Nowadays, World Rugby specifies the shape, dimensions and weight of the modern rugby ball, which must be elliptical, made of four panels and weigh between 410 and 460 grams. Dimensions-wise, the ball must be between 280 and 300mm in length, with an end-to-end circumference of between 740 and 770mm and a circumference between 580 and 620mm around the middle, or width, of the ball.
However, in the early pioneering days of rugby, during the nineteenth century, rugby balls were typically made from raw pigs’ bladders inflated, by mouth, with a clay pipe stem, covered in leather and stitched together by hand. Consequently, the ball took on, more or less, the shape of the bladder; larger and more spherical than the modern rugby ball. In 1892, the governing body of rugby union in England, the Rugby Football Union, decreed that the rugby ball should be oval. Subsequently, the original plum-shaped rugby became flatter and more elongated, with more tapered ends, making it more suitable for handling and kicking during a rugby match.
Retired American sprinter Michael Johnson made history when, in 1996, he became the first male athlete to win both the 200-metre and 400-metre events at the same Olympics. Indeed, in the 200-metre final in Atlanta, Johnson produced a time of 19.32 seconds, improving on his own world record time of 19.66 seconds, which he had set in the US Olympic Trials just over a month earlier, by 0.34 seconds; his record stood for twelve years, until broken by Usain Bolt in 2008. Furthermore, in 1999, despite a season blighted by injury, Johnson won the 400-metre final at the World Athletics Championship in Seville, Spain in a new world record time of 43.18 seconds; that record would stand even longer, until broken by Wayde van Niekerk in 2016.
Johnson was recognisable not only by his specially commissioned, golden-coloured Nike track spikes, but by his unorthodox, upright running style, which attracted widespread criticism in the early days of his career. Conventional wisdom dictates that a high knee lift, which facilitates a powerful downstroke phase, is necessary for maximum speed over 200 or 400 metres. However, despite standing 6 feet tall, Johnson has a atypical vertical body type for a sprinter, with a long torso and short legs. His solution to transferring force into the track or, in other words, to generating speed, was to take short, choppy strides, but increase his stride frequency, or leg turnover. His statuesque, straight-up running style may not have been visually appealing to sprinting ‘purists’, but it was certainly effective. His ground contact time was measured at around 0.006 seconds and scientific studies of his style revealed that it was, in fact, much more efficient than traditional sprinting techniques.