Angular tests for estimating hamstring flexibility

Description of their measurement method and reference values

Abstract

 

The assessment tests based on angular measurements are widely used to estimate and monitor hamstring muscle flexibility in both clinic and scientific settings. Several angular assessment tests have been described in the scientific literature, among which stand out: a) the straight leg raise test; b) the knee extension test; and c) the assessment tests that study the hip position and the caudal portion of lumbar spine at maximal trunk flexion position, distinguishing between "vertical hip joint angle" and "horizontal hip joint angle". Several limitations have been reported regarding the precision of these tests to estimate hamstring flexibility, such as: the influence of pelvis and spine movements, the position of the ankle joint (neutral position vs. dorsi-flexion), the use of different cut off values, the magnitude of the strength and speed used to carry on the tests, the warm-up design and the variability of the measurement tools used. This variability in the assessment methodologies might affect the final decision of choosing one or another assessment test by scientists, clinicians, and sport practitioners. Therefore, the main purposes of the current literature review are: to describe the assessments methodology of the most common angular tests used in clinic and scientific settings, as well as to report the cut-off values, which could be used for practitioners in order to categorize the hamstring flexibility as normal or limited.