Introduction to biomechanics


Which is the Best Exercise Tool, High-tech Machines or Free Weights?

Which is the best exercise tool, high techneither of which barbells supply:6. Balanced
machines or free weights?You may find thisresistance: Resistance that is neither too
information laborious; however, it islight nor too heavy.7. Automatically variable
necessary to outline the differences betweenresistance: The resistance varies within the
high-tech and non-high tech equipment for therange-of-
purpose of producing maximum fitness in
minimum time.Much of the equipment on themotion and in accord with a particular
market is virtually useless. Only by knowingmuscle group's strength
the  basicpotential.8. Unrestricted
Speed-of-MovementAlthough it should be
principal of design and function - of notpossible to perform exercise movements at
only  the  human  body,  but also equipment,various  speeds  for
can one decide the most time efficient meanshigh intensity contractions, throwing the
to  exercise.  With  that  goal  in mind, weresistance  is  not  beneficial.  However,
offer the following:Once upon a time, theunrestricted speed of movement is a
horse was the fastest form of transportation.requirement. Barbells supply this requirement
If  one's  goal
was to get from point A to point B, theas does high-tech equipment.For best
horse was faster than walking.Those withoutresults, perform movements rather slowly. As
much time to waste took a horse, arrivingan  example:  the  positive
quickly  at  the  destination.
portion of the movement should take about 4
Others has walked and eventually reached theseconds,  the  negative  portion  about  4
destination.Presently, the fastest form of
transportation  is  a  jet  airplane.seconds (as a safe example).By controlling
the movement, the muscle is contracting
If one's goal is to get from the East Coastalways.  A  fast  speed  of
to  the West Coast, as quickly and safely as
movement to is potentially dangerous.It
possible, the airplane is the best choice.Socompounds the force. First at the sudden,
it is in the choosing between non high-techjerky  start.  Then  again,  as  the
exercise  equipment  and  high-tech
resistance bangs into a body part, at its
equipment.Non high-tech is today'sfinal  destination  point.
equivalent of the horse. High-tech equipment
is  today'sIf a muscle is not prepared for the
beginning sudden jerk, injury is a
equivalent of jets. This is not to claimpossibility.9. Resistance In The Fully
that, the proper use of free weights andContracted PositionUnless resistance exists
otherin the position of full muscular contraction,
it  is  impossible
non high-tech equipment cannot be
beneficial;  however, for maximum results into exercise a muscle through its full
range-of-motion. That is basic premise of
minimum time there is no comparison.Thefull-
functions of the human body demands you use
of  an  exercise  tool  design  thatrange exercise.Many but not all high tech
machines provide proper variable and balanced
includes certain biomechanical parameters
lacking  in  non  high-tech  equipment.
resistance, in the position of full muscular
Function dictates design.One major reason iscontraction.  Other  forms  of  exercise
the body stability provided by high tech
equipment.  We  are  alltools, such as barbells, do not. Therefore,
it  would  indicate  that  resistance is not
aware of the laws of force-counter force and
the  stresses  placed  on  the  body  duringsupplied full-range, only partial-range.
This lessens the exercise potential.For
exercise.The support supplied to the body,instance, in the two-arm curling motion using
when lying or sitting, during high techa  barbell,  there  is  no  affective
exercise,
resistance supplied to your biceps muscle in
helps stabilize the body, absorb counterthe fully contracted position.With properly
force,  and  allows  one  to  monitor  anddesigned high tech equipment, there is
resistance in this position.We already
maintain proper body position.This effectualunderstand that resistance, properly
eliminates unwanted stress to other bodysupplied,  is  the  key  to  maximum
segments  and  eliminates
results in exercise.10. Direct
injury during exercise.Free weights, whenResistanceWhen possible, resistance must
used with various benches and seats can helpexist directly to the muscle under
modify  some  ofcontraction  to
the problems associated with forceinsure best results. Two similar exercises
counter--force.  However,  not  as  well  aswe  can  compare  are  the  two-arm chinning
machines do.There are also many other bodilymovement and a high-tech pullover
requirements for productive exercise, whichmachine.When performing a two-arm chinning
onlymovement, you will provide resistance to the
properly designed high-tech equipment canlatissimus dorsi and biceps of the upper
provideBarbells were a quantum forward leap,body  (among  other  muscles).  During  the
because  they  allowed the basic requirement
movement,  the  biceps  will
of productive exercise: Resistance, to be
applied  to  a  contracting  muscle,  withfatigue before the larger, stronger back
muscles.Therefore, you would not exercise the
greater effectiveness than previouslylatissimus  dorsi  muscles  as  effectively,
existing tools.In truth, it does not matter
to a muscle if one is lifting a 50 pound sackbecause of the weak link.High tech pullover
of  sugar  or  amachines supply resistance of a higher
quality  to  the  latissimus
50 pound barbell. The major difference is
the comfort factor.Performing a barbelldorsi muscle groups. By removing the weak
exercise is easier. One major reason is onelink,  in  the  two  arms  chinning
can  grip  it  better
movement and applying the resistance pads to
than a sack of sugar. To the muscles doingthe  upper  arms  near  the  elbows'  one
the  work,  it  is  still  50  pounds.  The
works the back muscles thoroughly.When one
amount of resistance used determines thefails to continue movement, due to muscular
amount of muscle fibers contracted.Just asfatigue,  the  primary  muscles
barbells were a quantum leap, so is high-tech
equipment  when  compared  tofail, not a weaker link in the chain.11.
Full-Range ResistanceMuscle contraction
barbells. Application of resistance (theprovides movement of one or more body
basic  principle of progressive exercise andsegments.  These
pro-active physical therapy) improves to asegments have what can be termed a complete
contracting muscle.However, not all high-techor full-range possibility.Ideally, one should
equipment incorporates all the requirementsbe able to exercise a body segment through a
offull-range  of
maximum progress. Some of the requirements'movement. Naturally, an injury may prevent
one should consider are:Positive and Negativethis  from  happening;  however,  the  goal
ResistanceA properly designed exercise tool
MUST  provide  two  aspects  of  resistance.is too to improved full-range movement.This
requirement rotary form movement is the
Resistance provided as one lifts andhardest  to  visualize.  In  simple  terms,
resistance must be supplied as one lowers the
it is: Resistance moving on a common axis
with  a  body  segment  being  moved  by
resistance.Sometimes called concentric or
positive resistance, this aspect takes placemuscle contraction.One excellent invention
when  onein the history of exercise is a device called
the  cam.  It  is  a
is contracting or shortening a muscle.
Lowering  resistance  or eccentric, negativecam that allows the experienced of maximally
productive exercise.In simple terms, the
movement and takes place as one uncontractsfunction of a cam is as follows:A cam
or allows the muscle to lengthen.Along withredirects resistance, so it travels in the
positive and negative resistance potentials,same  strength  curve  as  the  exercised
the  ability  to  stretch  and
body segment. The resistance is re-directed
pre-stretch a muscle is essential with anto  travel  in  a  rotary  motion and in the
exercise tool.Pre-stretch and
StretchingStretching is pushing or pulling asame strength curve of the moving body
body part into a position temporarilysegment.  At  the  same  time the resistance
exceeding
is directly OPPOSITE the intended
the existing "normal" range of motion. Itmovement.This assures resistance, typically
relates to the angels of the joints, muscles,provided by a weight stack. The lifting of
the
and connective tissue.Pre-stretching takesweight stack takes place through either
place when a muscle moves into a position ofcables or chains attached to it.The cables or
increased  tensionchains attach to the cam system and as the
cam  rotates,  the  cables  or
just prior to the start of a positive
contraction. Pre-stretch has two effects thatchains wrap around the cam. The radius of
the cam that the chain wraps into varies.The
distance from the center mark of the cam
result in greater benefits:(1) The muscle isradius,  to  the  point  where  the  chain
elastic, just like a rubber band, and
stretching  it  slightly,  justtouches as it wraps, determines the varying
(and  supposed  balanced  resistance).
before movement, actually produces elastic
energy  that  can  be  used  in  theThe touching point of the chain is directly
opposite  the  direction  of  muscle
contraction and help you use more
resistance.contraction.Barbells and some other forms of
exercise equipment do not supply resistance
(2) Pre-stretch ignites a nervous systemin
stretch  reflex  that  calls upon additional
this manner. They supply resistance in a
muscle fibers, for use in the upcomingstraight  line  manner, always directly down
movementNow, we have established four
requirements for full range, maximallytoward the ground, always depending on
productivegravity.Effective resistance is when you are
moving the barbell vertically, directly
exercise. They are:1. Positive work: Liftingopposite
the resistance.2. Negative work: Lowering
resistance.3. Stretching: A slightthe pull of gravity.A cam changes
lengthening of a musclestraight-line resistance (gravity) into
groups.4. Pre-stretching: Takes place in arotational  resistance.  This
slightly extreme range just before the
stretch.allows the resistance to travel in a curve
always  pulling  directly  away  from  your
It must be done carefully and with minimal
speed.5. Balanced Resistance and Variablemovement.Because barbells and some exercise
ResistanceAs muscles contract and movemachines  can  meet  only  some  of  the
through a range of motion, they do so with
varyingrequirements we have listed, it follows that
high-tech  has  the  potential  to  improve
degrees of movement and strength potentials.
one's fitness results.The QUALITY of the
resistance is the final determining factor,
This is a natural consequence of musculardetermining  which
contraction and human movement.You are aware
it is possible to handle more resistance inexercise tool provides best
some  exercises  thanresults.Calisthenics and aerobic dance supply
minimal  resistance  (arm  legs,  torso, and
others. You may not be aware that as one
performs  an  exercise,  the  muscleslower body).Gymnastics type exercise can be
more productive because a larger body mass is
involved, are also changing strength levels
as they move.That's one reason why some
positions of a movement feel easier thanmoved; therefore more resistance is handled
others,by muscle groups.Barbells, pulleys and the
like are more productive than either of the
although the weight remains constant.Becausetwo  mentioned
muscles have a variable strength potential as
they  move,  it  logically  followsbecause, resistance adjusts according to
one's fitness level.The most effective method
that, the resistance should vary accordingof exercise are High-Tech Machines, because
to the actual muscle strength potential.Thisthey  meet
is termed automatically variable resistance
when  incorporated  into  a  high-techthe requirements of offering the primary
exercise  needs  of  the  body,  full-range
machine design. When referring to the
various  muscle  groups and varying strengthprogressive resistance.Author of numerous
books, and national magazine articles with
potentials, it is termed balancedappearances  on
resistance.High-Tech equipment should provide
automatically variable resistance andmany radio and television programs.Former
balancedProducer of Televison Programming for
Nautilus  Sports\Medical  Industries
resistance. The resistance should vary
automatically, and according to the strengthand former Regional Director of Northern
California  for  MedX  West Physical Testing
potential, as one move through a range of
motion.  With  barbells,  the  resistanceRehabilitation Equipment.Former owner of
numerous total fitness and physical therapy
does not vary.We have now established, twocenters.Former IFBB and AAU physique
more requirements for a superior exercisejudge.Former competitor and title winner in
tool,Strong Man Contests.Latest book: The Da Vinci
Fitness CodeVeteran U.



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