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.