Reproducibility of the Senior Fitness test and handgrip strength in older adults

Abstract Reproducibility is defined as the ability to achieve similar results (agreement) when a study or test is repeated using the same protocol and under similar conditions. It is a critical aspect of research and clinical practice. The aim of this study was to evaluate the reproducibility of the Senior Fitness Test and handgrip strength assessments in older adults. The sample consisted of 72 untrained older adults (16 men and 56 women). All tests and retests were conducted by experienced and trained evaluators. The tests were performed in the following order: chair stand test (CST), biceps curl, sit and reach, timed up and go (TUG), back scratch, handgrip strength, and the six-minute walk test (6MWT), in accordance with the Senior Fitness Test protocol. An adjustable handgrip dynamometer was used to assess handgrip strength. The test chair sit and reach, TUG, handgrip strength, and back scratch demonstrated an intraclass correlation coefficient (ICC) classified as excellent (>0.9). The CST, 6MWT, and biceps curl tests showed ICCs classified as good, moderate, and low, respectively (0.76, 0.72, 0.51). In conclusion, the reproducibility of handgrip strength, sit-and-reach, back scratch, and TUG were classified as excellent. On the other hand, the CST, biceps curl, and 6MWT had ICCs below 0.77, indicating the need for retesting.