Isometric exercise device

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An isometric exercise tool is a device used to exercise most body parts including the wrist and is often used as part of physical therapy or in order to build muscle strength in a low impact manner. Devices can range in size from large bulky machines used by physicians to small hand-held devices that can be used by an individual. Isometric devices have been used for centuries. The first devices did not display the users' output; nowadays there are devices that can digitally output the users force. Before that some devices used an analog format.

Contents

How it works

Isometric exercise tools perform exercises or strength test using static contraction of a muscle without any visible movement in the angle of the joint. This is reflected in the name; the term "isometric" combines the prefix "iso" (same) with "metric" (distance), meaning that in these exercises the length of the muscle does not change, [1] as compared to isotonic contractions ("tonos" means "tension" in Greek) in which the contraction strength does not change but the joint angle does. New isometric exercise tools often used force gauges and a micro processor and then output the force onto an LCD screen or store the information later to be downloaded onto a computer.

Medical uses

Isometric exercises can also be used at the bedside to differentiate various heart murmurs; the murmur of mitral regurgitation gets louder [2] as compared to the quieter murmur of aortic stenosis. [3]

Comparison with dynamic exercises

Isometric exercises have some differences in training effect as compared to dynamic exercises. While isometric training increases strength at the specific joint angles of the exercises performed and additional joint angles to a lesser extent, dynamic exercises increase strength throughout the full range of motion. [4] Generally speaking however, people who train isometrically don't train through a full range of motion as the strength gained at the training joint angle is where they require it. While dynamic exercises are slightly better than isometric exercises at enhancing the twitch force of a muscle, isometrics are significantly better than dynamic exercises at increasing maximal strength at the joint angle. [5] Flexibility may be increased when isometrics are performed at joint range of motion extremes. These isometric contractions recruit muscle fibers that are often neglected in some dynamic exercises. For example, gymnasts are extremely strong at great ranges of motion through the practice of isometric holds.

See also

Related Research Articles

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Weight training is a common type of strength training for developing the strength and size of skeletal muscles. It utilizes the force of gravity in the form of weighted bars, dumbbells or weight stacks in order to oppose the force generated by muscle through concentric or eccentric contraction. Weight training uses a variety of specialized equipment to target specific muscle groups and types of movement.

Rotator cuff Group of muscles

In anatomy, the rotator cuff is a group of muscles and their tendons that act to stabilize the shoulder and allow for its extensive range of motion. Of the seven scapulohumeral muscles, four make up the rotator cuff. The four muscles are the supraspinatus muscle, the infraspinatus muscle, teres minor muscle, and the subscapularis muscle.

Skeletal muscle One of three major muscle types

Skeletal muscles, commonly called muscles, are organs of the vertebrate muscular system that are mostly attached by tendons to bones of the skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle tissue, and are often known as muscle fibers. The muscle tissue of a skeletal muscle is striated – having a striped appearance due to the arrangement of the sarcomeres.

Physical strength

Physical strength is the measure of a human's exertion of force on physical objects. Increasing physical strength is the goal of strength training.

Delayed onset muscle soreness (DOMS) is the pain and stiffness felt in muscles several hours to days after unaccustomed or strenuous exercise.

Muscle fatigue is the decline in ability of muscles to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction. There are two main causes of muscle fatigue: the limitations of a nerve’s ability to generate a sustained signal ; and the reduced ability of the muscle fiber to contract.

Stretching Form of physical exercise where a muscle is stretched to improve it

Stretching is a form of physical exercise in which a specific muscle or tendon is deliberately flexed or stretched in order to improve the muscle's felt elasticity and achieve comfortable muscle tone. The result is a feeling of increased muscle control, flexibility, and range of motion. Stretching is also used therapeutically to alleviate cramps and to improve function in daily activities by increasing range of motion.

Muscle contraction Activation of tension-generating sites in muscle

Muscle contraction is the activation of tension-generating sites within muscle cells. In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding a heavy book or a dumbbell at the same position. The termination of muscle contraction is followed by muscle relaxation, which is a return of the muscle fibers to their low tension-generating state.

Strength training

Strength training or resistance training involves the performance of physical exercises which are designed to improve strength and endurance. It is often associated with the use of weights. It can also incorporate a variety of training techniques such as calisthenics, isometrics, and plyometrics.

Squat (exercise) Workout that targets the legs

A squat is a strength exercise in which the trainee lowers their hips from a standing position and then stands back up. During the descent of a squat, the hip and knee joints flex while the ankle joint dorsiflexes; conversely the hip and knee joints extend and the ankle joint plantarflexes when standing up.

Isometric exercise Static contraction exercises

An isometric exercise is a form of exercise involving the static contraction of a muscle without any visible movement in the angle of the joint. The term "isometric" combines the Greek words isos (equal) and -metria (measuring), meaning that in these exercises the length of the muscle and the angle of the joint do not change, though contraction strength may be varied. This is in contrast to isotonic contractions, in which the contraction strength does not change, though the muscle length and joint angle do.

Plyometrics Maximum intensity explosive exercises

Plyometrics, also known as jump training or plyos, are exercises in which muscles exert maximum force in short intervals of time, with the goal of increasing power (speed-strength). This training focuses on learning to move from a muscle extension to a contraction in a rapid or "explosive" manner, such as in specialized repeated jumping. Plyometrics are primarily used by athletes, especially martial artists, sprinters, arm wrestlers and high jumpers, to improve performance, and are used in the fitness field to a much lesser degree.

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Vertical jump Jump vertically in the air

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Electrical muscle stimulation Use of electricity to involuntarily contract muscle

Electrical muscle stimulation (EMS), also known as neuromuscular electrical stimulation (NMES) or electromyostimulation, is the elicitation of muscle contraction using electric impulses. EMS has received an increasing amount of attention in the last few years for many reasons: it can be utilized as a strength training tool for healthy subjects and athletes; it could be used as a rehabilitation and preventive tool for people who are partially or totally immobilized; it could be utilized as a testing tool for evaluating the neural and/or muscular function in vivo; it could be used as a post-exercise recovery tool for athletes. The impulses are generated by a device and are delivered through electrodes on the skin near to the muscles being stimulated. The electrodes are generally pads that adhere to the skin. The impulses mimic the action potential that comes from the central nervous system, causing the muscles to contract. The use of EMS has been cited by sports scientists as a complementary technique for sports training, and published research is available on the results obtained. In the United States, EMS devices are regulated by the U.S. Food and Drug Administration (FDA).

Bullworker is a product and fitness company that specializes in isometric exercise. The original portable home fitness device was invented by Gert F. Kölbel in 1962.

An eccentric contraction is the motion of an active muscle while it is lengthening under load. Eccentric training is repetitively doing eccentric muscle contractions. For example, in a biceps curl the action of lowering the dumbbell back down from the lift is the eccentric phase of that exercise — as long as the dumbbell is lowered slowly rather than letting it drop.

Normal aging movement control in humans is about the changes in the muscles, motor neurons, nerves, sensory functions, gait, fatigue, visual and manual responses, in men and women as they get older but who do not have neurological, muscular or neuromuscular disorder. With aging, neuromuscular movements are impaired, though with training or practice, some aspects may be prevented.

Fascia training describes sports activities and movement exercises that attempt to improve the functional properties of the muscular connective tissues in the human body, such as tendons, ligaments, joint capsules and muscular envelopes. Also called fascia, these tissues take part in a body-wide tensional force transmission network and are responsive to training stimulation.

Power training Common type of speed and strength training

Power training typically involves exercises which apply the maximum amount of force as fast as possible; on the basis that strength + speed = power. Jumping with weights or throwing weights are two examples of power training exercises. Regular weight training exercises such as the clean and jerk and power clean may also be considered as being power training exercises due to the explosive speed required to complete the lifts. Power training may also involve contrasting exercises such as heavy lifts and plyometrics, known as complex training, in an attempt to combine the maximal lifting exertions with dynamic movements. This combination of a high strength exercise with a high speed exercise may lead to an increased ability to apply power. Power training frequently specifically utilises two physiological processes which increase in conjunction with one another during exercise. These are deep breathing, which results in increased intra-abdominal pressure; and post-activation potentation, which is the enhanced activation of the nervous system and increased muscle fibre recruitment. Power training programmes may be shaped to increase the trainee's ability to apply power in general, to meet sports specific criteria, or both.

References

  1. Article on static strength training
  2. Ching, W. "Evaluation of Cardiac Murmurs in the Clinic Setting" (PDF). University of Chicago. Archived from the original (PDF) on 2008-12-17. Retrieved 2008-01-10.
  3. Cassidy J, Aronow WS, Prakash R (1975). "The effect of isometric exercise on the systolic murmur of patients with idiopathic hypertrophic subaortic stenosis". Chest. 67 (4): 395–7. doi:10.1378/chest.67.4.395. PMID   1168115.
  4. Lindh M (1979). "Increase of muscle strength from isometric quadriceps exercises at different knee angles". Scand J Rehabil Med. 11 (1): 33–6. PMID   419396.
  5. Duchateau J, Hainaut K (1984). "Isometric or dynamic training: differential effects on mechanical properties of a human muscle". Journal of Applied Physiology. 56 (2): 296–301. doi:10.1152/jappl.1984.56.2.296. PMID   6706740.