Factor analysis of seventeen joint flexibility measures

Abstract

Seventeen measures of joint flexibility were obtained on 190 volunteer subjects, 124 women and 66 men. Using a Leighton flexometer and a Universal goniometer seventeen measures of flexibility were taken. A principle axes method of factor analysis with oblique rotation revealed four significant factors. The first factor had 14 significant factor loadings (r>0.30) with Factor II having 13, Factor III, 11 and Factor IV, 16. Each factor included one very high coefficient; Factor I had trunk lateral flexion (0.96), Factor II, shoulder flexion‐extension (0.91), Factor III, trunk flexion‐extension and Factor IV, hip flexion (0.94). These variables also had high coefficients in the other three factors which were reflected by high communality values; trunk lateral flexion (h = 0.92), hip flexion (h = 0.88) trunk flexion‐extension (h = 0.88) and shoulder flexion‐extension (h = 0.83). Analysis of the data indicated four factors representing an underlying structure for body flexibility. Within the four factors, four variables contributed a high percentage of the variance, suggesting total body flexibility may be represented using these four measures.