A fast bowler with a lower back injury
Since the mid-1980s, there has been much research aimed at identifying the causes of lower back injuries in bowlers. Typically, there are three bowling actions for fast bowlers: the front-on technique with hips and shoulders remaining parallel to the crease for much of the action; the side-on technique whereby the action starts with the hips and shoulders pointing down the pitch; and the mixed action whereby the bowler usually counter-rotates the shoulders towards a side-on position early in the action. This mixed action can place additional rotational stress on the lower back, and as such has been identified by a number of scientific studies as the action most likely to result in injury (for a review of these studies, see Bartlett et al, 1996, and Finch et al, 1999). Typical injuries include spondylolysis (a stress fracture of the lumbar vertebrae), disc degeneration, and muscle and other soft-tissue damage. Fast bowlers are also at risk because of the repetition of their actions, repeatedly placing high stresses on the joints of their lower limbs and lower back.
Despite this recently acquired knowledge, many bowlers participating in the game at all levels are still regularly becoming injured. Typically, the injured bowler will see a physiotherapist who will treat the injury until the player is fit again. However, this is often no more than a temporary solution and coaches need to discover more long-term answers to ensure that their players are able to perform at their best for as long as possible. Modification of a potentially injurious bowling action is one longer-term solution that has already had some success in preventing the recurrence of injury, especially in Australia (eg the left-arm pace bowler Bruce Reid in the late 1980s). This case study similarly attempted to modify the action of a promising young injured bowler, using an innovative new video system.
Seeing is feeling
The bowler was recommended to the Sports Science Consultancy Unit at Chelsea School, University of Brighton, by his physiotherapist. He was treated for lower back pain that was suspected to be spondylolysis. As he was still relatively young, staff at the Consultancy Unit decided to attempt to modify his action with the help of Sussex County Cricket Club's coach, Peter Moores, and the Quintic Video Analysis System. This system involves a digital video camera linked to a laptop computer that allows almost instantaneous playback on the laptop screen. Images can be viewed in real time, slow motion or frame-by-frame, and, as shown in Figure 1, sequences filmed on two separate occasions can be viewed side-by-side on the same screen.
The Quintic System also allows joint angles to be measured and compared if required. Thus, by viewing each delivery immediately after it was performed, the bowler was able to experience feelings associated with his 'injurious' technique and, later, those associated with the 'less injurious' technique as it was modified. In addition, both coach and bowler were able to monitor and measure the changes that occurred in the action throughout the coaching period.
What needed changing?
Aspects of the bowler's action that were identified by the coach as in need of modification were: limited drive of the right leg; poor foot placement; excessive flexion of the trunk towards the left (off-side); and extensive rotation of the trunk and poor use of arms in the follow-through. The excessive lateral flexion and rotation of the trunk, as shown in the right side of Figures 1 and 2 respectively, were thought to be most related to the lower back injury suffered by the bowler. The coach also encouraged the bowler to 'stand tall' and bowl through the crease in a straight line rather than rotating around the front left after release, as shown in the right side of Figure 2.
Coaching sessions took place at least once a month for a period of four months. The Quintic System was used on these occasions and on a number of follow-up sessions to allow the bowler to monitor the changes that had occurred in his action. It is important to mention that the changes were introduced gradually and systematically. Interestingly, the bowler was not very adept at identifying the feelings associated with either 'good' or 'bad' techniques early on in the coaching programme. He gradually became more aware of alterations in his action, and near the end of the programme he became very good at noticing slight alterations in technique.
Comparison of the left image with the right image of Figures 1 and 2 show that the bowler's technique was modified with a great deal of success. The left side of Figure 1 shows that the bowler's spine was more upright at the point of ball release, which should reduce stress in the left lower back, where the pain was felt. The bowler's body no longer rotated excessively around the planted front leg, and the right-leg drive was more powerful and directed down the pitch (see Figure 2).
What happened next
During the four-month coaching programme the bowler did not bowl at full speed in order to help him concentrate on the changes, nor did he bowl in any matches. He also attended a Polartis course aimed at improving core stability. This was also deemed important since he tended to allow his body to fall to the left during delivery, which arguably was contributing to the cause of the injury. With better core stability he was better able to support his action and remain more upright.
A follow-up analysis session was carried out after a period of three months, during which no coaching or analysis sessions were offered, and the bowler was therefore left alone to continue practising. Encouragingly, the Quintic System was able to show that he had retained the new modified action and had not reverted to the old one. More encouragingly, the bowler no longer complained of low-back pain. Feedback from the bowler revealed that expert coaching using the Quintic System had been the key to enable him to modify his action.
This case study has been a great success and goes some way to demonstrating how applied sports science can be used in cricket and the modification of bowling techniques to reduce the risk of injury. Similar studies are now being carried out using the Quintic System on batting technique, tennis serving, and swimming strokes.
If you want further information about this study, contact Rob Harley (Senior Lecturer in Physiology and Head of Sports Science Consultancy at the University of Brighton)
on 01273 643758;
Bartlett, R.M., Stockhill, N.P., Elliott, B.C., and Burnett, A.F. (1996). 'The biomechanics of fast bowling in men's cricket: a review.' Journal of Sport Science, 14, pp 403-424
Finch, C.F., Elliott, B.C., McGrath, A.C. (1999). 'Measures to prevent cricket injuries: an overview.' Sports Medicine, 28, pp 263-272