Factor M as a correlate of physical fitness: imagination or just more energy

Determined whether 16PF scale scores could contribute significantly to the prediction of a measure of fitness. Sixty-three firemen from a large metropolitan area in the Southeast were Ss. Factor M contributed significantly to the prediction of one measure of fitness (i.e., treadmill time). The assumption cited in the literature that Factor M reflects "imagination" in individuals who score high on fitness measures was questioned. The article concluded that Cattell's earlier work relating high Factor M to high energy and endurance suggests a more logical interpretation of Factor M vis à vis measures of fitness.