Did you know that hitting a powerful drive on the golf course takes more than just strength and coordination, it also require some physics! This year, we have decided to do something very different and delve deep into the science behind one of the most popular sporting games in the world. We caught up with our keynote speaker, Ian Kenny, to find out more in advance.
Ian, we are delighted to be hosting something very unique for this year’s Midlands Science Festival and we would like to welcome you as one of our key speakers for our public talk which is entitled the Science of Golf. Can you tell us about your own background?
I am originally from Co Antrim. Golf has not always been my main interest, having enjoyed competing in long jump internationally for Northern Ireland and Ireland in my teens and twenties. I studied for a BSc in Sport Sciences at Ulster University and in my final year really concentrated on biomechanics, which is the study of the application of physics to human movement, forces and movement patterns. Good grades and a continued interest in biomechanics then led me to receive a joint PhD scholarship from Ulster University and the R&A St Andrews, to study the biomechanical and performance effects of long drivers. The golf equipment rule limiting drivers to 48” (1.22 m) length was part of that work.
I am now a senior lecturer in biomechanics at the University of Limerick, having moved there in 2007. I teach functional anatomy and biomechanics to students on several UL courses including the BSc Sport and Exercise Sciences, and the BSc in Physical Education. My research covers many aspects of biomechanics within sports performance and sports medicine and I supervise the work of PhD students studying running mechanics, golf movement, and Rugby injuries.
Would you say there is science involved in day-to-day golf?
My view is that the science involved should help the game, protect the rules and should make the game enjoyable for all playing levels and ages. Professional golfers on tour account for less than 0.1% of the estimated 32 million golfers worldwide, so the arguments about the demise of the game in terms of long drive shots due to equipment advances really do not have much effect on the playing masses. The top 30 golfers on the PGA tour on average only hit the fairway from a drive two out of every three shots!
Science is involved in work by manufacturers of clubs and balls concerning materials, feel, acoustics, and shot measurement, it is involved in the biomechanics of coaching, nutrition and physiological effects, psychological preparation, and also conditioning and training principles.
A good example of a really useful scientific input is club fitting. After a golfer learns the swing basics and plays the game for a while, club fitting by a club coach or pro will assess swing characteristics such as swing speed and ball rotation speed, and match a club type to your own swing and ball speed. The coach will normally use Doppler radar technology within a launch monitor to assess those characteristics. A slower swing should be matched with a more flexible club shaft, giving a little more club head speed to the shot while maintaining control. The aim here is to help golfers enjoy the game by hitting well and consistently, rather than play with clubs not suited to them.
A golf ball has hundreds of small impressions, or dimples, on its surface. What is the reason for this? Does it affect the ball’s flight?
Put simply, dimples makes them fly further, usually 200 yards (183 m) further for an elite golfer.
The flow of air round an object can be described as either laminar or turbulent flow: smooth or choppy air flow. Laminar flow past a round shape will result in the separation of the flow behind the ball – the flow of the air will stream outwards behind the object, like the way that ripples spread apart behind a duck or boat on the water. Laminar flow is perfect for sports like cycling or speed skating where fast movement and little drag is important.
Flow of air around a rough shape, like a spinning dimpled golf ball, will be turbulent and although this can generate more drag, the air flow sticks to the surface and separates much less easily. This means that dimpled balls overall cause the least disruption of the air and travel much more efficiently and further.
In golf it’s all about the direction and distance the ball flies. Golf balls are designed to react differently to swing speed, typical spin rates and ground conditions. A drive shot will have a relatively low backspin rate giving the ball more flight distance but an iron shot will produce much higher ball spin and aid control of the ball when it lands on the green. Balls are made from a variety of materials and in a range of methods, to provide more desirable flight characteristics, to meet the needs of both professionals and amateurs.
All golf shots have backspin which is when the ball rotates backwards along a horizontal axis in a direction opposite to its flight path. Backspin allows the air around a dimpled ball to travel with it in a direction that creates a pocket of low pressure at the top and high pressure at the bottom. It is easier for an object to move from an area of high to low pressure therefore the ball will lift and there is flight, until the spin degenerates sufficiently that the weight of the ball overcomes lift and brings it back to earth.
Why do you think national events like Science Week are so important?
I believe it is really important for people to avoid what I call the ‘black box scenario’. This is where people take no notice of the science and technology involved in everything around them, from the electronics coding needed in the software that sends e-mails, to the compound design of car tyre rubber, to the material used in a golf driver! Seamless integration of science and technology into our lives is welcome, but a little understanding of what goes into product development for either performance or health and safety reasons is a good thing for everyone, and especially for the school-age generation it will aid inquisition and interest for future product, health or computing developments.