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- Mar 18, 2012
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Something of interest borrowed from a friend:
WORKOUTS:
As a bodybuilder, for Size, we are concerned on building type 2 muscle fibers
- fast twitch- short and intense
more fast twitch more size
we have type 2A and type 2B
2A is the first ones we use,
as we continue and hit the fail this is when 2B kicks in
2b is those reps near impossible to execute, but if You do, you will have more growth = Size
most people give up and dont stimulate 2b....
only rep out with 2A...
some aim for type I that lacks a lot on size properties and is more likely to be used with advanced slin intake and blow up doll...here it shines..
There Are Three Primary Muscle Fiber Types In Humans:
Type I - are referred to as "slow twitch oxidative" - characterized by low force/power/speed production and high endurance,
Type IIA - are "fast twitch oxidative" - fall in between
Type IIB - are "fast twitch glycolytic" - high force/power/speed production and low endurance,
As their names suggest, each type has very different functional characteristics.
6-12 reps is good, less reps like 6 reps are fine with compound movements
Consider
different muscles get different reps.
It depends on fiber content.
People say we need to 'shock' (surprise) the muscles.
No, you need progressive overload to grow.
It is a relatively simple concept;
Excess energy (calories and, to a lesser extent, body fat),
progressive training stimulus, and
elevated hormones proportional to your development.
So Stimulus>consistency>progress>manipulate based on results is best way to go.
Usually Bodybuilders increase sarcoplasm elasticity and full blown the cell (become bigger - expanded)
Powerlifters increase myofibrils inside of sarcoplasma/muscle cell.
Cell do not expand at first glance it "just" become Denser and denser inside the cell.
aka more solid fundation - real and functional muscle.
From here we can check that strenght it's more functional but it does not equal size.
It affect muscle cell in diferent way and to be a complete Athlete we must play with all factors.
just need to periodizate workout style and make the main goal physique > the main type of workout
Testosterone increases the percentage of
type II muscle fibers
at the expense of
type I fibers
as well as inducing hypertrophy (Increased cell volume and/or increased muscle contractile protein synthesis...anabolism)
Trenbolone alone or Halotestin and other non aromatising compounds will increase muscle contr?ctil protein (myofibrils)
but
in presence of Estrogen from Testosterone it will increase cell volume as well (sarcoplasma)
Growth Hormone can induce hyperplasia
(the splitting of existing muscle fibers to form new ones or the joining of satellite cells to create additional fibers and/or cell count)
and GH increases type I fiber counts or both type I and type II
in the presence of testosterone elevation as well.
Esterless Compounds and mainly if high in androgen, are great to elevate IGF1 levels.
Trenbolone is good on proliferation of Satelite Cells.
WORKOUT TIPS:
Calves are slow twitch muscle fibers for endurace same as abs and forearms.
these are muscles we use every day to function this is why the more frequent training.
The gastroc is primarily a fast-twitch muscle
The soleus is primarily a slow-twitch muscle
If you do calf work with straight legs, you work both the gastroc and soleus
If you do calf work with bent legs, you work only the soleus
When you bounce, the achilles tendon does much, if not most of the work and the calf does little
For calves sets of 75-100 reps 6-8 sets every day is what made them grow 1-2 inches a month
calves abs and forearms are mostly slow twitch which means long sets 25-100 reps daily mutliple sets 6-8
Now
We walk on or legs ed, this is why they respond to high volume shock.
We dont walk on our arms. we use out forearms for everything.
So basically:
Chest - presses build mass - lower volume 6-10 is fine or 8-12 press with chest.
not shoulders or arms here. heavy and low reps is the way to go but stretch and squeeze like no other.
Lats - higher volume 10-15 on pull downs/up except mass builder like bend over rows- 6-10...
thickening workouts are best route to grow, mainly rows, tons of rows and reverse ones as well.
widening will be good warm up (up to 25reps) to get it start, stretching with pull overs too, great way to set neuro muscle conection.
The trick with pulldowns is the archening of the back with puffed chest to engage the lats, then using hands as a stationary hook while elbows are pulled down to contract the lats.
on thickness, we should visualize the back as a book where we try to close the book (the lats).
most train back with way to much weight and poor form..
underhand on almost all exercise develop best the lower lats and make the illusion of a smaller waist while complements the low volume workout of b?ceps.
Shoulders - higher volume 10-15 mostly, Press can be mixed from 15-6reps and is great massbuilder.
I like upright rows too.
Posterior head can be very high rep, 2 exercises per workout and should be the first thing to start.
Like Rear Dumbell Raises 20-30reps to start then progressive heavier down to 8reps.
Reverse Pec Fly 20-12reps - last set a drop set to failure.
Heavy Military Press 12-6reps
Behind the Head Press - lighter weight perfect form but as heavy as possible, sometimes can be superset with dumbell press or Smith Machine Press or Convergent Press being last set drop set.
Upright rows then Lateral and or Front raises can be done both or alternated in periodizations.
but remember
everything hits the front delt, lat pulldown, bench press,dips even standing curl..
isolate and destroy the rear, then start your workout to increase the 3D.
Legs - Squats and Romanian DeadLift are great massbuilders.
Respond to both High and Lower volume 10-30 reps but Hams are more into 8-15reps.
Calves - High volume like mentioned.
Reps with raises standing are 15-20 failure 4-6 sets,
Once you get use to this walk in between sets on tippy toes then do your next set.
when used increase reps 25-35.. and so on.
Calves are usually 80% slow + 20% fast twitchs so i like 8 heavy reps followed by 16lighter reps perfect form.
when used i would start increasing only the 16reps, not the 8 heavy ones.
next thing would be training them 2-3 times a week when lagging.
Arms mix volume - I think Bicep responde to low volume but also responde well to intensity methods like drop set/super set but in low rep range, 10-6reps.
Heavy Curl or Hammer Curl with dumbells/barbell mainly then Scott or Cable Curl for intensity.
Triceps need mixed higher volume and high reps - warm it up well then heavy weight low reps.
Skull Crushers and Close Grip Press as mainly mass builders 6-12.
Pull down extension/ropes or similar heavy but higher reps like 15-20.
I hit Tricep First (bigger muscle and usually underdeveloped on most that are focused on Bi's..) and place those elbows tight/narrow to hit the long head, the bigger one - This is VERY important.
Abs - high mainly but some heavy low volume at the end when already fatigue
Forearms - high - same as calves. usually forearms are now days poorly developed cause athletes use straps. this is great to boost strenght on lifts cause it nules forearm action and hands/fingers will act as hook with increased grip power from straps..but it affects forearms development to a point.
forearms workouts are not much used on this days too but its a plus on a well balanced physique.
LAGGING MUSCLES
Need to be trained with no interference of auxiliar muscles being sored or neither after a heavy/intense workout day.
Advanceds will even undertrain other bodyparts when trying to bring proportions up and get well dialed.
then additional kcals and rest - basicaly heal and grow.
Now if we are just overdoing it, muscle will not heal and will not grow!
Most Pro's traing 4 times a week for growth - 2 days On / 1 day Off.
this is when caloric surplus is on, alongside more rest and higher Testosterone/Gh/Slin.
they also load and deload on workouts.
2-3 weeks training heavy with tons of basic compound movements - explosive lifts.
1 week deload and bet more on eccentric part of the movement and focus on isolation exercises.
This is kind of HIIT but applyed to workout instead of Cardio.
When prepping is where volume training is increased to every day, with addition and increase of cardio while kcals are being dropped and Testosterone is now getting to lower ranges since they are not growing now, just holding on muscle - making it more dense looking without increasing size while they are shredding fat and water.
Chemistry and workout type make this better
(see how workouts and compounds affect muscle cell myofibril-Density and sarcoplasm-Size)
Myofibrils
The myofibrils are the contractile components that allow for strength and the performance
of work. When the fiber is stimulated to contract, the myofibrils experience a contractile
shortening and their circumference is increased. Myofibrils are comprised of the contractile
proteins, actin and myosin, which actually slide over each other during contractions. Heavy,
intense, low repetition resistance training has its primary effect on the actin and myosin. In fact,
the process by which damaged actin and myosin are repaired is commonly known as hypertrophy
protein synthesis. During heavy resistance training, the damage to the actin and myosin can
be too extensive for complete repair, or it can be insufficient to stimulate adaptation. Therefore,
the controlled damage and repair of them is the key to optimizing myofibril growth. This
process can be likened to the repair of skin after being injured, resulting in scar tissue which is
much stronger than the original tissue. Muscle is the same. The end result is a much larger and
stronger myofibril component.
Mitochondria
The mitochondria are located all along the myofibrils. They provide the energy a cell needs
to move, divide, secrete and contract. They are commonly known as the powerhouses, or
power centers of the cell. They are about the size of bacteria, but may have different shapes
depending on the cell type. The mitochondria produce energy in the form of ATP, which is used
during contractions, for daily activity, and recovery energy needs. Through regular and intense
high repetition resistance training, the cell must adapt by building more mitochondria. This will
boost cellular energy storage and ATP production capacity.
Muscle Fiber Types
As mentioned there are three types of muscle tissue; white fast twitch, red fast twitch and red
slow twitch muscle fibers. These different fibers have exactly the same internal components,
but vary in number and size. They have differing levels of a substance called myosin-ATPase,
which breaks down ATP for energy. The more of this enzyme, the faster the contraction, thus
more power as well. These fiber types have varying cardiovascular support systems and fuelutilization
characteristics, and have different types of nerves that stimulate them. Therefore, they
are coordinated, or organized functionally, as well as structurally. The individual fiber is stimulated
to contract by a branch of the neuron called an axon, which varies in thickness and the degree of
myelination, or insulation it possesses. The thicker or more myelinated it is, the faster the signal
can travel down it. For highly efficient aerobic metabolism to occur, oxygen must be present.
This is delivered to the muscle cell by a very small tube called a capillary. Microscopic capillaries
extend throughout intramuscular areas surrounding the muscle fibers
Skeletal Muscle Tissue
Roughly 40% of body Structure of muscle cell
Elongated: length of muscle
Multiple flattened nuclei along outer portion near saracolemma
Consists of bundles of fibers (myofibrils)
Bundles of muscle fibers wrapped in connective tissue are called fasciculi
Nerve connection to muscle belly called motor end plate.
Myofibrils made of contractile proteins: actin (thin myofilaments) and myosin
(thick myofilaments)
Thin myofilaments also contain proteins troponin and tropomyosin which aid in contraction
Actin connected to myosin through cross bridges
Muscles that work together to produce a common movement: synergists
Muscles that produce opposing movements: antagonists
Muscle Contraction
Motor nerve cell (neuron) carries stimulus to motor end plate.
Acetylcholine crosses the neuromuscular junction and stimulates sarcolemma.
After acetylcholine reaches muscle fiber, it stimulates a release of calcium in the cell,
which triggers action of the troponin and tropomysin.
Cross bridges pull thick and thin myofilaments over each other, shortening the length of
entire fiber.
One neuron may innervate up to one hundred muscle fibers.
Motor unit: unit of muscle fibers innervated by one single neuron.
The less muscle fibers innervated by one neuron, the more fine control over the muscle
(fine movements).
Force is generated in two ways:
1) increasing the amount of motor units firing
2) increasing the speed of neuro-motor stimuli.
When a muscle is stimulated to work, it can only shorten.
Muscles pull on the objects they are connected to.
Concentric Contraction
Muscle contraction as fibers shorten.
Usually active, voluntary.
Eccentric Contraction
Muscles contract as fibers lengthen.
Usually involuntary, in order to protect the joint.
Usually antagonistic - purpose is to decelerate the agonist (this usually occurs at the end
range of the joint).
Strength training is more effective when includes eccentric actions.
More muscle injuries occur during eccentric than concentric phase.
Isotonic Contraction
Muscle contraction with movement around the joint.
Isometric Contraction
Muscle contraction with no movement around the joint.
Isokinetic Contraction
Muscle contraction at a constant velocity.
For example, pushing an object that cannot be moved.
Agonists
Muscle performing a particular action.
Antagonists
Muscles that act in opposition to the movement generated by the agonists.
Responsible for returning a limb to its initial position.
Reciprocal Inhibition (forced relaxation).
Inhibited from contracting due to tight agonists.
Antagonistic Muscle Groups
Pectorals/latissimus dorsi.
Anterior deltoids/posterior deltoids.
Left and right external obliques.Quadriceps/hamstrings.
Biceps/triceps.
Forearm flexors/extensors.
Synergists
Smaller muscles providing assistance to the larger working muscle groups.
Stabilizers
Muscles providing stability in order for the agonist to perform.
The individual fiber is stimulated to contract by a branch of the neuron called an axon. If
you could isolate and cut a cross section of an individual skeletal muscle cell fiber and look inside,
you would see that it consists of several components, each having a specific function. Your
training will be increase in productivity when you understand how to individually and intelligently
affect the cell function.
Connective Tissue and Blood Supply
The epimysium surrounds the entire muscle group with a sheath of connective, fibrous,
and elastic tissue. The sheath of connective tissue surrounding a bundle of muscles, or motor
unit, is called the perimysium, and the connective tissue surrounding each muscle cell fiber is the
endomysium. These different fibers have differing cardiovascular support systems. Microscopic
capillaries extend throughout intramuscular areas surrounding all of these muscle tissue fibers.
The white, fast twitch muscle fibers have very few capillaries, and in the absence of this nutrient
rich blood supply, they cannot function for very long periods, but are extremely strong. The red,
fast twitch muscle fibers have a greater number of capillaries, and can, therefore, outlast the
white, fast twitch fibers, but are not nearly as strong. The red, slow twitch muscle fibers have a
tremendous number of capillaries, allowing for long-term sustained activity, however, with very
little strength.
when you understand how to individually and intelligently
affect the cell function.
Motor units
A motor unit is a single motor neuron plus all the muscle fibers to which it connects.
Some motor neurons only connect to a few muscle fibers, while other motor neurons connect
to hundreds of muscle fibers. All the muscle fibers randomly occur together in small bundles
in genetically predetermined proportions. These bundles are called motor units and are named
after the predominant type of fibers located in these motor units. If a motor unit is made up of
predominantly white, fast twitch tissue fibers, that motor unit is called a white, fast twitch motor
unit, and so on.
Motor unit Function
Generally speaking, white, fast twitch motor units are responsible for speed and strength,
and a person who has a predominance of these would be best suited for strength events. The
red, fast twitch motor units are responsible for sustaining a load over prolonged periods, and
a person with a predominance of these motor units would be best suited for events requiring
stamina, such as boxing, football, basketball, and so on. The red, slow twitch motor unit is
responsible for producing energy over long periods, and a person with a predominance of these
would be best suited for endurance events
Myofibril Failure 4-6 Reps (Strength)
The second of these four types of failure occurs if the resistance is so great that the
contractile components fail prior to the depletion of available energy in the working muscles. These
near maximum contractions will call upon the immediate recruitment, damage, and growth of
existing myofibrils, especially in the white, fast twitch motor units. Well call this Myofibril Failure.
The optimum repetition range to use for this effect is the four to six repetition range
Frequent performance of sets using fewer repetitions to failure can result in acute or accumulative damage to soft tissues.
Intermediate Failure 12-15 Reps (Muscular Stamina)
The third of these four reasons for contractile failure occurs when the contractile
components are failing at, or about the same time as the short-term energy stores are depleted. This, in theory, will result in adaptation through the building of new myofibrils and mitochondria especially in the red, fast twitch motor units. We will call this type of failure Intermediate Failure. The optimum repetition range to use for this affect is 12 to 15 repetitions. Sets of about 7 to 11 repetitions call on the participation of both white and red, fast twitch motor units.
Mitochondrial Failure 20-25 Reps (Muscular Endurance)
The fourth contractile failure type occurs as a result of depleted energy stores, and
a subsequent accumulation of contraction inhibiting substances prior to causing any growth stimulating damage. This, in theory, will result in adaptation through the increased storage of
energy, and the building of new mitochondria, especially in the red, slow twitch motor units. This type of failure Mitochondrial Failure. The optimum repetition range to use for this affect is 20 to 25 repetitions. Performing sets of 16 to 19 repetitions will once again call on the varying involvement of the red, fast and the red slow twitch motor units.,
From: GHLR3
WORKOUTS:
As a bodybuilder, for Size, we are concerned on building type 2 muscle fibers
- fast twitch- short and intense
more fast twitch more size
we have type 2A and type 2B
2A is the first ones we use,
as we continue and hit the fail this is when 2B kicks in
2b is those reps near impossible to execute, but if You do, you will have more growth = Size
most people give up and dont stimulate 2b....
only rep out with 2A...
some aim for type I that lacks a lot on size properties and is more likely to be used with advanced slin intake and blow up doll...here it shines..
There Are Three Primary Muscle Fiber Types In Humans:
Type I - are referred to as "slow twitch oxidative" - characterized by low force/power/speed production and high endurance,
Type IIA - are "fast twitch oxidative" - fall in between
Type IIB - are "fast twitch glycolytic" - high force/power/speed production and low endurance,
As their names suggest, each type has very different functional characteristics.
6-12 reps is good, less reps like 6 reps are fine with compound movements
Consider
different muscles get different reps.
It depends on fiber content.
People say we need to 'shock' (surprise) the muscles.
No, you need progressive overload to grow.
It is a relatively simple concept;
Excess energy (calories and, to a lesser extent, body fat),
progressive training stimulus, and
elevated hormones proportional to your development.
So Stimulus>consistency>progress>manipulate based on results is best way to go.
Usually Bodybuilders increase sarcoplasm elasticity and full blown the cell (become bigger - expanded)
Powerlifters increase myofibrils inside of sarcoplasma/muscle cell.
Cell do not expand at first glance it "just" become Denser and denser inside the cell.
aka more solid fundation - real and functional muscle.
From here we can check that strenght it's more functional but it does not equal size.
It affect muscle cell in diferent way and to be a complete Athlete we must play with all factors.
just need to periodizate workout style and make the main goal physique > the main type of workout
Testosterone increases the percentage of
type II muscle fibers
at the expense of
type I fibers
as well as inducing hypertrophy (Increased cell volume and/or increased muscle contractile protein synthesis...anabolism)
Trenbolone alone or Halotestin and other non aromatising compounds will increase muscle contr?ctil protein (myofibrils)
but
in presence of Estrogen from Testosterone it will increase cell volume as well (sarcoplasma)
Growth Hormone can induce hyperplasia
(the splitting of existing muscle fibers to form new ones or the joining of satellite cells to create additional fibers and/or cell count)
and GH increases type I fiber counts or both type I and type II
in the presence of testosterone elevation as well.
Esterless Compounds and mainly if high in androgen, are great to elevate IGF1 levels.
Trenbolone is good on proliferation of Satelite Cells.
WORKOUT TIPS:
Calves are slow twitch muscle fibers for endurace same as abs and forearms.
these are muscles we use every day to function this is why the more frequent training.
The gastroc is primarily a fast-twitch muscle
The soleus is primarily a slow-twitch muscle
If you do calf work with straight legs, you work both the gastroc and soleus
If you do calf work with bent legs, you work only the soleus
When you bounce, the achilles tendon does much, if not most of the work and the calf does little
For calves sets of 75-100 reps 6-8 sets every day is what made them grow 1-2 inches a month
calves abs and forearms are mostly slow twitch which means long sets 25-100 reps daily mutliple sets 6-8
Now
We walk on or legs ed, this is why they respond to high volume shock.
We dont walk on our arms. we use out forearms for everything.
So basically:
Chest - presses build mass - lower volume 6-10 is fine or 8-12 press with chest.
not shoulders or arms here. heavy and low reps is the way to go but stretch and squeeze like no other.
Lats - higher volume 10-15 on pull downs/up except mass builder like bend over rows- 6-10...
thickening workouts are best route to grow, mainly rows, tons of rows and reverse ones as well.
widening will be good warm up (up to 25reps) to get it start, stretching with pull overs too, great way to set neuro muscle conection.
The trick with pulldowns is the archening of the back with puffed chest to engage the lats, then using hands as a stationary hook while elbows are pulled down to contract the lats.
on thickness, we should visualize the back as a book where we try to close the book (the lats).
most train back with way to much weight and poor form..
underhand on almost all exercise develop best the lower lats and make the illusion of a smaller waist while complements the low volume workout of b?ceps.
Shoulders - higher volume 10-15 mostly, Press can be mixed from 15-6reps and is great massbuilder.
I like upright rows too.
Posterior head can be very high rep, 2 exercises per workout and should be the first thing to start.
Like Rear Dumbell Raises 20-30reps to start then progressive heavier down to 8reps.
Reverse Pec Fly 20-12reps - last set a drop set to failure.
Heavy Military Press 12-6reps
Behind the Head Press - lighter weight perfect form but as heavy as possible, sometimes can be superset with dumbell press or Smith Machine Press or Convergent Press being last set drop set.
Upright rows then Lateral and or Front raises can be done both or alternated in periodizations.
but remember
everything hits the front delt, lat pulldown, bench press,dips even standing curl..
isolate and destroy the rear, then start your workout to increase the 3D.
Legs - Squats and Romanian DeadLift are great massbuilders.
Respond to both High and Lower volume 10-30 reps but Hams are more into 8-15reps.
Calves - High volume like mentioned.
Reps with raises standing are 15-20 failure 4-6 sets,
Once you get use to this walk in between sets on tippy toes then do your next set.
when used increase reps 25-35.. and so on.
Calves are usually 80% slow + 20% fast twitchs so i like 8 heavy reps followed by 16lighter reps perfect form.
when used i would start increasing only the 16reps, not the 8 heavy ones.
next thing would be training them 2-3 times a week when lagging.
Arms mix volume - I think Bicep responde to low volume but also responde well to intensity methods like drop set/super set but in low rep range, 10-6reps.
Heavy Curl or Hammer Curl with dumbells/barbell mainly then Scott or Cable Curl for intensity.
Triceps need mixed higher volume and high reps - warm it up well then heavy weight low reps.
Skull Crushers and Close Grip Press as mainly mass builders 6-12.
Pull down extension/ropes or similar heavy but higher reps like 15-20.
I hit Tricep First (bigger muscle and usually underdeveloped on most that are focused on Bi's..) and place those elbows tight/narrow to hit the long head, the bigger one - This is VERY important.
Abs - high mainly but some heavy low volume at the end when already fatigue
Forearms - high - same as calves. usually forearms are now days poorly developed cause athletes use straps. this is great to boost strenght on lifts cause it nules forearm action and hands/fingers will act as hook with increased grip power from straps..but it affects forearms development to a point.
forearms workouts are not much used on this days too but its a plus on a well balanced physique.
LAGGING MUSCLES
Need to be trained with no interference of auxiliar muscles being sored or neither after a heavy/intense workout day.
Advanceds will even undertrain other bodyparts when trying to bring proportions up and get well dialed.
then additional kcals and rest - basicaly heal and grow.
Now if we are just overdoing it, muscle will not heal and will not grow!
Most Pro's traing 4 times a week for growth - 2 days On / 1 day Off.
this is when caloric surplus is on, alongside more rest and higher Testosterone/Gh/Slin.
they also load and deload on workouts.
2-3 weeks training heavy with tons of basic compound movements - explosive lifts.
1 week deload and bet more on eccentric part of the movement and focus on isolation exercises.
This is kind of HIIT but applyed to workout instead of Cardio.
When prepping is where volume training is increased to every day, with addition and increase of cardio while kcals are being dropped and Testosterone is now getting to lower ranges since they are not growing now, just holding on muscle - making it more dense looking without increasing size while they are shredding fat and water.
Chemistry and workout type make this better
(see how workouts and compounds affect muscle cell myofibril-Density and sarcoplasm-Size)
Myofibrils
The myofibrils are the contractile components that allow for strength and the performance
of work. When the fiber is stimulated to contract, the myofibrils experience a contractile
shortening and their circumference is increased. Myofibrils are comprised of the contractile
proteins, actin and myosin, which actually slide over each other during contractions. Heavy,
intense, low repetition resistance training has its primary effect on the actin and myosin. In fact,
the process by which damaged actin and myosin are repaired is commonly known as hypertrophy
protein synthesis. During heavy resistance training, the damage to the actin and myosin can
be too extensive for complete repair, or it can be insufficient to stimulate adaptation. Therefore,
the controlled damage and repair of them is the key to optimizing myofibril growth. This
process can be likened to the repair of skin after being injured, resulting in scar tissue which is
much stronger than the original tissue. Muscle is the same. The end result is a much larger and
stronger myofibril component.
Mitochondria
The mitochondria are located all along the myofibrils. They provide the energy a cell needs
to move, divide, secrete and contract. They are commonly known as the powerhouses, or
power centers of the cell. They are about the size of bacteria, but may have different shapes
depending on the cell type. The mitochondria produce energy in the form of ATP, which is used
during contractions, for daily activity, and recovery energy needs. Through regular and intense
high repetition resistance training, the cell must adapt by building more mitochondria. This will
boost cellular energy storage and ATP production capacity.
Muscle Fiber Types
As mentioned there are three types of muscle tissue; white fast twitch, red fast twitch and red
slow twitch muscle fibers. These different fibers have exactly the same internal components,
but vary in number and size. They have differing levels of a substance called myosin-ATPase,
which breaks down ATP for energy. The more of this enzyme, the faster the contraction, thus
more power as well. These fiber types have varying cardiovascular support systems and fuelutilization
characteristics, and have different types of nerves that stimulate them. Therefore, they
are coordinated, or organized functionally, as well as structurally. The individual fiber is stimulated
to contract by a branch of the neuron called an axon, which varies in thickness and the degree of
myelination, or insulation it possesses. The thicker or more myelinated it is, the faster the signal
can travel down it. For highly efficient aerobic metabolism to occur, oxygen must be present.
This is delivered to the muscle cell by a very small tube called a capillary. Microscopic capillaries
extend throughout intramuscular areas surrounding the muscle fibers
Skeletal Muscle Tissue
Roughly 40% of body Structure of muscle cell
Elongated: length of muscle
Multiple flattened nuclei along outer portion near saracolemma
Consists of bundles of fibers (myofibrils)
Bundles of muscle fibers wrapped in connective tissue are called fasciculi
Nerve connection to muscle belly called motor end plate.
Myofibrils made of contractile proteins: actin (thin myofilaments) and myosin
(thick myofilaments)
Thin myofilaments also contain proteins troponin and tropomyosin which aid in contraction
Actin connected to myosin through cross bridges
Muscles that work together to produce a common movement: synergists
Muscles that produce opposing movements: antagonists
Muscle Contraction
Motor nerve cell (neuron) carries stimulus to motor end plate.
Acetylcholine crosses the neuromuscular junction and stimulates sarcolemma.
After acetylcholine reaches muscle fiber, it stimulates a release of calcium in the cell,
which triggers action of the troponin and tropomysin.
Cross bridges pull thick and thin myofilaments over each other, shortening the length of
entire fiber.
One neuron may innervate up to one hundred muscle fibers.
Motor unit: unit of muscle fibers innervated by one single neuron.
The less muscle fibers innervated by one neuron, the more fine control over the muscle
(fine movements).
Force is generated in two ways:
1) increasing the amount of motor units firing
2) increasing the speed of neuro-motor stimuli.
When a muscle is stimulated to work, it can only shorten.
Muscles pull on the objects they are connected to.
Concentric Contraction
Muscle contraction as fibers shorten.
Usually active, voluntary.
Eccentric Contraction
Muscles contract as fibers lengthen.
Usually involuntary, in order to protect the joint.
Usually antagonistic - purpose is to decelerate the agonist (this usually occurs at the end
range of the joint).
Strength training is more effective when includes eccentric actions.
More muscle injuries occur during eccentric than concentric phase.
Isotonic Contraction
Muscle contraction with movement around the joint.
Isometric Contraction
Muscle contraction with no movement around the joint.
Isokinetic Contraction
Muscle contraction at a constant velocity.
For example, pushing an object that cannot be moved.
Agonists
Muscle performing a particular action.
Antagonists
Muscles that act in opposition to the movement generated by the agonists.
Responsible for returning a limb to its initial position.
Reciprocal Inhibition (forced relaxation).
Inhibited from contracting due to tight agonists.
Antagonistic Muscle Groups
Pectorals/latissimus dorsi.
Anterior deltoids/posterior deltoids.
Left and right external obliques.Quadriceps/hamstrings.
Biceps/triceps.
Forearm flexors/extensors.
Synergists
Smaller muscles providing assistance to the larger working muscle groups.
Stabilizers
Muscles providing stability in order for the agonist to perform.
The individual fiber is stimulated to contract by a branch of the neuron called an axon. If
you could isolate and cut a cross section of an individual skeletal muscle cell fiber and look inside,
you would see that it consists of several components, each having a specific function. Your
training will be increase in productivity when you understand how to individually and intelligently
affect the cell function.
Connective Tissue and Blood Supply
The epimysium surrounds the entire muscle group with a sheath of connective, fibrous,
and elastic tissue. The sheath of connective tissue surrounding a bundle of muscles, or motor
unit, is called the perimysium, and the connective tissue surrounding each muscle cell fiber is the
endomysium. These different fibers have differing cardiovascular support systems. Microscopic
capillaries extend throughout intramuscular areas surrounding all of these muscle tissue fibers.
The white, fast twitch muscle fibers have very few capillaries, and in the absence of this nutrient
rich blood supply, they cannot function for very long periods, but are extremely strong. The red,
fast twitch muscle fibers have a greater number of capillaries, and can, therefore, outlast the
white, fast twitch fibers, but are not nearly as strong. The red, slow twitch muscle fibers have a
tremendous number of capillaries, allowing for long-term sustained activity, however, with very
little strength.
when you understand how to individually and intelligently
affect the cell function.
Motor units
A motor unit is a single motor neuron plus all the muscle fibers to which it connects.
Some motor neurons only connect to a few muscle fibers, while other motor neurons connect
to hundreds of muscle fibers. All the muscle fibers randomly occur together in small bundles
in genetically predetermined proportions. These bundles are called motor units and are named
after the predominant type of fibers located in these motor units. If a motor unit is made up of
predominantly white, fast twitch tissue fibers, that motor unit is called a white, fast twitch motor
unit, and so on.
Motor unit Function
Generally speaking, white, fast twitch motor units are responsible for speed and strength,
and a person who has a predominance of these would be best suited for strength events. The
red, fast twitch motor units are responsible for sustaining a load over prolonged periods, and
a person with a predominance of these motor units would be best suited for events requiring
stamina, such as boxing, football, basketball, and so on. The red, slow twitch motor unit is
responsible for producing energy over long periods, and a person with a predominance of these
would be best suited for endurance events
Myofibril Failure 4-6 Reps (Strength)
The second of these four types of failure occurs if the resistance is so great that the
contractile components fail prior to the depletion of available energy in the working muscles. These
near maximum contractions will call upon the immediate recruitment, damage, and growth of
existing myofibrils, especially in the white, fast twitch motor units. Well call this Myofibril Failure.
The optimum repetition range to use for this effect is the four to six repetition range
Frequent performance of sets using fewer repetitions to failure can result in acute or accumulative damage to soft tissues.
Intermediate Failure 12-15 Reps (Muscular Stamina)
The third of these four reasons for contractile failure occurs when the contractile
components are failing at, or about the same time as the short-term energy stores are depleted. This, in theory, will result in adaptation through the building of new myofibrils and mitochondria especially in the red, fast twitch motor units. We will call this type of failure Intermediate Failure. The optimum repetition range to use for this affect is 12 to 15 repetitions. Sets of about 7 to 11 repetitions call on the participation of both white and red, fast twitch motor units.
Mitochondrial Failure 20-25 Reps (Muscular Endurance)
The fourth contractile failure type occurs as a result of depleted energy stores, and
a subsequent accumulation of contraction inhibiting substances prior to causing any growth stimulating damage. This, in theory, will result in adaptation through the increased storage of
energy, and the building of new mitochondria, especially in the red, slow twitch motor units. This type of failure Mitochondrial Failure. The optimum repetition range to use for this affect is 20 to 25 repetitions. Performing sets of 16 to 19 repetitions will once again call on the varying involvement of the red, fast and the red slow twitch motor units.,
From: GHLR3
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