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Strength Training Equipment
The purpose of the following article is to educate
readers on the different approaches to strength training.
Strength Training Exercises
Strength training is the use of resistance to muscular contraction
to build the strength, anaerobic endurance and size of skeletal muscles.
There are many different methods of strength training, the most common
being the use of gravity or elastic/hydraulic forces to oppose muscle
contraction. See the resistance training article for information about
elastic/hydraulic training, but note that the terms "strength training"
and "resistance training" are often used interchangeably.
When properly performed, strength training can provide significant
functional benefits and improvement in overall health and well-being
including increased bone, muscle, tendon and ligament strength and
toughness, improved joint function, reduced potential for injury,
increased bone density, a temporary increase in metabolism, improved
cardiac function and elevated good cholesterol. Training commonly uses
the technique of progressively increasing the force output of the muscle
through incremental increases of weight, elastic tension or other
resistance, and uses a variety of exercises and types of equipment to
target specific muscle groups. Strength training is primarily an
anaerobic activity, although some proponents have adapted it to provide
the benefits of aerobic exercise through circuit training.
Strength training differs from bodybuilding, weightlifting, powerlifting
and strongman, which are sports rather than forms of exercise, although
training for them is inherently interconnected with strength training,
as is also the case with throwing sports such as shotput and discus, and
Highland games. Many other sports often use strength training as part of
their training regimen, notably football, hockey and track and field,
but also baseball, downhill skiing, bobsleigh, lacrosse, swimming and
Until the 20th century, the history of strength
training was essentially a history of weight training.(
Shop for Weights.) With the advent of
modern technology, materials and knowledge, the methods that can be used
for strength training have multiplied significantly.
|Hippocrates explained the
principle behind strength training when he wrote "that which is used
develops, and that which is not used wastes away", referring to
muscular hypertrophy and atrophy. Progressive resistance training
dates back at least to Ancient Greece, when legend has it that
wrestler Milo of Croton trained by carrying a newborn calf on his back
every day until it was fully grown. Another Greek, the physician
Galen, described strength training exercises using the halteres (an
early form of dumbbell) in the 2nd century. Ancient Persians used the
meels, which became popular during the 19th century as the Indian
club, and has recently made a comeback in the form of the clubbell.
dumbbell was joined by the barbell in the latter half of the 19th
century. Early barbells had hollow globes that could be filled with
sand or lead shot, but by the end of the century these were replaced
by the plate-loading barbell commonly used today.
Strength training with isometric exercise was
popularized by Charles Atlas from the 1930s onwards. The 1960s saw the
gradual introduction of exercise machines into the still-rare strength
training gyms of the time. Strength training became increasingly
popular in the 1980s following the release of the bodybuilding movie
Pumping Iron and the subsequent popularity of
Since the late 1990s increasing numbers of women have taken up
strength training, influenced by programs like Body for Life;
currently nearly one in five U.S. women engages in weight training on
a regular basis.
Types of strength training
Weight and resistance training are popular methods of strength training
that use gravity (through weight stacks, plates or dumbbells) or
elastic/hydraulic resistance respectively to oppose muscle contraction.
Each method provides a different challenge to the muscle relating to the
position where the resistance to muscle contraction peaks. Weight training
provides the majority of the resistance at the initiating joint angle when
the movement begins, when the muscle must overcome the inertia of the
weight's mass (however, if repetitions are performed extremely slowly,
inertia is never overcome and resistance remains constant). In contrast,
elastic resistance provides the greatest opposition to contraction at the
end of the movement when the material experiences the greatest tension
while hydraulic resistance varies depending on the speed of the submerged
limb, with greater resistance at higher speeds. In addition to the
equipment used, joint angles can alter the force output of the muscles due
to leverage and the relative overlap of actin and myosin contractile
Resistance training is a form of strength training in which each effort is
performed against a specific opposing force generated by resistance (i.e.
resistance to being pushed, squeezed, stretched or bent). Exercises are
isotonic if a body part is moving against the force. Exercises are
isometric if a body part is holding still against the force. Resistance
exercise is used to develop the strength and size of skeletal muscles.
Properly performed, resistance training can provide significant functional
benefits and improvement in overall health and well-being.
The goal of resistance training, according to the American Sports Medicine
Institute (ASMI), is to "gradually and progressively overload the
musculoskeletal system so it gets stronger." Research shows that regular
resistance training will strengthen and tone muscles and increase bone
Isometric exercise, or "isometrics", is a type of strength training in
which the joint angle and muscle length do not change during contraction.
Isometric exercises are opposed by a force equal to the force output of
the muscle and there is no net movement. This mainly strengthens the
muscle at the specific joint angle at which the isometric exercise occurs,
with some increases in strength at joint angles up to 20° in either
direction depending on the joint trained. In comparison, isotonic
exercises strengthen the muscle throughout the entire range of motion of
the exercise used.
The basic principles of strength training involve a manipulation of the
number of repetitions (reps), sets, tempo, exercises and force to cause
desired changes in strength, endurance, size or shape by overloading of a
group of muscles. The specific combinations of reps, sets, exercises,
resistance and force depend on the purpose of the individual performing
the exercise: sets with fewer reps can be performed using more force, but
have a reduced impact on endurance.
Strength training also requires the use of 'good form', performing the
movements with the appropriate muscle group(s), and not transferring the
weight to different body parts in order to move greater weight/resistance
(called 'cheating'). Failure to use good form during a training set can
result in injury or an inability to meet training goals - since the
desired muscle group is not challenged sufficiently, the threshold of
overload is never reached and the muscle does not gain in strength.
The benefits of strength training include increased muscle, tendon and
ligament strength, bone density, flexibility, tone, metabolic rate and
Strength training has a variety of specialized terms used to describe
parameters of strength training:
* Exercise - different exercises involve moving joints in specific
patterns to challenge muscles in different ways
* Form - each exercise has a specific form, a topography of movement
designed to maximize safety and muscle strength gains
* Rep - short for repetition, a rep is a single cycle of lifting and
lowering a weight in a controlled manner, moving through the form of the
* Set - a set consists of several repetitions performed one after another
with no break between them with the number of reps per set and sets per
exercise depending on the goal of the individual. The number of
repetitions one can perform at a certain weight is called the Rep Maximum
(RM). For example, if one could perform ten reps at 75 lbs, then their RM
for that weight would be 10RM. 1RM is therefore the maximum weight that
someone can lift in a given exercise - i.e. a weight that they can only
lift once without a break.
* Tempo - the speed with which an exercise is performed; the tempo of a
movement has implications for the weight that can be moved and the effects
on the muscle.
Realization of training goals
According to popular theory:
* Sets of one to five repetitions primarily develop strength, with less
impact on muscle size and none on endurance.
* Sets of six to twelve repetitions develop a balance of strength, muscle
size and endurance.
* Sets of thirteen to twenty repetitions develop endurance, with some
increases to muscle size and limited impact on strength.
* Sets of more than twenty repetitions are considered to be focused on
aerobic exercise. They do still use the anaerobic system, but usually at a
rate through which it can consistently remove the lactic acid generated
Individuals typically perform one to six sets per exercise, and one to
three exercises per muscle group, with short breaks between each set - the
specific combinations of reps, exercises, sets and break duration depends
on the goals of the individual program. The duration of these breaks
determines which energy system the body utilizes. Performing a series of
exercises with little or no rest between them, referred to as "circuit
training", will draw energy mostly from the aerobic energy system. Brief
bursts of exercise, separated by breaks, are fueled by anaerobic systems,
which use either phosphagens or glycolysis.
For developing endurance, gradual increases in volume and gradual
decreases in intensity is the most effective program.
It has been shown that for beginners, multiple-set training offers minimal
benefits over single-set training with respect to either strength gain or
muscle mass increase, but for the experienced athlete multiple-set systems
are required for optimal progress. However, one study shows that for leg
muscles, three sets are more effective than one set.
Beginning weight-trainers are in the process of training the neurological
aspects of strength, the ability of the brain to generate a rate of
neuronal action potentials that will produce a muscular contraction that
is close to the maximum of the muscle's potential.
Weights for each exercise should be chosen so that
the desired number of repetitions can just be achieved.
In one common method, weight training uses the principle of progressive
overload, in which the muscles are overloaded by attempting to lift at
least as much weight as they are capable of. They respond by growing
larger and stronger. This procedure is repeated with progressively heavier
weights as the practitioner gains strength and endurance.
However, performing exercises at the absolute limit of one's strength
(known as one rep max lifts) is considered too risky for all but the most
experienced practitioners. Moreover, most individuals wish to develop a
combination of strength, endurance and muscle size. One repetition sets
are not well suited to these aims. Practitioners therefore lift lighter
(sub-maximal) weights, with more repetitions, to fatigue the muscle and
all fibres within that muscle as required by the progressive overload
Commonly, each exercise is continued to the point of momentary muscular
failure. Contrary to widespread belief, this is not the point at which the
individual thinks they cannot complete any more repetitions, but rather
the first repetition that fails due to inadequate muscular strength.
Training to failure is a controversial topic with some advocating training
to failure on all sets while others believe that this will lead to
overtraining, and suggest training to failure only on the last set of an
exercise. Some practitioners recommend finishing a set of repetitions just
before the point of failure; e.g. if you can do a maximum of 12 reps with
a given weight, only perform 11. Adrenaline and other hormones may promote
additional intensity by stimulating the body to lift additional weight (as
well as the neuro-muscular stimulations that happen when in
“fight-or-flight” mode, as the body activates more muscle fibres), so
getting "psyched up" before a workout can increase the maximum weight
Weight training can be a very effective form of strength training because
exercises can be chosen, and weights precisely adjusted, to safely exhaust
each individual muscle group after the specific numbers of sets and
repetitions that have been found to be the most effective for the
individual. Other strength training exercises lack the flexibility and
precision that weights offer.
Split training involves working no more than two or three muscle groups or
body parts per day, instead spreading the training of specific body parts
throughout a training cycle of several days. It is commonly used by more
advanced practitioners due to the logistics involved in training all
muscle groups maximally. Training all the muscles in the body individually
through their full range of motion in a single day is generally not
considered possible due to caloric and time constraints. Split training
involves fully exhausting individual muscle groups during a workout, then
allowing several days for the muscle to fully recover. Muscles are worked
roughly twice per week and allowed roughly 72 hours to recover. Recovery
of certain muscle groups is usually achieved on days while training other
groups. I.e. a 7 day week can consist of a practitioner training
trapezious, side shoulders and upper shoulders to exhaustion on one day,
the following day the arms to exhaustion, the day after that the rear,
front shoulders and back, the day after that the chest. In this way all
mentioned muscle groups are allowed the necessary recovery.
Intensity, volume, and frequency
Three important variables of strength training are intensity, volume and
frequency. Intensity refers to the amount of work required to achieve the
activity, and is proportional to the mass of the weights being lifted.
Volume refers to the number of muscles worked, exercises, sets and reps
during a single session. Frequency refers to how many training sessions
are performed per week.
These variables are important because they are all mutually conflicting,
as the muscle only has so much strength and endurance, and takes time to
recover due to microtrauma. Increasing one by any significant amount
necessitates the decrease of the other two, eg. increasing weight means a
reduction of reps, and will require more recovery time and therefore fewer
workouts per week. Trying to push too much intensity, volume and frequency
will result in overtraining, and eventually lead to injury and other
health issues such as chronic soreness and general lethargy, illness or
even acute trauma such as avulsion fractures. A high-medium-low formula
can be used to avoid overtraining, with either intensity, volume, or
frequency being high, one of the others being medium, and the other being
low. One example of this training strategy can be found in the following
|Intensity (% of
A common training strategy is to set the volume and
frequency the same each week (eg. training 3 times per week, with 2 sets
of 12 reps each workout), and steadily increase the intensity (weight) on
a weekly basis. However, to maximize progress to specific goals,
individual programs may require different manipulations, such as
decreasing the weight, and increase volume or frequency.
Making program alterations on a daily basis (daily
undulating periodization) seems to be more efficient in eliciting strength
gains than doing so every 4 weeks (linear periodization), but for
beginners there are no differences between different periodization models.
Periodization is the modulating of volume and intensity over time, to both
stimulate gains and allow recovery. Commonly, volume is decreased during a
training cycle while intensity is increased. In this template, a lifter
would begin a training cycle with a higher rep range than he will finish
with. For example, a lifter might begin a training program performing sets
with 8 reps. Throughout the course of his/her training program, the lifter
will slowly increase the weight while slowly decreasing the reps. This is
enough time for the neuromuscular system to adapt and become more
For this example, the lifter has a 1 rep max of 225
||Peak Intensity(Last Set)
||% of 1 Rep Max(Last Set)
||95 lb x 8reps
||100 lb x 8reps
||110 lb x 8reps
||115 lb x 8reps
||120 lb x 8reps
||105 lb x 8reps
||110 lb x 7reps
||115 lb x 7reps
||125 lb x 7reps
||130 lb x 7reps
||110 lb x 7reps
||120 lb x 7reps
||125 lb x 6reps
||135 lb x 6reps
||140 lb x 6reps
||125 lb x 6reps
||130 lb x 6reps
||140 lb x 6reps
||145 lb x 5reps
||155 lb x 5reps
||130 lb x 5reps
||140 lb x 5reps
||150 lb x 5reps
||155 lb x 5reps
||165 lb x 4reps
||140 lb x 4reps
||150 lb x 4reps
||160 lb x 4reps
||165 lb x 4reps
||175 lb x 4reps
This is an example of periodization where the volume
decreases while the intensity and weight increases.
The benefits of weight training include greater
muscular strength, improved muscle tone and appearance, increased
endurance, enhanced bone density, and improved cardiovascular fitness.
Many people take up weight training to improve their physical
attractiveness. Most men can develop substantial muscles; most women lack
the testosterone to do this, but they can develop a firm, "toned" (see
below) physique, and they can increase their strength by the same
proportion as that achieved by men (but usually from a significantly lower
starting point).Ultimately an individual's genetics dictate the response
to weight training stimuli to some extent.
The body's basal metabolic rate increases with increases in muscle mass,
which promotes long-term fat loss and helps dieters avoid yo-yo dieting.
Moreover, intense workouts elevate the metabolism for several hours
following the workout, which also promotes fat loss.
Weight training also provides functional benefits. Stronger muscles
improve posture, provide better support for joints, and reduce the risk of
injury from everyday activities. Older people who take up weight training
can prevent some of the loss of muscle tissue that normally accompanies
aging—and even regain some functional strength—and by doing so become less
frail.They may be able to avoid some types of physical disability.
Weight-bearing exercise also helps to prevent osteoporosis. The benefits
of weight training for older people have been confirmed by studies of
people who began engaging in it even in their 80s and 90s.
Strength training is the key to maintaining good flexibility. It takes
your body parts through a full range of motion and if you use the right
technique, you will be able to develop strength throughout an entire range
of movement. The ability of the body to resist the stresses that can
result from an injury can be increased by obtaining a greater amount of
strength. That is true in the athletic world and it has its advantages in
performing everyday activities, such as lifting or carrying objects.
Strength contributes to the overall efficiency of the human body. Starting
a strength training program, means you have started a new lifestyle
because strength is reversible. It will decline if you do not continue to
obtain a strength stimulus throughout your entire life.
Stronger muscles improve performance in a variety of sports.
Sport-specific training routines are used by many competitors. These often
specify that the speed of muscle contraction during weight training should
be the same as that of the particular sport.
Though weight training can stimulate the cardiovascular system, many
exercise physiologists, based on their observation of maximal oxygen
uptake, argue that aerobics training is a better cardiovascular stimulus.
Central catheter monitoring during resistance training reveals increased
cardiac output, suggesting that strength training shows potential for
cardiovascular exercise. However, a 2007 meta-analysis found that, though
aerobic training is an effective therapy for heart failure patients,
combined aerobic and strength training is ineffective.
One side-effect of any intense exercise is increased levels of dopamine,
serotonin and norepinephrine, which can help to improve mood and counter
feelings of depression
Bodybuilding is a sport in which the goal is to increase muscle size and
definition. Famous competitors include
Lou Ferrigno and
Ronnie Coleman. Bodybuilding increases
the endurance of muscles, as well as strength, though not as much as if it
were the primary goal. Bodybuilders compete in bodybuilding competitions,
and use specific principles and methods of strength training to maximize
muscular size and develop extremely low levels of body fat. In contrast,
most strength trainers train to improve their strength and endurance while
not giving special attention to reducing body fat below normal. Strength
trainers tend to focus on compound exercises to build basic strength,
whereas bodybuilders often use isolation exercises to visually separate
their muscles, and to improve muscular symmetry. Pre-contest training for
bodybuilders is different again, in that they attempt to retain as much
muscular tissue as possible while undergoing severe dieting. However, the
bodybuilding community has been the source of many strength training
principles, techniques, vocabulary, and customs.
Bodybuilding, strongman competitions and other sports are illustrations of
how the basic principles and methods of strength training can be applied
to achieve very different goals.
Lou Ferrigno's Guide to Personal Power,
Bodybuilding, and Fitness
It is widely accepted that strength training must be matched by changes in
diet in order to be effective. Adequate
protein is generally believed to
be required for building skeletal muscle with popular sources advising
weight trainers to consume a high protein diet with from 1.4 to 3.3 g of
protein per kg of body weight per day (0.6 to 1.5 g per pound). Protein
that is neither needed for cell growth and repair nor consumed for energy
is converted by the liver into fat, which is then stored in the body. Some
people believe that a high protein diet entails risk of kidney damage, but
studies have shown that kidney problems only occur in people with previous
kidney disease. Nonetheless, the deamination process creates urea, which
places low, but consistent, strain on the nephrons. Failure to properly
hydrate can result in an exaggeration of this effect. An adequate
supply of carbohydrates (5-7g per kg) is also needed as a source of energy
and for the body to restore glycogen levels in muscles.
A light, balanced meal prior to the workout (usually one to two hours
beforehand) ensures that adequate energy and amino acids are available for
the intense bout of exercise. Water is consumed throughout the course of
the workout to prevent poor performance due to dehydration.A protein shake
is often consumed immediately following the workout, because both protein
uptake and protein usage are increased at this time. Glucose (or another
simple sugar) is often consumed as well since this quickly replenishes any
glycogen lost during the exercise period. To maximize muscle protein
anabolism, recovery drink should contain glucose (dextrose), protein
(usually whey) hydrosylate containing mainly dipeptides and tripeptides,
Sex differences in mass gains
Due to the androgenic hormonal differences between males and females, the
latter are generally unable to develop large muscles regardless of the
training program used. Normally the most that can be achieved is a look
similar to that of a fitness model. Muscle is denser than fat, so someone
who builds muscle while keeping the same body weight will occupy less
volume; if two people weigh the same but have different lean body mass
percentages, the one with more muscle will appear thinner.
The results obtained by female bodybuilders are extremely atypical: they
are self-selected for their genetic ability to build muscle, perform
enormous amounts of exercise, their musculature is exaggerated by very low
body fat. Unless a woman dedicates her life to bodybuilding, she will not
achieve the same results as a professional male bodybuilder. In addition,
though bodybuilding uses the same principles as strength training, it is
with a goal of gaining muscle bulk. Strength trainers with different goals
and programs will not gain the same mass as a male professional
Some weight trainers perform light, high-repetition exercises in an
attempt to "tone" their muscles without increasing their size. The use of
the word "tone" in this sense is inaccurate. Muscle tone correctly refers
to the constant, low-frequency contractions that occur in all muscles,
even at "rest", to prepare them for future activity.
What muscle builders refer to as a toned physique is one that combines
reasonable muscular size with moderate levels of body fat, qualities that
may result from a combination of diet and exercise. High-repetition
exercises indeed do cause hypertrophy of both slow-twitch and high-twitch
muscle fibers, contributing to overall increased muscle bulk.
Dieting has no effect on muscle hypertrophy of any type of muscle fiber.
It may however decrease the thickness of the subcutaneous fat between
muscle and skin, through an overall reduction in body fat, thus making
muscle striations more visible.
Safety concerns related to children
Orthopaedic specialists used to recommend that children avoid weight
training because the growth plates on their bones might be at risk. The
very rare reports of growth plate fractures in children who trained with
weights occurred as a result of inadequate supervision, improper form or
excess weight, and there have been no reports of injuries to growth plates
in youth training programs that followed established guidelines. The
position of the National Strength and Conditioning Association is that
strength training is safe for children if properly designed and
Younger children are at greater risk of injury than adults should they
drop a weight on themselves or perform an exercise incorrectly; further,
they may lack understanding of, or ignore the safety precautions around
weight training equipment. Safer alternatives for children include the use
of sandbags or a lightly loaded weight vest. As a result, supervision of
minors is considered vital to ensuring the safety of any youth engaging in
An exercise like sit-ups or
abdominal crunches uses a much smaller volume
of muscle than whole-body aerobic exercise and is therefore less efficient
at burning calories than an exercise like jogging. Instead, high
weight/low rep exercises can be used to maintain or increase the body's
muscle mass while dieting. This helps to prevent the metabolic slowdown
that otherwise often limits the effect of dieting and causes post-diet
This too depends on the type of strength training utilized. Because weight
training generally is used for bulking, this bulking method will more than
likely increase weight because of the diet involved. However, when
resistance or circuit training is used, because it is not geared towards
bulking, women tend to lose weight more quickly. Lean muscle requires
calories to maintain itself at rest, which will help reduce fat through
the Basal Metabolic Rate.
Strength training can be a safe form of exercising, however each category
has it advantages as well as disadvantages. Weight training can be one of
the safest forms of exercise, especially when the movements are performed
correctly. However, as with any form of exercise, improper execution can
result in injury. When the trainee becomes fatigued, technique can break
down. For example, the deadlift allows heavy weights to be lifted with
correct technique. If the lower back fatigues and is allowed to round, the
resulting uneven spinal loading can cause disk compression injuries.
An exercise should be halted if marked or sudden
pain is felt, to prevent further injury. However, not all discomfort
indicates injury. Weight training exercises are brief but very intense,
and many people are unaccustomed to this level of effort. The expression
"no pain, no gain" refers to the discomfort expected from such vigorous
effort. It does not suggest ignoring the more severe pain that comes from
Discomfort can arise from other factors. Individuals who perform large
numbers of repetitions, sets and exercises for each muscle group may
experience lactic acid build-up in their muscles, which, contrary to
popular belief, is not the cause of the harmless burning sensation in the
muscles. These individuals may also experience a swelling sensation in
their muscles from increased blood flow (the "pump"), which is also
Beginners are advised to build up slowly to a weight training program.
Untrained individuals may have some muscles that are comparatively
stronger than others. An injury can result if, in a particular exercise,
the primary muscle is stronger than its stabilising muscles. Building up
slowly allows muscles time to develop appropriate strengths relative to
each other. This can also help to minimize delayed onset muscle soreness.
A sudden start to an intense program can cause significant muscular
soreness. Unexercised muscles contain cross-linkages that are torn during
Weight trainers commonly spend 5 to 20 minutes
warming up their muscles with
aerobic exercise before starting a workout.
They also stretch muscles after they have been exercised. The exercises
are performed at a steady pace, taking at least two to four seconds to
lift and lower the weight, to avoid jerks that can damage muscles and
Exercises where a barbell is held above the body, such as the squat or the
bench press, are normally performed inside a squat cage, which can catch
the bar, or in the presence of one or more spotters, who can safely
re-rack the barbell at the end of the set if the weight trainer is unable
to do so.
Anyone beginning an intensive physical training program is typically
advised to consult a physician, because of possible undetected heart or
other conditions for which such activity is contraindicated.
There have been mixed reviews regarding the use of
weightlifting belts and
other devices, such as
lifting straps. Critics claim that they allow the
lifter to use more weight than they 'should'. Using a belt is more
controversial as it does not prepare people for real situations, as they
do not normally wear lifting belts when performing real-life tasks. This
can lead to inadequate intra-abdominal pressure and torso/lower back
stabilization ability. Some criticize that the gripping muscles in the
forearms receive less benefit from the deadlift when using straps. This is
not a concern to people who do other exercises for forearm development, or
who are not concerned with forearm development. Strap-like implements are
commonly used in real-life deadlifting situations, and in many cases
weights are levered against the body or sandwiched between the arms, so
that not as much gripping strength is used anyway.
Types of exercises
Isotonic, isometric and plyometric exercises
These terms combine the prefix "iso" (meaning "same") with "tonic"
(strength) and "metric" (distance). In "isotonic" exercises the force
applied to the muscle does not change, and in "isometric" exercises the
length of the muscle does not change.
Weight training is primarily an isotonic form of exercise, because the
muscles are used to push or pull weighted objects. Any object can be used
for weight training, but dumbbells, barbells and other specialized
equipment are normally used because they can be adjusted to specific
weights, and are easily gripped. However, some exercises are not strictly
isotonic because the force on the muscle varies as the joint moves through
its range of motion, even though the force of the exercise remains
Some forms of weight training use isometric contractions to further stress
the muscles after or during a period of isotonic exercise. In this case
the muscles flex and hold a stationary position, and no movement of a load
Another form of training that often uses weights has a different goal.
Plyometric exercises exploit the stretch-shortening cycle of muscles to
enhance the myotatic (stretch) reflex. This involves rapid alternation of
lengthening and shortening of muscle fibers against a resistance. The
resistance involved is often a weighted object such as a medicine ball,
but can also be the body itself as in jumping exercises or the body with a
weight vest that allows movement such as the Hyper Vest. Plyometrics is
used to develop explosive speed, and focuses on power instead of maximal
strength, and may be used to improve the effectiveness of a boxer's punch,
for example, or to increase the vertical jumping ability of a basketball
Isolation exercises versus compound exercises
An isolation exercise is one where the movement is restricted to one
joint. For example, the leg extension is an isolation exercise for the
quadriceps. The other muscle groups are only minimally involved—they just
help the individual maintain a stable posture—and movement occurs only
around the knee joint. Other examples are the straight-legged deadlift
(hip extension) and the dumbbell/barbell curl (elbow flexion).
Compound exercises work several muscle groups at
once, and include movement around two or more joints. For example, in the
leg press movement occurs around the hip, knee and ankle joints. This
exercise is primarily used to develop the quadriceps, but it also involves
the hamstrings, glutes and calves.
Compound exercises are generally similar to the ways that people naturally
push, pull and lift objects, whereas isolation exercises often feel a
Each type of exercise has its uses. Compound exercises build the basic
strength that is needed to perform everyday pushing, pulling and lifting
activities. Isolation exercises are useful for "rounding out" a routine,
by directly exercising muscle groups that cannot be fully exercised in the
The type of exercise performed also depends on the individual's goals.
Those who seek to increase their performance in sports would focus mostly
on compound exercises, with isolation exercises being used to strengthen
just those muscles that are holding the athlete back. Similarly, a
powerlifter would focus on the specific compound exercises that are
performed at powerlifting competitions. However, those who seek to improve
the look of their body without necessarily maximizing their strength gains
(including bodybuilders) would put more of an emphasis on isolation
There are a number of exercise machines and other equipment that are
commonly found in strength training facilities.
* Smith machines have a barbell constrained to move only in the vertical
* Cable machines consists of two weight stacks separated by 2.5 metres,
with cables running through adjustable pulleys (that can be fixed at any
height) to various types of handles
o A variation of a
cable machine is a wide-grip bar attached to a weight
stack and a seat, used specifically for pulldown exercises that train the
latissimus dorsi muscle
There are also exercise-specific weight machines such as the leg press. A
multi-gym includes a variety of exercise-specific mechanisms in one
Free weights include dumbbells, barbells and other
objects. Unlike some
exercise machines, they do not constrain users to
specific, fixed movements, and require more stabilization skills. It is
often argued that free weight exercises are superior for precisely this
reason. As exercise machines can prevent poor form, they are somewhat
safer than free weights for novice trainees. Moreover, since users need
not concentrate so much on maintaining good form, they can focus more on
the effort they are putting into the exercise. Many serious athletes,
bodybuilders and fitness enthusiasts prefer to train with free weights and
Marcy Diamond Elite Smith System with Linear
One limitation of many free weight exercises and exercise machines is that
the muscle is working maximally against gravity during only a small
portion of the lift. Some exercise-specific machines feature an oval cam
(first introduced by Nautilus) which varies the resistance so that the
resistance, and the muscle force required, remains constant throughout the
full range of motion of the exercise.
Some free weight exercises can be performed while sitting or lying on a
Swiss ball. This makes it more difficult to maintain good form, which
helps to exercise the deep torso muscles that are important for
maintaining a good posture.
Types of strength training
There are different ways to increase strength, each with its own goals,
equipment, methods and/or results.
* Isometric exercise
* Super Slow
* Martial arts
Apart from the obvious weights and resistance bands, there are a number of
other items of exercise equipment that can be used while or to compliment
Swiss balls or
* Levering weights like
Weighted clothing like a
Aerobic exercise versus anaerobic exercise
Strength training exercise is primarily anaerobic. Even while training at
a lower intensity (training loads of ~20-RM), anaerobic glycolysis is
still the major source of power, although aerobic metabolism makes a small
contribution. Weight training is commonly perceived as anaerobic
exercise, because one of the more common goals is to increase strength by
lifting heavy weights. Other goals such as rehabilitation, weight loss,
body shaping, and bodybuilding often use lower weights, adding aerobic
character to the exercise.
Except in the extremes, a muscle will fire fibres of both the aerobic or
anaerobic types on any given exercise, in varying ratio depending on the
load on the intensity of the contraction. This is known as the energy
system continuum. At higher loads, the muscle will recruit all muscle
fibres possible, both anaerobic ("fast-twitch") and aerobic
("slow-twitch"), in order to generate the most force. However, at maximum
load, the anaerobic processes contract so forcefully that the aerobic
fibers are completely shut out, and all work is done by the anaerobic
processes. Because the anaerobic muscle fibre uses its fuel faster than
the blood and intracellular restorative cycles can resupply it, the
maximum number of repetitions is limited. In the aerobic regime, the blood
and intracellular processes can maintain a supply of fuel and oxygen, and
continual repetition of the motion will not cause the muscle to fail.
Circuit weight training is a form of exercise that uses a number of weight
training exercise sets separated by short intervals. The cardiovascular
effort to recover from each set serves a function similar to an aerobic
exercise, but this is not the same as saying that a weight training set is
itself an aerobic process.
Exercises for specific muscle groups
Weight trainers commonly divide the body's individual muscles into ten
major muscle groups. These do not include the hip, neck and forearm
muscles, which are rarely trained in isolation.
The large muscles of the lower body are normally
trained before the smaller muscles of the upper body, because these first
exercises require more mental and physical energy. The core muscles of the
torso are trained before the shoulder and arm muscles that assist them.
Exercises often alternate between "pushing" and "pulling" movements to
allow their specific supporting muscles time to recover. The stabilizing
muscles in the waist should be trained last.