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The aim of this study was to characterize relationships between anthropometric and isoinertial strength characteristics and bowling speed in junior and senior cricket fast bowlers. Subjects were first-class senior (n = 24; mean [+ or -] SD age = 23.9 [+ or -] 4.8 years, height = 187.4 [+ or -] 4.8 cm, mass = 87.8 [+ or -] 8.4 kg) and junior representative (n = 48; mean [+ or -] SD age = 14.8 [+ or -] 1.3 years, height = 175.7 [+ or -] 9.8 cm, mass = 65.8 [+ or -] 12.9 kg) male fast bowlers. A full anthropometric profile, upper- and lower-body isoinertial strength tests, and peak bowling speed (Vpeak) were assessed on the same day. The senior bowlers had a substantially faster Vpeak (126.7 km*[h.sup.-1]) than the juniors (99.6 km*[h.sup.-1]), a larger estimated muscle mass (seniors 40.0 [+ or -] 3.9 kg, juniors 28.3 [+ or -] 5.6 kg), and a greater bench press throw and deltoid throw (all p < 0.01). The best multiple predictors of Vpeak for the junior bowlers were the static jump, bench throw, body mass, percentage muscle mass, and height (multiple-correlation r = 0.86). For the senior bowlers, static jump and arm length correlated positively with Vpeak (multiple-correlation r = 0.74). The 1-legged countermovement jump was negatively correlated with Vpeak in both groups. We conclude that differences in Vpeak between junior and senior bowlers relate primarily to body mass and upper-body strength. However, lower body strength is a more important contributor to Vpeak in senior bowlers. Key Words. cricket, performance, isoinertial strength, anthropometry, ball-release speed, age

Inertial measurement units (IMUs) provide a practical solution for attaining key performance data for wheelchair sports. The effects of IMU placement position on the identification of propulsion characteristics are unknown. The aim of this study was to determine the variability in the reliability of cycle time measurements (time between hand contacts) across IMU locations on the chair frame (axle housings), and wheels (axle, push rim, outer rim), on both the left and right sides (n = 8). Contacts were defined by spikes in the resultant acceleration data, corresponding to impact between the hands and push rim, and verified against motion capture. Five elite wheelchair racing athletes propelled at racing speeds on a treadmill. Excellent inter-rater Intraclass Correlation Coefficient values indicated high reliability and repeatability for both motion capture and IMU signal analysis approaches (R = 0.997, p < 0.001 and R = 0.990, p < 0.001, respectively). The best results were (as determined by the best between method agreement) were observed for IMUs located on the frame. Detection reliability was positively associated with signal-to-noise ratio of the acceleration data. The IMU assessment approach facilitates an automated processing capability, which is an improvement to the currently used video analysis. [ABSTRACT FROM AUTHOR]

The measurement of lumbar spine motion is an important step for injury prevention research during complex and high impact activities, such as cricket fast bowling or javelin throwing. This study examined the performance of two designs of a lumbar rig, previously used in gait research, during a controlled high impact bench jump task. An 8-camera retro-reflective motion analysis system was used to track the lumbar rig. Eleven athletes completed the task wearing the two different lumbar rig designs. Flexion extension data were analyzed using a fast Fourier transformation to assess the signal power of these data during the impact phase of the jump. The lumbar rig featuring an increased and pliable base of support recorded moderately less signal power through the 0-60 Hz spectrum, with statistically less magnitudes at the 0-5 Hz (p = .039), 5-10 Hz (p = .005) and 10-20 Hz (p = .006) frequency bins. A lumbar rig of this design would seem likely to provide less noisy lumbar motion data during high impact tasks. [ABSTRACT FROM AUTHOR]

Purpose: The time-motion characteristics and the within-athlete variability in movement patterns were quantified for the same male fast bowler playing One Day Inter- national (ODI) cricket matches (n = 12). Methods: A number of different time motion characteristics were monitored using a portable 5-Hz global positioning system (GPS) unit (Catapult, Melbourne, Australia). Results: The bowler's mean workload per ODI was 8 ± 2 overs (mean ± SD). He covered a total distance of 15.9 ± 2.5 km per game; 12 ± 3% or 1.9 ± 0.2 km was striding (0.8 ± 0.2 km) or sprinting (1.1 ± 0.2 km), whereas 10.9 ± 2. 1 km was spent walking. One high-intensity (running, striding, or sprinting) repetition (HIR) occurred every 68 ± 12 s, and the average duration of a HI effort was 2.7 ± 0.1 s. The player also completed 66 ± 11 sprints per game; mean sprint distance was 18 ± 3 m and maximum sprinting speed 8.3 ± 0.9 m·s-1. Conclusions: The movement patterns of this fast bowler were a combination of highly intermittent activities of variable intensity on the base of ∼ 16 km per game. This information provides insight for conditioning coaches to determine the physical demands and to adapt the training and recovery processes of ODI fast bowlers. [ABSTRACT FROM AUTHOR]

CRICKET HAS TRADITIONALLY FOLLOWED THE GENERAL STRENGTH AND CONDITIONING PRACTICES OF OTHER SPORTS. AS THE PHYSICAL DEMANDS OF CRICKET HAVE BEEN INVESTIGATED MORE FULLY, IT IS APPARENT THAT THE SPORT PRESENTS WITH UNIQUE PHYSICAL REQUIREMENTS AND CHALLENGES. TO ASSIST PRACTITIONERS TO IMPLEMENT FAST BOWLER PHYSICAL PREPARATION BEST PRACTICE IN CRICKET, WE PROVIDED THE READER WITH BIOMECHANICAL, INJURY SURVEILLANCE DATA, AND PREDICTORS OF INJURY INFORMATION IN PART 1 OF THIS SERIES. PART 2 FOCUSES ON MECHANICAL AND ANTHROPOMETRIC FACTORS RELATING TO FAST BOWLING. THE REVIEW CONCLUDES WITH RECOMMENDATIONS FOR THE PHYSICAL PREPARATION OF CRICKET FAST BOWLERS. [ABSTRACT FROM AUTHOR]

This study investigated the bowling arm kinematics of 21 elite fast bowlers (mean ± SD; age = 27.8 ± 3.9 years) while performing in test, tour and one day international matches. Thirty-one of the 34 deliveries analysed exhibited straightening at the elbow joint (straightening min = 3°, max = 22°, mean ± SD = 9 ± 5°), which by strict definition in the 2000 laws of cricket made them illegal. Five deliveries from three bowlers exhibited hyperextension of the bowling elbow (19 ± 5°). When assessed against an arbitrary threshold of 15° for elbow straightening, ball speeds for deliveries above this threshold (39.5 ± 2.0 m/s) were significantly faster (effect size = 1.4; p = 0.006) than deliveries below it (37.1 ± 1.4 m/s). When grouped by delivery length, the bouncers and short deliveries recorded more elbow straightening (12 ± 6.6°) than the good length deliveries (9 ± 4.4°) and the full deliveries (8 ± 5.7°), although these were not statistically significant differences. The results of this study support the implementation of a tolerance threshold for assessing the legality of fast bowling actions. Further research is recommended into in-match kinematic modelling, laboratory based assessments of illegal bowling actions, perceptual aspects of bowling actions and remedial methods to reduce elbow straightening in bowling actions. [ABSTRACT FROM AUTHOR]

In this study we analysed technique, ball speed and trunk injury data collected at the Australian Institute of Sport (AIS) from 42 high performance male fast bowlers over a four year period. We found several notable technique inter-relationships, technique and ball speed relationships, and associations between technique and trunk injuries. A more front-on shoulder alignment at back foot contact was significantly related to increased shoulder counter-rotation (p < 0.001). Bowlers who released the ball at greater speeds had an extended front knee, or extended their front knee, during the front foot contact phase (p < 0.05). They also recorded higher braking and vertical impact forces during the front foot contact phase and developed those forces more rapidly (p ≤ 0.05), A maximum hip-shoulder separation angle occurring later in the delivery stride (p = 0.05) and a larger shoulder rotation to ball release (p = 0.05) were also characteristics of faster bowlers. Bowlers suffering lower back injuries exhibited typical characteristics of the 'mixed' technique. Specifically, the hip to shoulder separation angle at back foot contact was greater in bowlers who reported soft tissue injuries than in non trunk-injured bowlers (p = 0.03), and shoulder counter-rotation was significantly higher in bowlers who reported lumbar spine stress fractures than non trunk-injured bowlers (p = 0.01). The stress fracture group was also characterised by a larger hip angle at front foot contact and ball release, whereas a more flexed front knee at ball release characterised the non trunk-injured group. [ABSTRACT FROM AUTHOR]