Consistency of leg extension power assessments in older men: The osteoporotic fractures in men (MrOS) study

This study examined the consistency of the Nottingham power rig in assessing leg extension power in older men, assessed between different examiners with adjustment for the order of measurement (time) and clinic. Fifty-five men (mean, 73 yrs) enrolled in the Osteoporotic Fractures in Men Study had maximum leg extension power of each leg measured at baseline and remeasured 1 wk later. There was a significant effect of time (P < 0.01). The second visit had an average increase in leg extension power (right leg, 14.2 W; left leg, 16.5 W). After accounting for the effect of time, a low coefficient of variation was observed between examiners (right leg 3.49%; left leg 3.46%). Data from the two time points corresponded reasonably well. The effect of time and fatigue should be considered when performing this measurement. The Nottingham power rig provided a reproducible measure of leg extension power in this multisite study of older men.