The Evolution of Bars

 Uneven bars has changed a lot over the years.  It originally consisted of men's parallel bars set to different heights.  The bars were very lose together and gymnasts could go from the high bar to the low bar with little difficulty. 

In the 1950's routines usually consisted of simple circles, kips, balance elements, and holds like you might see on beam.  Release moves even began to come into play but they were almost entirely limited to transitions between the low and high bars.

In the late 1960's to the early 70's, companies began manufacturing uneven bars as a separate specific apparatus.  The design was changed slightly to allow the bars to be adjustable, with tension cables that held the bars to the floor.  As a result of this change, caches could set the bars further apart.  Additionally, the circumference of the bars themselves decreased, allowing gymnasts to grasp and swing from them with greater ease.

                                                       Emilia Eberle on bars in 1979
By the mid 80's, routines had become so based on swing and release moves that the bars were moved even farther apart.  The distance between the bars increased even more as gymnasts developed difficult transition elements that required space. 

                                          
                                                   Me at level 9 Regionals April, 2013