The reliability of the lateral step test

Context: Functional strength measures correlate more closely with functional performance than non-functional strength measures.Objectives: To determine the reliability of the lateral step test as a measure of maximal strength. Design: Intertester repeated measures. Setting: Research laboratory. Participants: Twenty four healthy, pain free subjects. Intervention: Two protocols (A and B) were evaluated. The protocols were identical except protocol B involved a three second pause. Participants performed a one repetition maximum (1RM) for each protocol on two occasions separated by one week. Main Outcome Measures: Step height (nearest cm) representing 1RM. Results: Both protocols demonstrated excellent reliability, protocol A: ICC = 0.94 (95% CI, 0.87 to 0.97), SEM = 1.47 cm. Protocol B: ICC= 0.94 (95%CI, 0.85 to 0.97).Percent close agreement within 2 cm was 83.3% for protocol A and 79.1% for protocol B. Conclusion: Both protocols demonstrated excellent inter-tester reliability as measures of functional lower limb strength.