There are several forms of exercises,
but the more widely known are Isometric, Isotonic, Isokinetic, Aerobic, Anaerobic, Yogic and
Callisthenic. The brief descriptions are given below:
Isometric: Isometric exercises are those in which the body is pitted against an immovable resistance such as in dynamic tension, the Bullworker etc. It is a system of exercises in which opposing muscles are so contracted that there is little shortening but great increase in tone (condition of tension and elasticity) of muscle fibres involved.
Isotonic: Isotonic exercises are those in which the body is pitted against a moveable resistance such as weight training.
Isokinetic: Isokinetic exercises are those in which the muscles are pitted against a constant moveable resistance, such as found in modern gym equipment.
Aerobic: Aerobic exercises are those exercises during which the heart-lung and respiratory systems are activated resulting in infusing the body with oxygenated blood. This form or system of exercise is highly beneficial in increasing the stamina of the body as it increases the efficiency of the heart, lungs and the circulation system.
Anaerobic: Anaerobic activities are those activities in which the body has to function without oxygenated blood such as sprinting and other explosive sports like weightlifting, powerlifting etc.
Yogic: Yogic exercises and yoga asanas (postures) are free hand exercises and their benefit is derived from stretching the body and thus giving it flexibility and suppleness. They also help in attaining bodily or mental control and well-being.
Callisthenic: Callisthenics are systematic rhythmic bodily exercises, performed usually without apparatus and are thus similar to yoga. They are frequently employed in the warm-up or limber-down that precedes or follows any sports activity.
The physical fitness of the body comprises four basic factors viz. strength, speed, stamina and suppleness (flexibility). Each of these exercise systems explained above concentrate on only one basic factor of physical fitness whereas the most ideal system of total fitness should co-ordinate all the four factors.