Isoinertial denotes a type of resistance used in

exercise Exercise is a body activity that enhances or maintains physical fitness and overall health and wellness. It is performed for various reasons, to aid growth and improve strength, develop muscles and the cardiovascular system, hone athletic s ...

training which maintains a constant

inertia Inertia is the idea that an object will continue its current motion until some force causes its speed or direction to change. The term is properly understood as shorthand for "the principle of inertia" as described by Newton in his first law o ...

throughout the

range of motion Range of motion (or ROM), is the linear or angular distance that a moving object may normally travel while properly attached to another. It is also called range of travel (or ROT), particularly when talking about mechanical devices and in mechanic ...

, facilitating a constant resistance and maximal muscle force in every angle. The term ''isoinertial'' derives from the words iso (same) and inertial (resistance), which in one terminology describes the primary concept of the isoinertial system, or expressing the same inertia in both the

concentric In geometry, two or more objects are said to be concentric, coaxal, or coaxial when they share the same center or axis. Circles, regular polygons and regular polyhedra, and spheres may be concentric to one another (sharing the same center ...

and the

eccentric Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off- center, in geometry * Eccentricity (graph theory) of a ...

phases of

muscle contraction 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 ...

The Origins

Since the late eighties, during long-duration space travel, was placed as a problem as the ability to maintain power the muscles of

astronauts An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a human spaceflight program to serve as a commander or crew member aboard a spacecraft. Although generally r ...

engaged in missions, given that the absence of

gravity In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the str ...

led to an environment in which they experienced

atrophy Atrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include mutations (which can destroy the gene to build up the organ), poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply ...

of the

musculoskeletal system The human musculoskeletal system (also known as the human locomotor system, and previously the activity system) is an organ system that gives humans the ability to move using their muscular and skeletal systems. The musculoskeletal system prov ...

, no longer called to support the load of the body weight, as well as a reduction in bone mineral density. Studies and research carried out about a solution that led to the strengthening of

muscles Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...

of astronauts and subsequently, over the years, has become a method of muscle training very useful for preservation, prevention and rehabilitation. In practice it was created a

flywheel training Flywheel training is a type of strength training where the resistance required for muscle activation is generated by the inertia of a flywheel instead of gravity from weights as in traditional weight training. In contrast to weight training, flywh ...

system for

resistance training Strength training or resistance training involves the performance of physical exercises that are designed to improve strength and endurance. It is often associated with the lifting of weights. It can also incorporate a variety of training te ...

with a belt and a

flywheel A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy; a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, assu ...

that, driven by the belt, controlling a process which generated movement regardless of the strength of gravity.

The Isoinertial Method

The isoinertial's muscle activity follows the muscular action of the sporting gesture or rather what the body or parts of it are in duty to perform in sports, according to which, in strength and speed variable, an

inertial In classical physics and special relativity, an inertial frame of reference (also called inertial reference frame, inertial frame, inertial space, or Galilean reference frame) is a frame of reference that is not undergoing any acceleration. ...

load (such as a ball), a limb or the body itself (such as when accelerating or changing direction) the athlete is forced to respond at the level coordinative motor and neuromuscular very quickly to situations and motor gestures sudden and not predetermined.

The Benefits

The great utility of the isoinertial method and at the same time what makes it different from the normal isotonic muscle movement lies in the fact that the action isotonic developed in conventional exercises (strength machines and free weights), the resistance is constant throughout the whole of movement in both the concentric phase in which the eccentric, which is equivalent to the set load. In the isoinertial method the resistance is adapted in every moment and is proportional to the force developed in the sense that the greater the force expressed by the subject in the concentric phase, the greater will be the acceleration with which the flywheel reacts.

External links

* * *{{cite web , url=http://exxentric.com/physical-principles/ , title=Physical Principles: "Isoinertial" , access-date=2017-12-06 , publisher=Exxentric Human spaceflight Physical exercise