Bowling Arm Research Articles

Optimal initial position and technique for the front foot contact phase of cricket fast bowling: Commonalities between individual-specific simulations of elite bowlers

Group-based and individual-based studies in cricket fast bowling have identified common technique characteristics associated with ball release speed. The applicability of these findings to individual bowlers is often questioned, however, due to research approach limitations. This study aims to identify whether the optimal initial body position at front foot contact and subsequent technique to maximise ball release speed exhibit common characteristics for elite male cricket fast bowlers using individual-specific computer optimisations. A planar 16-segment whole-body torque-driven simulation model of the front foot contact phase of fast bowling was customised, evaluated, and the initial body position and subsequent movement pattern optimised, for ten elite male fast bowlers. The optimised techniques significantly increased ball release speed by 4.8 ± 1.3 ms−1 (13.5 ± 4.1%) and ranged between 37.8 and 42.9 ms−1, and in lower peak ground reaction forces and loading rates. Common characteristics were observed within the optimal initial body position with more extended front knees, as well as more flexion of the front and bowling arm shoulders than in current performances. Delays to the onset of trunk flexion, front arm and bowling arm shoulder extension, and wrist flexion were also common in the subsequent movement during the front foot contact phase. Lower front hip extensor and front shoulder flexor torques, as well as greater bowling shoulder extensor torques were also evident. This is useful knowledge for coach development, talent identification, and coaching practice.

Lumbar spine bone mineral adaptation: cricket fast bowlers versus controls

Elite adult male fast bowlers have high lumbar spine bone mineral, particularly on the contralateral side to their bowling arm. It is thought that bone possesses its greatest ability to...

Bone health and asymmetry in elite female cricketers

ABSTRACT The aim of this study is to determine if bone mineral density (BMD) and bone asymmetry differs between female cricket fast bowlers, spin bowlers and batters. BMD was determined at the total body, lumbar spine, and proximal femurs in 12 fast bowlers, 13 batters and 11 spin bowlers from pre-season DXA scans. High Z-scores at the total body, lumbar spine, and proximal femur were observed in all cricketers (mean Z-scores: +1.4 to +3.3) compared with a general age matched reference population. Fast bowlers had significantly greater BMD on the contralateral side of the lumbar spine compared with the ipsilateral side (p = 0.001, 5.9–12.1%). No asymmetry was found between hips in all groups. All cricket positions demonstrated high BMD at all measured sites. The lumbar spine of fast bowlers is asymmetric, with significantly greater BMD on the contralateral side of the spine, particularly at L4, possibly in response to the asymmetric lumbar loading patterns observed in bowling. Highlights Elite female cricketers demonstrate high BMD at total body, lumbar spine and proximal femur sites, regardless of playing position compared with a general age and ethnic group matched reference population. Fast bowlers have greater BMD on the contralateral (opposite bowling arm) side of the lumbar spine compared with the ipsilateral side, while a symmetrical pattern was observed in spin bowlers and batters. No asymmetry in BMD or section modulus between hips was observed at any proximal femur site for any cricket position.

Lumbar Bone Mineral Adaptation: The Effect of Fast Bowling Technique in Adolescent Cricketers.

Localized bone mineral density (BMD) adaptation of the lumbar spine, particularly on the contralateral side to the bowling arm, has been observed in elite male cricket fast bowlers. No study has investigated this in adolescents, or the role of fast bowling technique on lumbar BMD adaptation. This study aims to investigate lumbar BMD adaptation in adolescent cricket fast bowlers, and its relationship with fast bowling technique. Thirty-nine adolescent fast bowlers underwent anteroposterior dual x-ray absorptiometry scan of their lumbar spine. Hip, lumbopelvic and thoracolumbar joint kinematics, and vertical ground reaction kinetics were determined using three-dimensional motion capture and force plates. Significant partial (covariate: fat-free mass) and bivariate correlations of the technique parameters with whole lumbar (L1-L4) BMD and BMD asymmetry (L3 and L4) were advanced as candidate variables for multiple stepwise linear regression. Adolescent fast bowlers demonstrated high lumbar Z-Scores (+1.0; 95% confidence interval [CI], 0.7-1.4) and significantly greater BMD on the contralateral side of L3 (9.0%; 95% CI, 5.8%-12.1%) and L4 (8.2%; 95% CI, 4.9%-11.5%). Maximum contralateral thoracolumbar rotation and maximum ipsilateral lumbopelvic rotation in the period between back foot contact and ball release (BR), as well as contralateral pelvic drop at front foot contact, were identified as predictors of L1 to L4 BMD, explaining 65% of the variation. Maximum ipsilateral lumbopelvic rotation between back foot contact and BR, as well as ipsilateral lumbopelvic rotation and contralateral thoracolumbar side flexion at BR, were predictors of lumbar asymmetry within L3 and L4. Thoracolumbar and lumbopelvic motion are implicated in the etiology of the unique lumbar bone adaptation observed in fast bowlers whereas vertical ground reaction force, independent of body mass, was not. This may further implicate the osteogenic potential of torsional rather than impact loading in exercise-induced adaptation.

Assessment of trunk lateral flexion range of movement using a novel method in first class cricket players.

Lateral flexion range of movement (LF ROM) is used to assess and monitor recovery of side strain injury in athletes. This study established a reliable and pragmatic measure of LF ROM and investigated the stability of the measure over time in athletes. 1) Cross-sectional reliability study and 2) Cohort longitudinal study. Elite cricket teams in COUNTRY-AAA and COUNTRY-BBB Participants: Cricket players Methods: 1) The intra- and inter-rater reliability of two methods of measuring LF ROM were assessed (distance to the floor or distance to fibular head). Ten healthy first-class cricket bowlers were tested by three experienced physiotherapists. Intra-class correlations (2,1) were calculated for absolute agreement for all 3 testers. 2) Professional cricket fast bowlers were recruited from COUNTRY-AAA and COUNTRY-BBB domestic and international competitions. Lateral flexion range of movement was measured monthly during the pre- and competitive season. A one-way repeated measures analysis of variance was performed to identify difference within the pre-season, within the competitive season, and between competitive seasons. Lateral flexion range of movement towards and away from the bowling arm. Both methods had good intra- and inter-test reliability (ICC>0.84). As LF ROM to the floor was easier for clinicians it was used for the longitudinal study. Lateral flexion range of movement did not significantly alter throughout the pre- and competitive season or between seasons (p>0.05). This new method of describing LF ROM demonstrates good intra- and inter-rater reliability and stability over time and can be used as an outcome measure in side-strain injury.

Upper Lumbar Bone Stress Injuries in Elite Cricketers.

Describe the proportion of upper lumbar bone stress injuries (LBSI; T12-L3) relative to all LBSI, and the clinical presentation and diagnosis of upper LBSI in elite cricketers. Case series. Professional domestic and international cricket teams over a 9-year period. Elite Australian cricketers. Symptomatic upper LBSI diagnosed based on clinical findings and medical imaging. Prevalence, injury history, and clinical management. Twenty-four pace bowlers (22 male and 2 female) sustained 39 cases of upper LBSI (T12:2, L1:3, L2:20, L3:14). Upper lumbar vertebrae were involved in 41% (95% CI 31-51) of all LBSI in this cohort. Twenty-seven (69%, 54-81) cases had an injury that occurred only on the side contralateral to the bowling arm. Ipsilateral injuries tended to occur secondary to a contralateral nonunited defect. In all 7 cases with known radiology follow-up that had a contralateral then ipsilateral LBSI, the contralateral injury did not achieve bony union before the onset of the ipsilateral LBSI. For stress fractures with imaging follow-up, those who achieved bony union took longer to return to bowling training [median 152 days (IQR 117-188)], compared to those who achieved partial or no union [median 68 days (IQR 46-115)]. Upper LBSI in elite cricketers occurs in approximately 2 out of 5 cases of LBSI. Clinicians should allow sufficient time for upper LBSI to resolve and unite (if a fracture) because cases that returned to bowling training earlier were less likely to achieve bony union, and those that failed to unite commonly went on to have a recurrent LBSI. Therapy/prognosis/diagnosis level 2b.

The Effect Of Age On The Lumbar Spine Of Cricket Fast Bowlers

Senior cricket fast bowlers (FB) have high lumbar spine bone mineral, particularly on the contralateral side to their bowling arm. It is thought that bone possesses its greatest ability to adapt to loading during adolescence but is unknown at what age asymmetry develops in FB and how adaptation develops with age. PURPOSE: To determine how lumbar bone mineral and geometrical properties differ according to age in FB. METHODS: With NHS and institutional ethics approval, 107 elite adolescent and senior male FB aged 14 to 35 years received a single AP lumbar spine DXA scan (GE Lunar iDXA, GE Healthcare, USA). Bone mineral density (BMD) and bone mineral content (BMC) were derived for each vertebra, along with average vertebral height and width, area and Z-score (Lunar enCore v17, GE Healthcare, USA). Custom regions of interest derived the bone mineral in the lateral third of the non-dominant (ND) and dominant (D) sides of the vertebral body (respective to bowling arm). FB were split into 14-15 (n=27), 16-17 (n=28), 18-19 (n=22), 20-24 (n=16), and 25+ (n=14) age groups. ANOVAs were used to compare the age group means for each variable, with FFM as covariate. RESULTS: Lumbar spine BMD, BMC, Z-score, area, width and height significantly differed between age groups at all vertebral levels (P<0.01), but differences in area and height were no longer significant with FFM included as a covariate (P≥0.38). Mean BMD (± SD) L1-L4 Z-scores increased progressively with age from +0.83 ± 1.24 at age 14-15 to +2.69 ± 1.17 at age 25+. BMD and BMC on the ND and D sides significantly differed with age (P≤0.04) and side (P<0.01), and by age on each side (P≤0.04) as highlighted at L3 in figure 1. CONCLUSIONS: Adaptation to fast bowling, in terms of whole vertebra and site-specific bone mineral, substantially increases with age particularly on the ND side.

Classification and legality analysis of bowling action in the game of cricket

One of the hot topics in modern era of cricket is to decide whether the bowling action of a bowler is legal or not. Because of the complex bio-mechanical movement of the bowling arm, it is not possible for the on-field umpire to declare a bowling action as legal or illegal. Inertial sensors are currently being used for activity recognition in cricket for the coaching of bowlers and detecting the legality of their moves, since a well trained and legal bowling action is highly significant for the career of a cricket player. After extensive analysis and research, we present a system to detect the legality of the bowling action based on real time multidimensional physiological data obtained from the inertial sensors mounted on the bowlers arm. We propose a method to examine the movement of the bowling arm in the correct rotation order with a precise angle. The system evaluates the bowling action using various action profiles. The action profiles are used so as to simplify the complex bio-mechanical movement of the bowling arm along with minimizing the size of the data provided to the classifier. The events of interest are identified and tagged. Algorithms such as support vector machines, k-nearest neighbor, Naive Bayes, random forest, and artificial neural network are trained over statistical features extracted from the tagged data. To accomplish the reliability of outcome measures, the technical error of measurement was adopted. The proposed method achieves very high accuracy in the correct classification of bowling action.

Consistency of kinematic and kinetic patterns during a prolonged spell of cricket fast bowling: an exploratory laboratory study

ABSTRACTDue to the high incidence of lumbar spine injury in fast bowlers, international cricket organisations advocate limits on workload for bowlers under 19 years of age in training/matches. The purpose of this study was to determine whether significant changes in either fast bowling technique or movement variability could be detected throughout a 10-over bowling spell that exceeded the recommended limit. Twenty-five junior male fast bowlers bowled at competition pace while three-dimensional kinematic and kinetic data were collected for the leading leg, trunk and bowling arm. Separate analyses for the mean and within-participant standard deviation of each variable were performed using repeated measures factorial analyses of variance and computation of effect sizes. No substantial changes were observed in mean values or variability of any kinematic, kinetic or performance variables, which instead revealed a high degree of consistency in kinematic and kinetic patterns. Therefore, the suggestion that exceeding the workload limit per spell causes technique- and loading-related changes associated with lumbar injury risk is not valid and cannot be used to justify the restriction of bowling workload. For injury prevention, the focus instead should be on the long-term effect of repeated spells and on the fast bowling technique itself.

Kinetics Analysis of Pelvis, Thorax, and Bowling Arm in Cricket Bowling

ABSTRACT In this study, a three-dimensional (3D) dynamics model of the human body was developed to analyze the motion of fast bowling in cricket. Nine fast bowlers (22.4 ± 3.2 years) were selected from high-level regional cricket to bowl a series of balls at a target placed approximately on a ‘good length’ in line with the wickets, while their bowling actions were captured by a 10-camera 240 Hz motion analysis system (Motion Analysis Corp.). Motion analysis data were obtained from the tracked markers on the bowler strategically placed on the body to define a 3D joint coordinate system for each segment. Two Bertec force plates were used to measure the ground reaction forces. The resulting kinematic and force plate data of the fastest ball were fed into a computer model designed using the Mechanical Systems Pack (Wolfram Research, Inc., V. 5.2), a set of Mathematica packages written for the analysis of spatial rigid body mechanisms, implementing a dynamics formulation with Lagrangian multipliers. The computer model gave a 3D representation of the human body as a system of 15 rigid body segments with mass and inertia properties. Inverse solution dynamics were calculated to generalize certain fundamental aspects of the pelvis, thorax and bowling arm during fast bowling. How to cite this article Ferdinands R. Kinetics Analysis of Pelvis, Thorax, and Bowling Arm in Cricket Bowling. J Postgrad Med Edu Res 2015;49(4):159-163.

Extrinsic and intrinsic factors associated with non-contact injury in adult pace bowlers: a systematic review protocol.

Review question/objective Review question: which extrinsic and intrinsic factors are associated with non-contact injury in adult cricket pace bowlers? Review objective: the objective of this review is to determine the extrinsic and intrinsic factors associated with non-contact injury in adult pace bowlers. Inclusion criteria Types of participants This review will consider studies that include male cricket pace bowlers over the age of 18 years from all levels of play. Types of intervention(s)/phenomena of interest This review will consider studies evaluating the association between extrinsic and intrinsic factors, and lower quarter injury in pace bowlers. Intrinsic factors may include, but will not be limited to, muscle strength, flexibility, balance and biomechanics, while extrinsic factors may include bowling, but will not be limited to, workload, player position and time of play. Types of outcomes This review will consider studies that include any of the following outcome measures: non-contact injury. A non-contact injury is defined as an injury which is significant enough to cause an inability to fully or partially participate in training or matches and which was caused by an overuse mechanism rather than collision-type injuries.

Dynamics of Spin Bowling: The Normalized Precession of the Spin axis Analysed with a Smart Cricket Ball

As torque is imparted on a cricket ball before release, the spin vector precesses into the torque vector. Normalising the precession speed to the torque and the angular velocity yields the ‘normalised precession’, i.e. the angle between the spin vector and the torque vector. The maximal normalised precession was analysed in spin bowling, specifically in finger- and wrist spin, and topspin, sidespin and backspin deliveries. The data were recorded with a smart cricket ball and a Cortex motion analysis system. The maximal normalised precession at the beginning of the finger torque increased from topspin to backspin. The reason for this behaviour is that the motion of the bowling arm imparts a topspin on the ball, and therefore the spin axis does not have to change its direction if the fingers impart further topspin on the ball.

The Athletic Profile of Fast Bowling in Cricket

Cricket is a global sport played in over 100 countries with elite performers attracting multimillion dollar contracts. Therefore, performers maintaining optimum physical fitness and remaining injury free is important. Fast bowlers have a vital position in a cricket team, and there is an increasing body of scientific literature that has reviewed this role over the past decade. Previous research on fast bowlers has tended to focus on biomechanical analysis and injury prevention in performers. However, this review aims to critically analyze the emerging contribution of physiological-based literature linked to fast bowling in cricket, highlight the current evidence related to simulated and competitive in-match performance, and relate this practically to the conditioning coach. Furthermore, the review considers limitations with past research and possible avenues for future investigation. It is clear with the advent of new applied mobile monitoring technology that there is scope for more ecologically valid and longitudinal exploration capturing in-match data, providing quantification of physiological workloads, and analysis of the physical demands across the differing formats of the game. Currently, strength and conditioning specialists do not have a critical academic resource with which to shape professional practice, and this review aims to provide a starting point for evidence in the specific area.

Surface electromyographic analysis of the biceps brachii muscle of cricket bowlers during bowling

Cricket bowling generates forces with torques on the upper limb muscles and makes the biceps brachii (BB) muscle vulnerable to overuse injury. The aim of this study was to investigate whether there are differences in the amplitude of the EMG signal of the BB muscle during fast and spin delivery, during the seven phases of both types of bowling and the kinesiological interpretation of the bowling arm for muscle contraction mechanisms during bowling. A group of 16 male amateur bowlers participated in this study, among them 8 fast bowlers (FB) and 8 spin bowlers (SB). The root mean square (EMGRMS), the average sEMG (EMGAVG), the maximum peak amplitude (EMGpeak), and the variability of the signal were calculated using the coefficient of variance (EMGCV) from the BB muscle of each bowler (FB and SB) during each bowling phase. The results demonstrate that, (i) the BB muscle is more active during FB than during SB, (ii) the point of ball release and follow-through generated higher signals than the other five movements during both bowling categories, (iii) the BB muscle variability is higher during SB compared with FB, (iv) four statistically significant differences (p<0.05) found between the bowling phases in fast bowling and three in spin bowling, and (v) several arm mechanics occurred for muscle contraction. There are possible clinical significances from the outcomes; like, recurring dynamic contractions on BB muscle can facilitate to clarify the maximum occurrence of shoulder pain as well as biceps tendonitis those are medically observed in professional cricket bowlers, and treatment methods with specific injury prevention programmes should focus on the different bowling phases with the maximum muscle effect. Finally, these considerations will be of particular importance in assessing different physical therapy on bowler's muscle which can improve the ball delivery performance and stability of cricket bowlers.

Quantifying Elbow Extension and Elbow Hyperextension in Cricket Bowling: A case study of Jenny Gunn

In this study a method for determining elbow extension and elbow abduction for a cricket bowling delivery was developed and assessed for Jenny Gunn who has hypermobility in both elbows and whose bowling action has been repeatedly queried by umpires. Bowling is a dynamic activity which is assessed visually in real time in a cricket match by an umpire. When the legality of a bowler's action is questioned by an umpire a quantitative analysis is undertaken using a marker based motion analysis system. This method of quantifying elbow extension should agree with a visual assessment of when the arm is “straight” and should minimise the effects of marker movement. A set of six markers on the bowling arm were used to calculate elbow angles. Differences of up to 1° for elbow extension and up to 2° for elbow abduction were found when angles calculated from the marker set for static straight arm trials were compared with measurements taken by a chartered sports physiotherapist. In addition comparison of elbow extension angles at ball release calculated from the markers during bowling trials with those measured from high speed video also showed good agreement with mean differences of 0°±2°.

Analysis of segmental kinetic energy in cricket bowling

Fast bowling in cricket is an athletic motion requiring the coordination of multiple body segments in order to release a ball at high speed. The application of the kinetic link principle to bowling proposes that the optimal coordination of movement actuation follows a proximal to distal sequence, allowing the systematic and progressive transfer of angular momentum from the larger, heavier body segments to the smaller distal segments. An analysis of segmental kinetic energy potentially provides information on the order of segmental sequencing and the effectiveness of energy transfer between the segments throughout the kinetic link chain. However, there has been no calculation of segmental kinetic energy in cricket fast bowling. In this study, 34 fast bowlers (22.2±3.9 years) of premier grade level and above were tested using a three-dimensional motion analysis system (240Hz). Based on the range of measured balls (27.0 m s-1 to 35.6 m s-1), the sample was divided into four speed group categories: slow-medium, medium, medium-fast and fast. With exception of the fast group relative to medium-fast group, each faster group tended to have higher segmental kinetic energies. Although there were no clearly discernible sequencing differences between bowling speed groups, the temporal occurrences of peak segment kinetic energies showed that bowlers exhibited a general order of proximal to distal sequencing with the larger heavier proximal segments having the highest energy and activated first. In general, there is an approximate proximal to distal sequence in cricket bowling, which indicates that bowlers of varying speed levels first produce high kinetic energies in their trunk segments before circumducting the bowling arm during the acceleration phase.

The Shoulder Distraction Force in Cricket Fast Bowling

This preliminary study aimed to quantify the magnitude of the peak shoulder distraction force during the bowling action of female cricket fast bowlers. An eight camera Vicon motion analysis system operating at 120 Hz recorded the fast bowling actions of 18 Australian female fast bowlers. A three segment inverse solution model of the bowling arm was used to calculate the shoulder distraction force. A large peak shoulder distraction force was recorded during the early stages of the follow-through of the bowling action. When normalized for body weight, the distraction force was within the range of values reported for baseball and softball pitchers, who are considered to be at high risk of shoulder injury. Therefore, the relative importance of the peak shoulder distraction force in the fast bowling action for the development of shoulder pain in female cricket fast bowlers warrants further investigation.

Poster Session II, July 14th 2010 — Abstracts: Virtual & inertial sensors to detect illegal cricket bowling

Cricket bowlers suspected of an illegal arm action under the laws of cricket undergo testing in an approved biomechanics laboratory. They are assessed using a variety of analysis systems such as retro-reflective motion analysis systems (e.g. VICON). In general these systems allow for detailed and sophisticated analysis of human movement but are limited to the contrived laboratory environment and have suspect ecological validity. In-situ studies into bowling actions have typically relied upon frame by frame high speed match video analysis which, aside from the time involved, also has limitations in discriminating between sources of elbow movement such as flexion, extension, hyperextension, abduction & adduction. In-situ Micro Electro Mechanical Systems (MEMS) inertial sensors have the potential to discriminate between legal & illegal bowling actions in real time.Methodology and Results: Using previously developed wearable technology it is possible to measure arm action at a number of points on the bowling arm. The technology is based on inertial sensors and measures the arms changes in motion hundreds of times a second. These sensors respond to minute changes in inertia in linear and radial directions. These are known as accelerometers and rate gyroscopes, respectively. Case study results from a sub elite bowler show clear differences between throwing and bowling action. Processing of existing elite bowler laboratory motion capture data, to convert the 3D global frame of reference data into arm mounted ‘virtual’ inertial sensors has provided confirmation of information collected from sub-elite bowlers. These virtual sensors also provide information on the range of rotation rates and accelerations that occur during the bowling arm-action as well as identifying signatures that frame the bowling action.Conclusions: The sensors have been shown to be able to detect a number of arm actions. The virtual sensors have confirmed that these signals exist in the actions of elite bowlers. The virtual sensors have also identified signals that frame the bowling action allowing it to be identified in real time. The next step in this research is the development of sensors that can respond to the range of high rotation rates and accelerations, the laboratory verification of these sensors, and the testing of the sensors in competition.

Strength Assessment In Bowling And Non-bowling Arms Of Collegiate Ten Pin Bowlers

Bryce M. Winklepleck, Ashley R. Fryman, Jeremy A. Patterson, Wichita State University, Wichita, KS Isokinetic strength testing among athletes has been extensively researched, however little research has discussed the effects of strength among ten pin bowlers. During the sport of bowling, the bowling arm is subjected to numerous repetitions while forcefully launching a weighted bowling ball, which suggest greater muscle adaptations in the bowling arm compared to non-bowling arm. PURPOSE: To assess muscular strength and endurance of the bowling and non-bowling arm of collegiate ten pin bowlers. METHODS: Twenty-five (13 male; 12 female) college bowlers were tested for bilateral upper body strength and endurance with an isokinetic dynamometer (Biodex, System 4). Subjects were seated and positioned vertically to allow full extension and flexion of the elbow to assess strength (60°·s-1) and endurance (240°·s-1) simulating a chest-press exercise. RESULTS: All subjects but one bowled with their dominant arm. Subjects (N=25) produced significantly (P<0.05) greater strength and endurance outcomes during elbow extension in the bowling arm compared to the non-bowling arm (115.6±43.5 vs. 98±32.8 N·m·kg-1; and 66.5±26.8 vs. 59.4±24.1 N·m·kg-1, respectively). Greater strength (60°·s-1) was also produced during elbow flexion in the bowling arm (139.1±51.2 N·m·kg-1) compared to the non-bowling arm (131.1±49.4 N·m·kg-1). Muscular endurance was significantly greater in the bowling arm during elbow extension (push) and no significant (P>0.05) differences observed in elbow flexion (pull). However, when separating the group by gender, the female bowlers (N=12) produced significantly (P<0.05) greater torque in both elbow extension movements at 60°·s-1 and 240°·s-1 (109±45.3 vs. 91±33.3 N·m·kg-1; and 61.4±25.2 vs. 55.2±25.1 N·m·kg-1) in the bowling arm compared to the non-bowling arm. CONCLUSION: College bowlers perform hundreds of repetitions with their bowling arm with a weighted object (13-16lbs), thus allowing for muscle adaptations and development of upper body muscular strength and endurance over the non-bowling arm.

Wearable sensors for the monitoring of bowling action in cricket

Introduction: In the laboratory environment biomechanical characteristics of cricket fast bowlers are assessed using a variety of analysis systems such as retro-reflective motion analysis systems (e.g. VICON). In general these systems allow for detailed and sophisticated analysis of human movement but are limited to the contrived laboratory environment. Previous studies into bowling actions have typically relied upon frame by frame high speed match video analysis or 3 dimensional motion analysis obtained in a laboratory setting. It is generally considered that laboratory analyses provide a more detailed and accurate analysis of bowling actions including but do not provide a real world analysis environment. Methodology and Results: Using previously developed wearable technology it is possible to measure arm action at a number of points on the bowling arm. The technology is based on inertial sensors and measures the arms changes in motion hundreds of times a second. These sensors respond to minute changes in inertia in linear and radial directions. These are known as accelerometers and rate gyroscopes, respectively. When combined with absolute positioning technologies such as magnetometers and even GPS (Global Positioning System), laboratory equivalent performance analysis can be obtained.. By comparing the movement of different limb segments it is possible to devolve a detailed picture of arm action.. Case study results from a sub elite bowler show clear differences between throwing and bowling action with elbow abduction and extension being clearly evident signatures in the data Conclusions: The sensors have been shown to be able to classify arm action with comparable accuracy to existing lab based methods. It is hoped that with more complete validation this technology can be used as a training tool to aid in the correction of bowling action to prevent injury, improve performance and correct suspect action.