Strength - is the capacity of the whole body or of any of its parts to exert force. There are two types of strength - Dynamic & static strength Following mention methods are used to improve strength.
1. Isometric Exercise : The word isometric is comprised of 2 words “iso “same” and “metric “length”. Means when we do these exercises work done cannot be observed. These exercises require less time and equipments and can be carried out anywhere. These exercises are useful for maintaining strength in case of injury.
Eg. Archery, weight lifting, gymnastic are the examples of isometric movements.

Work done = Force X Distance moved
but distance moved is 0, therefore work done is zero.
2. Isotonic Exercises :- “Iso” Means ‘same’ and ‘tonic’ means ‘tension’. In these types of exercise when we do movements it can be observed directly. The lenghenig and shorting of muscles can be seen and called eccentric Contraction and concentric contraction accordingly. Ex. When we throw a ball, jump. run, weight training, these type of contraction occurs. These Type of exercise is widely seen in games & sports. We can do these exercise with equipment or without equipment. These increase and length of th muscles and are good for conditioning in sports.

3. Iso-Kinetic Exercises -- “Iso” - ‘Same’ “and’ kinetic - motion’. These exercises were introduced by j.j. perrine in 1968. These exercise are done by specially design machine and are combination of isotonic and Iso-metric exercises. These exercises develop strength of muscles. These type of movements are usually not applied in games and sports except water sports, skating, climbing, running etc.
