
Now, during
exercise your body uses several thermoregulatory mechanisms such as sweat, and
blood flow. When this becomes ineffective, temperature increases, causing a
heightened metabolic rate, which further increases heat. Moreover, the skin
becomes dry and hot. As temperature continues to rise, this may lead to heat
stroke, a fatal condition in which brain damage can occur. This further supports
the reason behind adequate hydration.
Injury of
the nervous system can occur by water intoxification, a serious osmotic
unbalance caused by excessive water intake, with little electrolytes or other
foods. If you were to consume adequate amounts of water post-exercise but no
electrolytes, your plasma and ICF would become hypo osmotic (low osmolarity).
More water would move into your cells by osmoses to balance the ICF and ECF
osmolarity. This is primarily a problem for the central nervous system inside
your skull. The pressure buildup crowds the nervous system, causing dysfunctions
such as headaches, and even more life-threatening conditions. This may be why
the thirst mechanism does not promote complete liquid restoration, to limit
severe osmotic imbalances. This again supports the benefits of sodium
post-exercise, and in some scenarios, during.
Cramping
Cramping
refers to sustained spasms or large, painful contractions of muscles, lasting a
few seconds, minutes, or hours. Cramping causes the muscle to become hard, and
is quite agonizing. This may reflect low blood sugar levels, dehydration, and/or
electrolyte depletion. This again supports why workout nutrition is vital to
your health, and fitness goals. If you happen to cramp, I would look at these
three facets, and increase them immediately. Cramps may also be caused by spinal
cord neuron aggravations.
Practical
Applications
The
following recommendations are centered on water and sodium in pre, during, and
post-workout nutrition. For the complete package of exercise nutrition, you will
need to read
The Window of Opportunity and
Dextrose, Maltodextrin, and Sodium an In Depth Analysis.
Pre-Workout
Nutrition
About 500 ml of water
should be taken within 30 minutes of your workout [4, 20, 33]. This is to help
maintain a high gastric emptying rate, optimal pre-workout hydration, and
elevated plasma levels, ready to assist thermoregulation via sweating, and blood
flow.
During
Workout Nutrition
The ability for the body
to use ingested water depends on the rate of gastric emptying (the process of
digesting and emptying food out of the stomach). Gastric emptying is influenced
by fluid volume, caloric intake, and temperature. Only the first and last issues
need to be covered during this section.
Gastric emptying is
greatly influenced by its volume. Emptying rate decreases exponentially as fluid
volume is depleted. Therefore, an effective way to speed up gastric emptying is
by maintaining high fluid volumes in the stomach [8, 19, 27]. This will also
optimize nutrient passage into the intestines (discussed more next). When you
consume fluids, the rate of gastric emptying is speedy in the first few minutes,
and then steadily slows down. To prevent this, you should consume small amounts
of fluids frequently throughout your workout. Large amounts of water ingested
quickly (such as 600 ml) during exercise, often causes gastrial intestinal
distress. Around 400 ml of water can be cleared in 15 minutes for use, so with
this information, it is recommended to have 200-400 ml of water every 15 minutes
for ample hydration. [18, 34, 8].
Concerning fluid
temperature, it was thought previously that gastric rate was speeded by cold
beverages. Conversely, recent studies show the rate of digestion for cold and
hot beverages is primarily the same [19]. Cold drinks are often preferred
because they taste better, but a cold fluid does not add heat to the body, while
a hot liquid does. As such, it has been suggested to keep your fluids at 59-72
degrees F [8].
During exercise lasting
longer than 90 minutes, adding 500 mg of sodium per liter of water has been
recommended [8, 19, 33].
Post-Workout Nutrition
Post-exercise
supplementation is vital. Several nutrients must be consumed in this short
period of time such as glucose, maltodextrin, and whey protein. The problem is,
the more calories consumed, the slower gastric emptying is. However, having
between a 2.5-10% carbohydrate solution has been shown to be almost equivalent
in gastric emptying rate to just plain water [27, 9, 19]. Moreover, the glucose
sodium co transport system greatly increases fluid absorption compared to plain
water, as discussed previously. An additional 500 mg of sodium per liter of
water should be ingested [8, 33, 18], and a 92% water solution
(including carbohydrates and proteins). So, following the window of opportunity
journal entry, a man with 200 pounds of LBM cutting would have 50 grams of
protein, 50 grams of carbohydrates, 550 mg of sodium, and 1,250 milliliters of
water post-workout.
Conclusion
As you see, staying
properly hydrated takes hard work and extreme dedication. But what if I told you
that you would never have to thirst again? And what if I told you this was for
free? Only a fool would refuse such an offer! Thankfully, this gift is
available--and all you have to do is accept it [1].
John 4:13-14
13 Jesus answered and said
unto her, Whosoever drinketh of this water shall thirst again: 14 But whosoever
drinketh of the water that I shall give him shall never thirst; but the water
that I shall give him shall be in him a well of water springing up into
everlasting life.
John 6:35
35 And Jesus said unto
them, I am the bread of life: he that cometh to me shall never hunger; and he
that believeth on me shall never thirst.
Revelation 22:17
17 And the Spirit and the
bride say, Come. And let him that heareth say, Come.
And let him that is
athirst come. And whosoever will, let him take the water of life freely.
Keep it Hardcore,
Venom
Executive of Bioenergetic
Research
Venom@abcbodybuilding.com
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