A simple and inexpensive photographic method has been developed whereby many kinematic components of the walking act in the sagittal, frontal, and transverse planes can be measured and related temporally. A factorial design was used to study the displacement patterns of sixty normal men who ranged in age from twenty to sixty-five years and in height from sixty-one to seventy-four inches. Each subject's weight was within normal limits for his height and frame size.

There was striking similarity in the duration of successive phases of stance, swing, and double-limb support during the same walking trial and during repeated trials of the same subject. Step and stride length and stride width showed the same striking similarity. Foot angles, however, showed greater individual variability.

The differences in timing and stride dimensions did not relate systematically with age. However, the subjects sixty to sixty-five years old differed from younger subjects in that they took shorter steps and strides and showed a greater degree of out-toeing.

The only variables which related systematically with height were the step and stride lengths, with the tall subjects taking the longest steps and strides and the short subjects, the shortest.

Seven displacement patterns of free-cadence walking were analyzed for sixty normal men from twenty to sixty-five years old and from sixty-one to seventy-four inches tall. These displacement patterns include sagittal rotation of the pelvis, hip, knee, and ankle and vertical, lateral, and forward movement of the trunk.

Each movement pattern was strikingly similar for repeated trials of the same subject and for subjects in the various age and height groups. Slight differences in the magnitude of hip flexion excursion occurred, which showed a low positive correlation with age and a similarly low but negative correlation with height.

There was no evidence of presenile changes in these excursions among our oldest subjects, except for some decrease in the magnitude of ankle extension at the end of the stance phase.

The serial transverse rotations of the pelvis and thorax have been analyzed in free-cadence walking of sixty normal men. Although there was striking similarity in these excursions for repeated trials of the same subject, there was wide variation in these excursions among the subjects in similar age and height categories. These variations suggest that pelvic and thoracic rotation are not obligatory elements of normal gait. The decreased pelvic rotation in the group sixty to sixty-five years old may possibly represent another aspect of the presenile pattern of walking.