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Weight training

2007 Schools Wikipedia Selection. Related subjects: Health and medicine

   A complete weight training workout can be performed with a pair of
   adjustable dumbbells and a set of weight disks (plates).
   Enlarge
   A complete weight training workout can be performed with a pair of
   adjustable dumbbells and a set of weight disks (plates).

   Weight training is a form of exercise for developing the strength and
   size of skeletal muscles. It is a common type of strength training
   which uses the force of gravity (in the form of weighted bars, dumbells
   or weight stacks) to oppose the force generated by muscle through
   concentric or eccentric contraction.

   Properly performed, weight training can provide significant functional
   benefits and improvement in overall health and well-being including
   increased bone, muscle, tendon and ligament strength, improved joint
   function, reduced potential for injury, improved cardiac function and
   elevated good cholesterol. In one common training method, the technique
   involves lifting progressively increasing amounts of weight, and uses a
   variety of exercises and types of equipment to target specific muscle
   groups. Weight training is primarily an anaerobic activity, although
   some proponents have adapted it to provide the benefits of aerobic
   exercise.

   Weight training differs from bodybuilding, weightlifting, and
   powerlifting, which are sports rather than forms of exercise. Weight
   training, however, is often part of their training regimen.

History

   An early plate-loading barbell and kettlebell
   Enlarge
   An early plate-loading barbell and kettlebell

   Hippocrates explained the principle behind weight training when he
   wrote "that which is used develops, and that which is not used wastes
   away." 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.

   Another early device was the Indian club, which came from ancient
   Persia where it was called the "meels." It subsequently became popular
   during the 19th century, and has recently made a comeback in the form
   of the clubbell.

   The 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.

   The 1960s saw the gradual introduction of exercise machines into the
   still-rare strength training gyms of the time. Weight training became
   increasingly popular in the 1980s, following the release of the
   bodybuilding movie Pumping Iron and the subsequent popularity of Arnold
   Schwarzenegger. Since the late 1990s increasing numbers of women have
   taken up weight training, influenced by programs like Body for Life:
   currently nearly one in five U.S. women engages in weight training on a
   regular basis.

Basic principles

   The basic principle of weight training involves a manipulation of the
   number of reps, sets, tempo, exercise types and weight moved to cause
   desired increases in strength, endurance, size or shape. A repetition
   (or "rep") is the act of lifting and lowering a weight once in a
   controlled manner. A "set" consists of a series of repetitions
   performed continuously, without rests between reps. Different exercises
   target different muscles or muscles groups. The specific combinations
   of reps, sets, exercises and weight depends upon the aims of the
   individual performing the exercise; sets with fewer reps can be
   performed with heavier weights, but have a reduced impact on endurance.

   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 an
       aerobic exercise.

   Individuals typically perform one to six sets per exercise, and one to
   three exercises per muscle group, with short breaks between each set.
   The duration of these breaks determines which energy system the body
   utilizes: for example, performing a series of exercises with little or
   no rest between them is referred to as " circuit training", and the
   body will draw most of its energy from the aerobic energy system (as
   opposed to the ATP-CP or glycogen systems, used in exercises with
   longer rests between sets).

   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. This is because
   beginners are unable to tap the full strength of the muscle; before
   they can use the full force ouput of a specific muscle, the nerves that
   innervate the muscle must be trained to fire at a high enough rate to
   cause tetanus, and contract all motor units available for the movement.

   Training to achieve different performance goals (from "Supertraining"
   by Dr. M. C. Siff)
            Variable          Strength Power  Hypertrophy Endurance
   Load (% of 1RM)            80-100   70-100 60-80       40-60
   Reps per set               1-5      1-5    8-15        25-60
   Sets per exercise          4-7      3-5    4-8         2-4
   Rest between sets (mins)   2-6      2-6    2-5         1-2
   Duration (seconds per set) 5-10     4-8    20-60       80-150
   Speed per rep (% of max)   60-100   90-100 60-90       60-80
   Training sessions per week 3-6      3-6    5-7         8-14

   Weights for each exercise should be chosen so that the desired number
   of repetitions can just be achieved. Each exercise should be performed
   according to its description; otherwise injury may result. This is
   known as "good form."

Progressive overload

   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
   (so-called " one rep max" lifts) is considered too risky for all but
   the most experienced practitioners, or novices under expert
   supervision. 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 somewhat
   smaller (sub-maximal) weights, with more repetitions, to fatigue the
   muscle—and all fibres within that muscle—as required by the progressive
   overload principle.

   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, however, a controversial topic. The
   proponents of High Intensity Training— Mike Mentzer, Arthur Jones and
   Ellington Darden—advise training to failure on every set. But other
   experts 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.

   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, and often cannot be
   safely taken to the point of momentary muscular failure.

Recovery

   There are many theories as to why weight training creates muscle
   growth. One such theory is that this training causes microtrauma to the
   muscles. Muscles grow during the rest period following a workout by
   repairs to these areas of muscle, making them stronger than before.
   Weight training programs should therefore allow the muscles time to
   repair and grow, otherwise overtraining can occur. Therefore the
   individual should exercise caution in increasing the level of exertion.
   Muscle growth is normally completed within 36 to 96 hours, depending
   upon the intensity of the workout. Novices commonly work out every
   other day, often scheduling workouts on Mondays, Wednesdays and
   Fridays. As weight trainers grow fitter and stronger, it takes more
   intense workouts to fully challenge their muscles. More advanced
   practitioners may exercise specific muscle groups only every three or
   four days.

   One solution to scheduling workouts around these needs is to split
   one's routine between several workouts, by exercising certain muscle
   groups on one day and the remainder on another. One common two-day
   split is the upper body — lower body split. Another is the front — back
   split, in which the pectorals, triceps and quadriceps are exercised on
   one day, and the lats, biceps and hamstrings on another. There are also
   three-day and four-day splits. By targeting different muscle groups,
   workouts can be scheduled more frequently than would otherwise be
   possible.

Intensity, volume, and frequency

   Three important principles of weight training, as well as exercise in
   general, are intensity, volume and frequency. Intensity refers to the
   amount of force required to achieve the activity, and in this case,
   refers to the outright weight being lifted (lifting 20kg requires more
   force or intensity than lifting 10kg, regardless of how many reps/sets
   etc are done), volume refers to how much you do in a particular
   session, and includes the number of sets, reps and exercises you do for
   each muscle, whereas frequency refers to how many sessions per week you
   do. A good analogy is the exercise of running, with the intensity being
   how fast you run, the volume being how far you run, and the frequency
   being how many times a week you run.

   These principles 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 you can’t do as many reps, and will cause more
   damage, requiring more recovery time and therefore less workouts per
   week are possible. 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
   (lack of energy) or even sickness. Therefore the high-medium-low
   formula should be used, with either intensity, volume, or frequency
   being high, one of the others being medium, and the other being low,
   following this chart as a guide:
           Type            Low         Med         High
   Intensity (% of 1RM) 10-40%     50-70%      80-100%
   Volume(per muscle)   1 exercise 2 exercises 3+ exercises
   Sets                 1 set      2-3 sets    4+ sets
   Reps                 1-6 reps   8-15 reps   20+ reps
   Session Frequency    1 p/w      2-3 p/w     4+ p/w

   Using examples from typical gym programs: doing a full body program,
   you would work each muscle as one exercise and do 2 sets of 12 reps
   (low volume), with an intensity of around 50-60% of 1RM each set
   (medium intensity), every second day (high frequency), which is typical
   of general fitness programs; doing each body part in a 3 day split, at
   50-70% of 1RM (medium intensity), with 3 exercises and 3 sets of 10
   reps (high volume), each muscle worked once a week (low frequency),
   which is typical of traditional hypertrophy programs; or 80-90% of 1RM
   (high intensity), 1-2 sets of 3-5 reps(low volume), 2 times per week
   (medium frequency), typical of muscular strength training. All of these
   programs are different examples of the high-medium-low formula,
   emphasizing one giving a different result, as the body adapts to
   specific demands.

   Most people set the volume and frequency the same each week (eg. people
   plan to come to the gym 3 times per week, and do 2 sets of 12 reps each
   workout), and steadily increase the weight (increase intensity),
   however it may be equally or more beneficial for you to keep or
   decrease the weight, and increase volume or frequency (especially true
   to achieve hypertrophy).

   Most supplements focus on improving a particular aspect, for instance
   taking creatine will give you the ability to do more sets (more volume)
   in a workout, while taking additional protein (or illegal steroids)
   will help muscle recovery, and so allow for more sessions per week
   (more frequency at the same level of intensity and volume). 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 “revved up” before a workout
   can increase the maximum weight lifted, one of the reasons why
   bodybuilders and powerlifters grunt and rev themselves and their
   training partners up, whether this is more psychological or
   physiological though is debatable, as people can often lift more weight
   than they think they can.

   Psychology definitely plays a role in training strategy. Someone who
   overtrains will feel less motivated to continue than someone who is
   undertraining, because the overtrainer begins to dislike his or her
   workout; it will seem too difficult or tiring, and this may cause a
   cycle of overtraining followed by long layoffs, which will give poor
   results. The undertrainer has no such discomfort and is likely to train
   more consistently and find a volume, frequency and intensity that is
   appropriate for their goals, even if they are not necessarily
   maximizing their potential.

Benefits

   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.

   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.

   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.

   When performed properly and at sufficient intensity, weight training
   provides an excellent stimulus to the cardiovascular system. The heart
   and lungs support the muscular system; as one taxes the muscles, the
   systems that support them are taxed. Exercise physiologists believe
   that aerobics training is a better cardiovascular stimulus due to their
   observation of maximal oxygen uptake estimates. Central catheter
   monitoring during resistance training reveals increased cardiac output,
   thus illustrating the strength training's potential for cardiovascular
   exercise.

   Other than the visible benefits, weight training can play a significant
   role in improving mental health through improved mood, self-concept and
   body satisfaction. One side-effect of general intense exercise is that
   it increases levels of dopamine, serotonin and norepinephrine, which
   can help to improve mood and counter feelings of depression.
   Individuals who exercise at least two to three times a week experience
   significantly less depression, anger, and stress than those exercise
   less frequently or not at all and regular exercisers perceive their
   health and fitness to be better than less frequent exercisers.

Common concerns

Is weight training the same as bodybuilding?

   Although weight training is similar to bodybuilding, they have quite
   different goals. Bodybuilders compete in bodybuilding competitions, so
   they train to maximize their muscular size and develop extremely low
   levels of body fat. In contrast, most weight trainers train to improve
   their strength and anaerobic endurance while not giving special
   attention to reducing body fat below normal. Weight 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.

   However, the bodybuilding community has been the source of many of
   weight training's principles, techniques, vocabulary, and customs.

Is nutrition relevant for weight trainers?

   Most people think of dieting in terms of weight loss, but weight
   trainers can also adjust their diet to improve the results from their
   workouts. Adequate protein is required for building skeletal muscle.
   Various sources advise weight trainers to consume a high protein diet
   with anywhere from 0.6 to 1.5 g of protein per pound of body weight per
   day (1.4 to 3.3 g per kg). Protein that is not 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.

   A light balanced meal consumed prior to the workout (usually one to two
   hours beforehand) ensures that adequate energy and amino acids are
   available to perform 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 (see Gainer). Some weight trainers also take
   supplements (such as creatine) to aid muscle growth. However, the
   effectiveness of some products is disputed and others are potentially
   harmful.

Do women who train with weights look "bulky"?

   Very few women are able to develop large muscles regardless of the
   program they follow; they simply lack the testosterone required to
   achieve this. 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 look slimmer.

   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 and like many male bodybuilders their results may
   be enhanced by anabolic steroids. Unless a woman dedicates her life to
   bodybuilding, she will not achieve the same results as a professional
   bodybuilder.

Are light, high-repetition exercises effective for "toning" muscles?

   Some weight trainers perform light, high-repetition exercises in an
   attempt to "tone" their muscles without increasing their size. This
   comes from misunderstanding the meaning of the word " tone." What most
   people refer to as a toned physique is one that combines reasonable
   muscular size with moderate levels of body fat. The use of the word
   "tone" in this sense is inaccurate: a more appropriate term would be
   "definition".

   Muscle tone is a physiologic term that refers to the constant,
   low-frequency contractions that occur in all muscles all the time, even
   at "rest", which prepare them for future activity. This continuous
   slight tension in torso muscles contributes to maintaining good
   posture. High-repetition exercises should increase muscle size, but
   will not improve the latter type of muscle "tone". Even performed as
   aerobic exercises they will have limited benefit, since aerobic
   exercise is most effective when it engages the whole body.

   To define muscles requires a combination of weight training to increase
   muscle size and cardiovascular training to reduce bodyfat levels.

Is weight training safe for children?

   Orthopaedic specialists used to recommend that children avoid weight
   training because the growth plates on their bones might be at risk, but
   recent studies have shown that this concern is unfounded. 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. "Growth plate injuries have not occurred in any youth strength
   training study that followed established training guidelines." The
   National Strength and Conditioning Association also confirms that "a
   properly designed and supervised resistance training programme is safe
   for children."

   Young children must be supervised around weight training equipment.
   Like adults, they may be injured if a weight is dropped, or if they
   perform an exercise incorrectly. Children may also forget to follow the
   safety guidelines, or be tempted to act irresponsibly.

Can weight training help me slim?

   Yes, but not via the low weight/high repetition approach that is
   usually used. Five minutes of crunches will expend only a small
   fraction of the energy used up in five minutes of running, because the
   abdominal muscles are so much smaller than the leg muscles. Instead,
   high weight/low rep exercises can be used to maintain (and possibly
   even 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 weight gain.

Safety

   The back must be kept straight during the squat and the deadlift.
   Enlarge
   The back must be kept straight during the squat and the deadlift.

   Weight training can be one of the safest forms of exercise, especially
   when the movements are slow, controlled, and carefully defined.
   However, as with any form of exercise, improper execution can result in
   injury. When the exercise becomes difficult towards the end of a set,
   there is a temptation to "cheat", i.e. to use poor form to recruit
   other muscle groups to assist the effort. This may shift the effort to
   weaker muscles that cannot handle the weight. For example, the squat
   and the deadlift are used to exercise the largest muscles in the
   body—the leg and buttock muscles—so they require substantial weight.
   Beginners are tempted to round their back while performing these
   exercises. This causes the weaker lower back muscles to support much of
   the weight, which can result in serious lower back injuries. To avoid
   such problems, weight training exercises must be performed correctly.
   Hence the saying: "train, don't strain".
   A lifting belt is sometimes worn to help support the lower back.
   Enlarge
   A lifting belt is sometimes worn to help support the lower back.

   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 injury.

   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. This is experienced
   as a burning sensation in the muscle, but it is perfectly harmless.
   These individuals may also experience a swelling sensation in their
   muscles from increased blood flow (the "pump"), which is also harmless.

   Beginners are advised to build up slowly to a weight training
   programme. 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
   minimise delayed onset muscle soreness. A sudden start to an intense
   programme can cause significant muscular soreness. Unexercised muscles
   contain cross-linkages that are torn during intense exercise.
   The Cross Trainer exercise machine can be used to warm up muscles in
   both the upper and lower body.
   Enlarge
   The Cross Trainer exercise machine can be used to warm up muscles in
   both the upper and lower body.

   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 joints.

   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 programme 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. In addition, the
   stabiliser muscles in the lower back and gripping muscles in the
   forearms receive less benefit from the exercises.

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 (while the length of the muscle
   decreases or increases) while in "isometric" exercises the length of
   the muscle does not change.

   Weight training is primarily an isotonic form of exercise, as the force
   produced by the muscle to push or pull weighted objects should not
   change (though in practice the force produced does decrease as muscles
   fatigue). Any object can be used for weight training, but dumbbells,
   barbells and other specialised equipment are normally used because they
   can be adjusted to specific weights and are easily gripped. Many
   exercises are not strictly isotonic because the force on the muscle
   varies as the joint moves through its range of motion. Movements can
   become easier or harder depending on the angle of muscular force
   relative to gravity - in example, a standard bicep curl becomes easier
   as the hand approaches the shoulderas more of the load is taken by the
   structure of the elbow. Certain machines such as the Nautilis involve
   special adaptations to keep resistance constant irrespective of the
   joint angle.

   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 takes place. Often this is used to increase muscular
   strength at specific joint angles, to get over 'sticking points' in an
   exercise.

   Plyometric exercises exploits 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. Plyometrics is used to develop explosive speed, and focuses
   on maximal power instead of maximal strength by compressing the force
   of muscular contraction into as short a period as possible, and may be
   used to improve the effectiveness of a boxer's punch, or to increase
   the vertical jumping ability of a basketball player.

Isolation exercises versus compound exercises

   The leg extension is an isolation exercise.
   Enlarge
   The leg extension is an isolation exercise.

   An isolation exercise is one where the movement is restricted to one
   joint and one muscle group. 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.

   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 little unnatural.
   The leg press is a compound exercise.
   Enlarge
   The leg press is a compound exercise.

   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 compound exercises.

   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 maximising
   their strength gains (including bodybuilders) would put more of an
   emphasis on isolation exercises.

Free weights versus exercise machines

   Swiss balls allow a wider range of free weight exercises to be
   performed. They are also known as exercise balls, gym balls, sports
   balls, therapy balls, medicine balls or body balls.
   Enlarge
   Swiss balls allow a wider range of free weight exercises to be
   performed. They are also known as exercise balls, gym balls, sports
   balls, therapy balls, medicine balls or body balls.

   Free weights are dumbbells and barbells. Unlike exercise machines, they
   do not constrain users to specific, fixed movements, and therefore
   require more effort from the individual's stabilizer muscles. It is
   often argued that free weight exercises are superior for precisely this
   reason. As exercise machines can go some way toward preventing 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. However, most athletes, bodybuilders and serious fitness
   enthusiasts prefer to use compound free weight exercises to gain
   functional strength.
   The weight stack from a Cable machine.
   Enlarge
   The weight stack from a Cable machine.

   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.

   There are a number of exercise machines that are commonly found in
   neighbourhood gyms. The Smith machine is a barbell that is constrained
   to move only vertically upwards and downwards. The cable machine
   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. There are also exercise-specific weight
   machines such as the leg press. A multigym includes a variety of
   exercise-specific mechanisms in one apparatus.

   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.

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. 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

   The back extension should be left to the end of the workout, because in
   other exercises the lower back muscles are used to keep the back
   straight. This is not possible if the muscles have already been
   exercised and exhausted.
   Enlarge
   The back extension should be left to the end of the workout, because in
   other exercises the lower back muscles are used to keep the back
   straight. This is not possible if the muscles have already been
   exercised and exhausted.

   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 most common
   exercises for these muscle groups are listed below. (Videos of these
   and other exercises are available at exrx.net and from the University
   of Wisconsin.) The sequence shown below is one possible way to order
   the exercises. 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 stabilising muscles in the waist should be trained last.
   Lower body

   1. Quadriceps (front of legs)

   Compound exercises for the quadriceps also involve the glutes
   (buttocks), hamstrings and calves.
     * squat (compound)
     * leg press (compound)
     * deadlift (compound)
     * lunge (compound)
     * leg extension (isolation)

   2. Hamstrings (back of legs)
     * leg curl (isolation)

   3. Calves
     * standing calf raise (isolation)
     * seated calf raise (isolation)

   Upper body

   4. Pectorals (chest)

   Compound exercises for the pectorals also involve the triceps and front
   deltoids.
     * bench press (compound)
     * pullover (compound)
     * flye (isolation)

   5. Lats (upper back)

   Compound exercises for the lats also involve the biceps and rear
   deltoids.
     * pulldown (compound)
     * bent-over row (compound)

   6. Deltoids and Trapezius (shoulders)

   Compound exercises for the shoulders also involve the arm muscles.
     * upright row (compound)
     * shoulder press (compound)
     * lateral raise (isolation)
     * shoulder shrug (isolation)

   Arms

   7. Triceps (back of arms)
     * parallel bar dip (compound)
     * pushdown (isolation)
     * triceps extension (isolation)

   8. Biceps (front of arms)
     * biceps curl (isolation)

   Waist

   9. Abdominals (belly)

   Compound exercises for the abdominals also involve the hip flexors.
     * leg raise (compound)
     * crunch (isolation)

   10. Lower back

   Some compound exercises for the legs also involve the lower back.
     * back extension (isolation)
     * good-morning (compound)
     * deadlift (compound)

Advanced techniques

   A number of techniques have been developed to make weight training
   exercises more intense, and thereby potentially increase the rate of
   progress:

Set structure

   Drop sets
          Drop sets do not end at the point of momentary muscular failure,
          but continue with progressively lighter weights.

   Pyramid sets
          In a pyramid the weight is first increased, and then decreased
          over a series of sets. A full pyramid typically includes five
          sets of approximately 12, 10, 8, 10 and 12 reps. The first two
          sets are performed with light to medium weights to warm up the
          muscles. The middle set is the work set, and uses the heaviest
          weight possible. The last two sets are drop sets, and further
          fatigue the muscle with progressively lighter weights. This
          technique provides a combination of volume and intensity, and is
          therefore popular with bodybuilders. However, the full pyramid
          may be too much for a beginner to handle, so it is only
          recommended for experienced trainers.

   Burnouts
          Burnouts combine pyramids and drop sets, working up to higher
          weights with low reps and then back down to lower weights and
          high reps.

   Diminishing set
          The diminishing set method is where a weight is chosen that can
          be lifted for 20 reps in one set, and then 70 repetitions are
          performed in as few sets as possible.

   Rest-pause (heavy singles)
          Rest-pause heavy singles are performed at or near 1RM, with ten
          to twenty seconds of rest between each lift. The lift is
          repeated six to eight times. It is generally recommended to use
          this method infrequently.

Combined sets

   Supersets
          Supersets combine two or more exercises with similar motions to
          maximize the amount of work of an individual muscle or group of
          muscles. The exercises are performed with no rest period between
          the exercises. An example would be doing bench press, which
          predominantly works the pectoralis and triceps muscles, and then
          moving to an exercise that works just the triceps such as the
          triceps extension or the pushdown.

   Push-pull supersets
          Push-pull supersets are similar to regular supersets, but
          exercises are chosen which work opposing muscle groups. This is
          especially popular when applied to arm exercises, for example by
          combining biceps curls with the triceps pushdown. Other examples
          include the shoulder press and lat pulldown combination, and the
          bench press and wide grip row combination.

   Pre-exhaustion
          Pre-exhaustion combines an isolation exercise with a compound
          exercise for the same muscle group. The isolation exercise first
          exhausts the muscle group, and then the compound exercise uses
          the muscle group's supporting muscles to push it further than
          would otherwise be possible. For example, the triceps muscles
          normally help the pectorals perform their function. But in the
          "bench press" the weaker triceps often fails first, which limits
          the impact on the pectorals. By preceding the bench press with
          the pec flye, the pectorals can be pre-exhausted so that both
          muscles fail at the same time, and both benefit equally from the
          exercise.

   Breakdowns
          Breakdowns were developed by Fred Hatfield and Mike Quinn to
          work the different types of muscle fibers for maximum
          stimulation. Three different exercises that work the same muscle
          group are selected, and used for a superset. The first exercise
          uses a heavy weight (~85% of 1 rep max) for around five reps,
          the second a medium weight (~70% of 1 rep max) for around twelve
          reps, and finally the third exercise is performed with a light
          weight (~50% of 1 rep max) for twenty to thirty reps, or even
          lighter (~40% of 1 rep max) for forty or more reps. ( Going to
          failure is discouraged.) The entire superset is performed three
          times.

Beyond failure

   Forced reps
          Forced reps occur after momentary muscular failure. An assistant
          provides just enough help to get the weight trainer past the
          sticking point of the exercise, and allow further repetitions to
          be completed. Weight trainers often do this when they are
          spotting their exercise partner. With some exercises forced reps
          can be done without a training partner. For example, with
          one-arm biceps curls the other arm can be used to assist the arm
          that is being trained.

   Cheat reps
          Cheating is a deliberate compromise of form in order to achieve
          further reps. Cheating has the advantage that it can be done
          without a training partner, unlike forced reps.

   Rest-pause (post-failure)
          After a normal set of 6-8 reps (to failure), the weight is
          re-racked and the trainer takes 10-15 deep breaths, and then
          performs one more repetition. This process can be repeat for two
          further repetitions. The twenty-rep squat is another, similar
          approach, in that it follows a 12-15 rep set of squats with
          individual rest-pause reps, up to a total of 20 reps.

   Negative reps
          Negatives are performed with much heavier weights. Assistants
          lift the weight, and then the weight trainer attempts to resist
          its downward progress. Alternatively, an individual can use an
          exercise machine for negatives by lifting the weight with both
          arms or legs, and then lowering it with only one. Or they can
          simply lower weights more slowly than they lift them: for
          example, by taking two seconds to lift each weight and four
          seconds to lower it.

   Partial reps
          Partial reps, as the name implies, involves movement through
          only part of the normal path of an exercise. Partial reps can be
          performed with heavier weights. Usually, only the easiest part
          of the repetition is attempted.

   Burns
          Burns involve mixing partial reps into a set of full range reps
          in order to increase intensity. The partials can be performed at
          any part of the exercise movement, depending on what works best
          for the particular exercise. Also, the partials can either be
          added after the end of a set or in some alternating fashion with
          the full range reps. For example, after performing a set of
          biceps curls to failure, an individual would cheat the bar back
          to the most contracted position, and then perform several
          partial reps.

   X-reps
          X-reps are a variation of burns, but X-reps always occur after
          momentary muscular failure. After the last full repetition, an
          isometric contraction at the point of maximum force is combined
          with a series of small pulsing movements to further stress the
          muscles. However, in a 1997 article Steve Holman states that
          "X-Rep training is simply placing a muscle in its completely
          contracted position, or close to it, against resistance and
          holding it there until the muscle can no longer contract. Once
          you achieve fatigue overload, you slowly lower the weight
          through the eccentric range of motion, and the set is complete."

Other techniques

   Super slow
          Super slow repetitions are performed with lighter weights. The
          lifting and lowering phases of each repetition take 10 seconds
          or more.

   Timed rests
          By strictly controlling the rest periods between reps and sets a
          trainer can reduce their level of blood oxygenation, which helps
          to increase the stress on the muscles.

   Using a wrist strap.
   Enlarge
   Using a wrist strap.

   Wrist straps
          Wrist straps (lifting straps) are sometimes used to assist in
          gripping very heavy weights. They are particularly useful for
          the deadlift. Some lifters, however, avoid using wrist straps in
          order to develop their grip strength. Wrist straps can allow a
          lifter initially to use more weight than they might be able to
          handle safely for an entire set. They can also place potentially
          harmful stress on the bones of the wrist. Instead, wrist curls
          and reverse wrist curls can be done to improve grip strength.

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