In general, elderly people tend to raise their feet higher than necessary when stepping over steps to reduce the risk of tripping and falling. A research group at Tokyo Metropolitan University has revealed that this behavior can reduce the flexibility of movement.
It is known that falls occur most often in elderly people when they step over steps while walking. Therefore, some elderly people take the conservative strategy of elevating their feet to avoid collisions with steps. However, by elevating their feet, they can avoid both large and small steps, leaving elderly people who adopt this strategy with no opportunity to adjust their movements in daily life.
In this study, we investigated the relationship between opportunities to adjust movements and movement flexibility (the ability to flexibly change movements depending on the situation), using 21 healthy young adults and 65 An experiment was conducted in which 26 healthy elderly people over the age of XNUMX were asked to repeatedly step over steps. At this time, we applied an analysis method called Uncontrolled Manifold (UCM) analysis to quantify the flexibility of the movement across steps as "interlocking between joints."
The results showed that elderly people had lower inter-joint coordination when stepping over steps compared to younger people. Furthermore, regardless of age, a significant negative correlation was found between the height of the foot when stepping over a step and the coordination between joints. In other words, it has become clear that people who tend to raise their feet higher when stepping over a step have less flexibility when stepping over a step.
The results of this study suggested that raising one's feet high at any time for safety reasons when stepping over a step may reduce the flexibility of movement and actually hinder the ability to maintain balance and avoid obstacles. Repeating the same movements on a daily basis may reduce the flexibility to respond to unexpected changes. This knowledge is expected to lead to the development of rehabilitation methods to overcome decreased flexibility.
