Use this section as a reference tool to maximize your vocabulary . We realize that some of you are more advanced bodybuilding enthusiasts have already grasped the meaning of these terms but for others, an explanation of what they mean will take your knowledge base to higher level.

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IFBB - International Federation of Bodybuilders, founded in 1946 - The IFBB controls both the amateur and professional divisions, and counts among its sport disciplines men's, women's, juniors, masters and mixed-pairs bodybuilding; women's fitness and body fitness; and men's fitness.

Intensity - The relative degree of effort that you put into each set of every exercise in a bodybuilding workout. The more intensity you place on a working muscle, the more quickly it will increase in hypertrophy.

Isokinetic Exercise - Form of active resistive exercise in which the speed of limb movement is controlled by a pre-set limiting machine, such as Cybex or Biodex.

Isometric Exercise - Isometric exercise is a form of physical exercise in which the muscles flex and hold a stationary position. No movement of a load or joint angle takes place, and the exercises require little in the way of equipment. An example of an isometric exercise is placing the palms of the hands against each other and pushing. Isometric exercises are primarily used in physiotherapy and injury rehabilitation because the intensity can be rapidly and precisely adjusted, which makes them very safe.

Isolation Exercise - Isolation movement stresses a single muscle group (or sometimes just part of a single muscle) in relative isolation from the remainder of the body.

Isotonic Exercise - exercise in which opposing muscles contract and there is controlled movement (tension is constant while the lengths of the muscles change). The classic isotonic exercise is lifting free weights.