The fiberglass pole used in the pole vault since the late 1960s is the chief reason why the world record in this event has been improved by a greater percentage margin than any other Olympic sport since 1968. The poles used by vaulters progressed from hardwood, to bamboo, to aluminum, and ultimately to fiberglass within a period of approximately 40 years. Since 1968, all Olympic and world champions have used a pole manufactured from either fiberglass or a composite product that has included fiberglass. Herbert Jenks was a pioneer in the development of this record setting technology.
The physics of pole vault create an event where each component of the attempted jump builds directly on the previous step. The fast approach down the runway towards the bar leads to the aggressive plant of the pole by the vaulter. The athlete uses the speed and power of the approach and plant to take off and extend into the air; the vaulter's extension over the bar requires the pole to be in a vertical position as the bar is cleared.
The greater flexibility of the fiberglass pole as opposed to any other materials permits the athlete to achieve a greater bend in the pole when it is planted. This quality of fiberglass means that the athlete can position their hands higher on the pole, further from the point of the pole when it is planted. The further along the pole the athlete can grip the pole, the generally higher they will be able to jump.
Herbert Jenks was a fiberglass engineer with the Browning Arms company in the late 1950s, where he was engaged in the manufacture of fiberglass tubes used in archery. Jenks began to design and build fiberglass vaulting poles in 1960; he is the first person in North America to patent a fiberglass vaulting pole. Jenks worked with a number of different pole designs until 1968, most notably the Browning Sky Pole and the Black Cata-Pole, designs used by many leading vaulters of the era; he created the first pole with a small tapered grip area, to achieve a better position for the vaulter's hands. Jenks also designed poles that were variably weighted, with the weight distributed along the pole to suit the individual preferences of the vaulter. Jenks patented a number of his later pole designs as well as training others in the art of manufacturing a vaulting pole. In 1976 Jenks was issued a further patent with respect to the manufacturing process of a then state of the art pole produced by AMF-Voit, an American manufacturing concern.