Practical Applications: Reliability of the Tuck Jump Test and Hop Testing in an Elite Netball Population Rosalyn C. Cooke and Dr Lee C. Herrington Physiotherapy Bath and Manchester Background Netball is a sport predominantly played by females requiring movement patterns involving cutting, landing and deceleration with one step and is a sport where ACL and knee injuries are common. Injury prevention is a key priority and the use of functional performance tests may have a role with this due to their low cost, easy implementation and high biomechanical sensitivity. The tuck jump and cross over hop require the subject to repeatedly produce and absorb force in multiple planes neuromuscular deficits may be demonstrated and therefore identify potential for injury risk. Performance question: The purpose of this study was to review the reliability of two functional performance tests identified within the literature to have potential predictive value of impaired neuromuscular performance that may contribute to injury. Figure 1:Tuck Jump Testing Methods: Twenty seven female athletes from the elite England Netball program (Mean Age 22.6 +/- 3.5years, Height 179.6cm +/-6.57 Body Mass 75.3kg +/- 6.90) completed the Hop Test Battery described by Noyes et al (1991) and one repetition of the Tuck Jump test (Figure 1) in a single testing session. Data regarding precious injury history and leg dominance was also recorded to enable limb symmetry index (LSI) to be calculated and identification of ACL reconstructed subjects (ACLR). LSI is expressed as the percentage value of one limb versus the other and can be based on different variables such as dominant versus non-dominant, or involved (pathology) versus uninvolved. Statistical analysis was completed to assess reliability of the two tests using SPSS. Results showed intraclass correlation coefficients to demonstrate very good reliability (ICC > 0.99) for x-over hop test and kappa values for the tuck jump test showed a fair to very good strength of agreement (K=0.2232-0.9063). Results: The mean scores for the cross over hop tests are higher than previously reported, with the ACLR group producing greater mean scores for the cross over hop test (ACLR =5.37m Normal = 5.22m) than the normal population and a mean LSI of 102.86% versus 100.62% in the normal. This may be a reflection of the study population who regularly undertake hopping and landing activities and are a mean of 6.1 years (range 2-11years) post ACL reconstruction having successfully returned to elite level sport. Normal LSI is reported within the literature to be between 85-90%. This study found mean LSI to range from 97-103% across all tests in both groups. This may indicate that successful rehabilitation following ACLR requires a LSI above normal function i.e. greater than 90%. Normative values for tuck jump scores in an elite sporting population are not published making population comparison or intervention evaluation difficult. The tuck jump assessment offers a repeated effort measure of neuromuscular performance that may demonstrate risk factors for injury not seen in hop tests. In the results of this study the ACLR group produced higher LSI for the cross over hop than normal group but exhibited greater deficit on the tuck jump test. The use of an observed criteria based bilateral task does not produce an exact score of asymmetry but does provide a measure for deficits in an individual’s ability to repeatedly produce sound landing mechanics. This is critical in sports that require multiple changes of direction both horizontal and vertical in a high risk population. Practical Applications: The use of a battery of tests that require unilateral and bilateral tasks provides a comprehensive assessment of neuromuscular function and potential for injury risk. Screening within the England Netball now consists of a combination of hop and tuck jump tests which are completed with all age groups within the program. This is enabling high risk athletes to be tracked as they progress through the performance program. This information has also directed and underpinned our prehabilitation interventions. Further research is in progress to assess the impact of prehabilitation training in this population on these functional performance measures  References Myer, G.D., Ford, K.R., Brent, J.L. & Hewett, T.E. JSCR26(8):2265-2271,2012; Myer, G.D., et al JOSPT. 41 (6):377-387,2011 Munro, A. & Herrington, L. JSCR25(5):1470-1477,2011 Noyes et al Am J Sports Med 19:513-518,1991. Otago, L. Journal of Science and Medicine in Sport 7,(1) 85-95. 2004