  The worldwide population is aging and countries are facing ongoing challenges
in improving the safety of elderly pedestrians. In this work, single-file
movement of the elderly are experimentally compared with that of different age
groups. The findings indicates that the age is not the only factor influencing
the pedestrian dynamics but the heterogeneity of the crowd composition and the
familiarity among neighboring pedestrians also have significant effects. The
existence of three regimes in the relationship between headway and speed is
confirmed. In the strong constrained regime, the slope of the relationship
between headway and speed of the elderly is bigger than that of the young,
which means that the elders are more sensitive to the spatial headway than the
young when adapting the speeds. However, the difference of the slopes in the
weakly constrained regime is small, which indicates a weak dependency between
age and the adaption time. The elderly need longer headway during the
transformation of the motion state. Besides, the 'active cease' behavior of
pedestrians, which is explained with the least effort principle, is observed in
the experiment. The findings offer empirical data of the elderly under high
densities and can be useful for the improvement of the pedestrian modelling and
the construction of elderly friendly facilities.
