Background: Persons aged ≥ 65 years are currently the world's fastest growing age group. An important complication of age is the increasing risk of falls. Falls have multifactorial etiology and modifiable risk factors open for interventions in prevention and rehabilitation, are of high interest. In this context, strong hip abductors seem to be important to prevent falls. A newly adapted measurement device to measure hip abductor strength (HAS) in a closed chain position was developed. We aim to assess feasibility, intra- and inter-tester reliability and construct and criterion validity of the new measure.