Lift-and-Raise Hamstring Flexibility Test - Reliability and Validity
The purpose of the present investigation was to determine initial reliability and criterion-related validity of the Lift-and-Raise Hamstring Flexibility test. Although the Sit-and-Reach test is the most common measure of hamstring flexibility in physical fitness testing batteries, the Sit-and-Reach has been reported to have inherent limitations due to trunk and extremity length differences of individuals and only moderate validity (r=.64). Attempts to modify the Sit-and-Reach have claimed to limit the bias of proportional extremity differences, yet validity measures remained moderate (r=.66). The Lift-and-Raise hamstring flexibility test was developed to offset the limitations found within the Sit-and-Reach and modified Sit-and Reach tests. The Lift-and Raise instrument, similar to an enlarged goniometer, displays a range of 40 degrees to each side of 90 degrees. The instrument slides vertically along a slide stick attached to a wall, allowing adjustments to be made for femoral leg length. With the subject supine, the amount of active knee extension was measured while the hip was placed at 90 degrees of flexion. Knee extension was measured by lining a wooden dowel over the medial joint line of the knee and extending it from the posterior medial malleolus to the instrument markings. Fifty-three college-aged students from an elective basic instruction tennis class were administered three trials of the Lift-and-Raise test by two independent testers. Based on three attempts, the highest degree of active knee extension was recorded for each tester. High interrater reliability (r=.934) was found between the two testers. A second group of college-aged students (n=37) from an Introduction to Athletic Training class were administered the Lift-and-Raise test and a second criterion-related hamstring flexibility test. The criterion measure utilized the Cybex7 NormJ Testing and Rehabilitation System to determine the degree of knee extension using body positioning similar to a 90-to-90 hamstring flexibility assessment used in athletic training, physical therapy and orthopedic settings. Correlation coefficients between the Lift-and-Raise test and the Cybex7 testing protocol were high (r=.889). Findings indicated the Lift-and-Raise test to have high consistency between testers and demonstrated high criterion-related validity when used as an assessment of hamstring flexibility. Research is underway to determine testing reliability with physical educators and students.