2009 Volume 24 Issue 5 Pages 693-696
[Purpose] In this study, we investigated the effect of the shape of the sensor pad used in a hand-held dynamometer with a fixed belt on the values of isometric knee extension strength. [Subjects] The subjects were 36 healthy adults: 18 males, 18 females; average age, 20.5 ± 1.7 years. [Method] The sensor pads were one in previous use (old pad) and a new one made for this study. The new pad was designed to be thicker, and have a smaller diameter of the curved surface than the old pad. Using the two types of pad we performed measurements of muscle strength on the same day, and compared the measurement values, pain at the time of measurement, and measurement reproducibility. [Results] Values for knee extension strength in the order of the new pad, old pad were 51.4 ± 14.7 and 47.3 ± 14.6 kgf on the first day, and 51.9 ± 15.3 and 47.9 ± 14.0 kgf on the second day, respectively, with the new pad showing a significantly higher value on both days. Pain at the pad contact surface showed a significantly lower value for the new pad. The intraclass correlations for the new and old pads on the first and second days were 0.91 and 0.94, respectively, both showing good intra-rater reproducibility. [Conclusion] The shape of the sensor pad had a substantial effect on the value of isometric knee extension strength and pain at the time of measurement. When measuring knee extension strength, a pad of suitable thickness and shape should be used.
